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Made available in DSpace on 2015-03-19T16:20:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-12-01Bitstream added on 2015-03-19T16:29:20Z : No. of bitstreams: 1 S1679-62252014000400729.pdf: 1828279 bytes, checksum: 9942ce88b904e5112bb4e74b656744de (MD5) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Uma nova espécie de Hypostomus é descrita do rio Quente, drenagem do rio Paranaíba, bacia do alto rio Paraná no Brasil Central. O rio Quente é um riacho peculiar, raso e de correnteza, cujas temperaturas atingem em torno de 34ºC. A espécie nova é distinguida de todas as congêneres por ter as cinco séries de placas laterais com odontódeos hipertrofiados, os quais não são alinhados em fileiras, sendo mais conspícuos nos flancos do pedúnculo caudal nos indivíduos maiores. A espécie nova é conhecida apenas do rio Quente. A new species of Hypostomus is described from the rio Quente, rio Paranaíba drainage, in the upper rio Paraná basin in central Brazil. The rio Quente is a peculiar small and shallow fast water stream with water temperatures around 34ºC. The new species is distinguished from all congeners by having the five lateral series of plates with hypertrophied odontodes not aligned in rows and more conspicuous on flanks of caudal peduncle of the larger specimens. The new species is only known from the rio Quente. Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Biociências, Letras e Ciências Exatas Departamento de Zoologia e Botânica UEM, Universidade Estadual de Maringá Departamento de Biologia e Nupélia Núcleo de Pesquisas em Limnologia, Ictiologia e Aquicultura Universidade Estadual Paulista Júlio de Mesquita Filho Instituto de Biociências, Letras e Ciências Exatas Departamento de Zoologia e Botânica

The fish fauna of the Atrai River were studied for a period of two years from January 2011 to December 2012. Sampling was carried out by several fishing nets and traps on fortnight basis. A total of 74 fish species belonging to 27 families and 52 genera were recorded. Cyprinidae was the most dominant family contributing 18 species in 9 genera. Two alien species were found- Hypophthalmichthys molitrix and Hypostomus plecostomus. Thirty locally threatened species (Vulnerable 13.51%, Endangered 18.92% and Critically Endangered 8.11%) were recorded. But, no globally threatened species was found. Relative abundance of majority 36.49% species was rare. Global population trend of 24.32% recorded fish species was Declining. The highest number of species (42) was recorded in the November 2011. Whereas, the lowest the number of fish species (12) recorded in June and August 2011. Very high correlation was found between fish species and physical environmental parameters (air temperature, water temperature, and water transparency). This study concluded that Atrai River could be an excellent place for natural conservation of fish species. Nevertheless, efforts to maintain a sustainable fishing pressure, removal of existing alien species and avoiding further introduction of such species are recommended.

Aquarium trade is one of the most important pathways of biological invasion. Much attention has been given to target introduced species, but little is discussed on the associated bycatch ones. The aim of this paper is to analyze the risk of invasion by non-commercial invertebrates using aquarium stores as a model. Monthly visits to eight stores in Aracaju (Sergipe State) were performed from April to September 2011. Inspections were carried out and questionnaires were applied to owners and employees of the establishments. Two non-native species were identified, Melanoides tuberculatus (Gastropoda: Thiaridae) and Lernaea cyprinacea (Crustacea, Copepoda). Sixty-two specimens of M. tuberculatus were found among the aquatic plants in one of the stores, while L. cyprinacea was collected in four establishments parasitizing Carassius auratus, Hypostomus sp., Poecilia latipinna, Poecilia sphenops, Poecilia reticulata and Xiphophorus hellerii. The interviews that have been done with owners and employees revealed that none of the stores has submitted fishes and plants to quarantine, and the disposal of wastewater is directly into the sewer system. It is necessary to adopt preventive measures such as a quarantine period for fishes and the creation of a warning about the dangers of biological invasions or aquarium dumping for aquarium hobbyists to mitigate the risk of invasion.

Hypostomus dardanelos, new species Figs. 1-3 Hypostomus gr. cochliodon Fernandes et al., 2013: 843 [list of species and ecology]. Holotype. INPA 37342, 172.2 mm SL, Brazil, Mato Grosso State, munic��pio de Aripuan��, rio Madeira basin, rio Praia Grande (at its mouth to rio Aripuan�� downstream cachoeira Dardanelos and Andorinhas), 10��02���51���S 59��23���21���W, 8 Aug 2008, I. M. Fernandes. Paratypes. All from Brazil, Mato Grosso State, munic��pio de Aripuan��, rio Aripuan�� basin: MNRJ 36319, 1, 145.5 mm SL, rio Aripuan��, at rapids downstream cachoeira Dardanelos, 10��09���41.7���S 59��27���41.9���W, 12 Mar 2008, F. Pupo & I. Ver��ssimo. MNRJ 38652, 1, 119.8 mm SL, rio Aripuan��, left margin, 1500 m downstream Dardanelos waterfalls, 10��09���30���S 59��26���19���W, 11 Dec 2008, F. Pupo. MNRJ 38871, 1, 143.0 mm SL, rio Aripuan��, 500 m downstream Dardanelos waterfalls, 10��09���47���S 59��26���56���W, 28 Jul 2010, F. Pupo. MZUSP 37595, 2, 172.0-183.9 mm SL (larger specimen skeletonized after measuring), rio Aripuan��, Humboldt, 3 km downstream Cachoeira Grande falls, no coordinates available, 8 Nov 1976, Expedition MZUSP and INPA. MZUSP 37795, 1, 168.3 mm SL, rio Aripuan��, 8 Nov 1976, Expedition MZUSP and INPA. MZUSP 110798, 2, 135.5 - 163.7 mm SL, rio Aripuan��, 7 Jan 2004, F. A. Machado, C. M. C. Leite & F. Rosa. NUP 6758, 8, 118.8- 160.5 mm SL, collected with holotype. NUP 6759, 2, 115.5-141.2 mm SL, stream with unknown name, tributary to igarap�� Guaribal, 10��06���35���S 59��26���12���W, 8 Aug 2008, I. M. Fernandes. NUP 6760, 1, 143.5 mm SL, igarap�� Guaribal, tributary to rio Aripuan��, 10��06���35���S 59��26���12���W, 18-19 May 2008, I. M. Fernandes. NUP 6765, 1, 55.0 mm SL, stream with unknown name, tributary to rio Guaribal, 10��06���35���S 59��26���12���W, 18-19 May 2008, I. M. Fernandes. NUP 6775, 1, 151.8 mm SL, stream with unknown name, tributary to rio Praia Grande, 10��02���51���S 59��23���21���W, 19 May 2008, I. M. Fernandes. NUP 7098, 1, 46.0 mm SL, stream with unknown name, tributary to igarap�� Praia Grande, 10��02���45���S 59��27���24���W, 5 Aug 2008, I. M. Fernandes. NUP 7130, 2, 40.0-42.7 mm SL, stream with unknown name, tributary to igarap�� Praia Grande, 10��02���59���S 59��27���40���W, 5 Aug 2008, I. M. Fernandes. NUP 7192, 1, 42.0 mm SL, stream with unknown name, tributary to igarap�� Rio Claro, 10��03���09���S 59��33���20���W, 6 Aug 2008, I. M. Fernandes. NUP 7474, 4, 123.0-181.0 mm SL, collected with holotype. NUP 7637, 2, 12.3-40.1 mm SL, stream with unknown name, tributary to igarap�� Guaribal, 10��04���37���S 59��31���04���W, 15 May 2008, I. M. Fernandes. NUP 7694, 1, 42.0 mm SL, stream with unknown name, tributary to igarap�� Guaribal, 10��06���35���S 59��26���12���W, 5 Aug 2008, I. M. Fernandes. NUP 9452, 1, 40.6 mm SL, stream with unknown name, tributary to igarap�� Rio Praia Grande, 10��02���51���S 59��23���21���W, 17 May 2008, I. M. Fernandes. Non-type specimens. NUP 14655, 1, 103.7 mm SL, Igarap�� Arraia, tributary to rio Aripuan��, 10��07���15���S 59��31���42���W, 19 Jan 2013, H. P. Silva & C. H. Zawadzki. NUP 14656, 1, 66.8 mm SL, igarap�� Guaribal, tributary to rio Aripuan��, 10��08���51���S 59��29���56���W, 19 Jan 2013, C. H. Zawadzki & H. P. Silva. Diagnosis. Hypostomus dardanelos is distinguished from its congeners by its unique color pattern of yellowish-brown ground color covered by well-defined dark spots of relatively equal size, evenly spaced and moderately set along the dorsal region of the body and fins, except on the ventrolateral region of the caudal peduncle, and proximal region of anal and caudal fins, which are devoid of spots (vs. without spots, with pale spots, or with moderately- or sparsely-set dark spots that are usually larger, more faded, and more remotely spaced towards posterior region of body, and with ventrolateral caudal peduncle usually bearing spots). Additionally, H. dardanelos is further distinguished from all species of Hypostomus, except those belonging to the Hypostomus cochliodon group, by having few spoon-shaped teeth, 10 to 13 (vs. more than 16 villiform teeth), dentaries angled less than 80�� (vs. dentaries angled more than 80��) and by the presence of a notch between hyomandibular and the metapterygoid (vs. notch absent). The new species is further diagnosed from H. hemicochliodon Armbruster, H. kopeyaka Carvalho, Lima & Zawadzki, H. sculpodon Armbruster, H. soniae Hollanda Carvalho & Weber, and H. weberi Hollanda Carvalho, Lima & Zawadzki by possessing massive round teeth, with mesial cusp large and distinctly spoon shaped and outer cusp, if present, fused to the mesial one and scarcely noticeable (vs. clearly bicuspid teeth, although the lateral cusp is considerably smaller than mesial cusp); from H. hemicochliodon, H. kopeyaka, H. paucimaculatus Boeseman, H. sculpodon, H. waiampi Hollanda Carvalho & Weber, H. weberi by lacking a medial buccal papilla (vs. medial buccal papilla present); from H. ericae Hollanda Carvalho & Weber, H. plecostomoides, and H. pyrineusi (Miranda Ribeiro) by having strong keels in dorsal, mid-dorsal and median series of plates (vs. keels absent in H. pyrineusi and moderately-developed keels in H. ericae and H. plecostomoides); from H. ericius Armbruster by having caudal fin usually with dark spots distally (vs. caudal fin dark blurred distally); from H. hondae by having the exposed portion of opercle inconspicuous (vs. exposed portion of opercle easily visualized); from H. macushi Armbruster & Souza by having small dark spots (vs. medium to large dark spots); from H. oculeus (Fowler) by lacking strong keel on mid-ventral series of plates (vs. having strong keels on all lateral series plates, including the mid-ventral one, see Armbruster, 2003, fig. 16); from H. pagei by having uniformly conspicuous small dark spots (vs. spots becoming faded or absent); and from H. taphorni by having both caudal-fin lobes evenly colored (vs. bicolored caudal fin with lower lobe darker). Description. Meristic and morphometric data in Table 1. Holotype and additional specimens in Figs. 1-3. Dorsal profile slightly convex to straight from snout tip to interorbital area, strongly convex from interorbital area to dorsal-fin origin, and gently descending from dorsal-fin origin to first procurrent plate of caudal fin. Ventral profile almost straight from snout tip to caudal fin. Caudal peduncle slightly compressed laterally, ellipsoid in cross section. Body width at cleithral region greater than head depth. Head broad and deep, dorsally covered with dermal bones, except for small naked area on snout tip (snout tip plated in one specimen, NUP 7474, 181.0 mm SL). Median elongated bulge associated with mesethmoid terminating coequally with transversal through nares. Conspicuous ridge originating lateral to nares, passing through supraorbital, and extending to posterior portion of pterotic-supracleithrum. Supraoccipital bone with moderate to highly developed median ridge, and with relatively well-developed posterior process bordered by single wide plate. Exposed region of opercle small, not easily seen and usually with less than ten odontodes. Oral disk round, moderate in size. Lower lip not reaching transversal through gill openings, ventral surface covered with numerous small papillae decreasing in size posteriorly. Maxillary barbel moderately developed, almost equal in length to orbital diameter. Odontodes present over anterior surface of upper lip, just below snout. Medial buccal papillae absent. Maxilla straight. Jaws acutely angled, averaging less than 80�� between left and right dentary rami. Teeth spoon shaped, apparently unicuspid; mesial cusp massive and round; lateral cusp extremely reduced and usually fused to mesial cusp (similar to the condition found in Hypostomus ericae; Hollanda Carvalho & Weber, 2004: 640, fig. 4a). Body covered with five rows of moderately spinulose dermal plates, except for region surrounding dorsal-fin base and very small areas around pectoral- and pelvic-fin insertions and at urogenital opening. Specimen NUP 7474, 181.0 mm SL with well-developed nuptial odontodes along dorsal surface of body and fin rays (Fig. 2c). Predorsal region with two conspicuous keels; area between keels flat. Dorsal, middorsal, and median series of plates with keels supporting sharp odontodes. Mid-ventral series lacking sharp odontodes or having moderate odontodes. Dorsal series of lateral plates with keel from first plate to area just anterior to origin of adipose fin. Mid-dorsal series of lateral plates with keels from first plate to area just posterior to adipose fin; third plate with keel oriented upward. Median series of plates with moderately-developed keels to area just below posterior dorsal-fin base. Mid-ventral series of plates with moderate keels from first to fifth or sixth plate, then slightly arched to area below adipose fin. Ventral series of plates devoid of keels; posterior two plates deflected laterally. Ventral surface of head totally covered with platelets, except for region beneath lower lip. Abdomen completely covered with minute platelets in specimens larger than 120 mm SL. Preanal plate present. Dorsal fin II,7, its origin at vertical through midpoint between origins of pectoral and pelvic fin, or slightly posterior to that point. Dorsal-fin margin straight to slightly convex. Adipose-fin spine compressed and curved toward its base. Pectoral fin I,6, its posterior border straight. Pectoral-fin spine slightly curved posteriorly, covered with moderately developed odontodes; odontodes enlarged towards distal portion of spine and particularly in larger specimens. Specimen NUP 7474, 181.0 mm SL with strong hypertrophied odontodes on posterodorsal region of pectoral fin. Tip of adpressed pectoral fin reaching to anterior one-third of pelvic-fin spine length. Pelvic fin i,5, its posterior border slightly roundish. Adpressed pelvic-fin spine just reaching to or just surpassing anal-fin origin. Anal fin i,4, its tip reaching the fifth to sixth plate after its origin. Rays of anal fin progressively increasing in size, third branched ray usually the longest. Caudal fin i,14,i. Caudal-fin margin falcate; ventral lobe slightly longer than dorsal one. Color in alcohol. Overall ground color of dorsal and ventral regions of body and fins yellowish-brown. Dorsal surface of head and body covered by well-defined and moderately-set dark spots except on ventrolateral region of caudal peduncle. Spots on ventral surface uncommon, observed only in two specimens as scarce and sparsely arranged. Dorsal and pectoral fins with dark spots, mainly on proximal region and along spines and first branched rays. Pelvic fin with dark spots usually grouped on median region of branched rays. Anal fin usually lacking spots. Caudal fin with few distally, but usually lacking spots proximally; distal caudal-fin spots occasionally vertically aligned in two to three bands. Spot pattern with pronounced ontogenetic variation (Fig. 2). Marks typically larger, scarce and ill-defined on smaller specimens. Patches of pigmentation gradually forming welldefined spots during ontogenic growth. Dark spots generally large, few in number and widely spaced on specimens up to 45 mm SL; spots on fins sometimes fused forming transverse bands. Spots smaller, mores numerous and set closer on specimens up to 115 mm SL. Spots better outlined at this stage, especially on head and trunk. Spots progressively more numerous on head and trunk, and better outlined, including fins, up to specimens around 180 mm SL. Color in life. Live specimens with coloration similar to preserved ones, except for more brownish yellow coloration on body and fins (Fig. 3). Distribution. Hypostomus dardanelos is currently known from the rio Aripuan�� drainage, downstream cachoeira Dardanelos (Fig. 4). Etymology. The specific epithet, dardanelos, is a noun in reference to the cachoeira Dardanelos. A noun in apposition., Published as part of Zawadzki, Cl��udio H. & Carvalho, Pedro Hollanda, 2014, A new species of the Hypostomus cochliodon group (Siluriformes: Loricariidae) from the rio Aripuan�� basin in Brazil, pp. 43-51 in Neotropical Ichthyology 12 (1) on pages 44-49, DOI: 10.1590/S1679-62252014000100004, http://zenodo.org/record/4550951, {"references":["Fernandes, I. M., L. S. Lourenco, R. P. Ota, M. M. M. Moreira & C. H. Zawadzki. 2013. Effects of local and regional factors on the fish assemblage structure in Meridional Amazonian streams. Environmental Biology of Fishes, 96: 837 - 848.","Armbruster, J. W. 2003. The species of the Hypostomus cochliodon group (Siluriformes: Loricariidae). Zootaxa, 249: 1 - 60."]}

Hypostomus perdido, new species Figs. 1-2a,c Hypostomus sp. 2-Rio Perdido NUP 4249: Cereali et al., 2008: 587 (cytogenetic data, karyotype). Holotype. MZUSP 111064, 159.1 mm SL, Brazil, Mato Grosso do Sul, Bodoquena, rio Paraguai basin, rio Perdido, 21��17���09���S 56��41���47���W, 8 Sep 2005, O. Froehlich. Paratypes. All collected with the holotype (61 specimens). ANSP 193370, 2, 163.6 - 171.3 mm SL. CPUFMT 1500, 2, 152.5 - 170.3 mm SL. INPA 37689, 1, 144.4 mm SL. MCP 47141, 2, 133.9 - 147.9 mm SL. MNRJ 40094, 2, 126.0- 153.1 mm SL. NUP 12143, 10, 136.4 - 166.3 mm SL. NUP 12144, 18, 109.1 - 152.4 mm SL. NUP 14406, 1 c&s, 124.0 mm SL. ZSM 41828, 1, 149.5 mm SL. ZUEC 7254, 2, 140.2 - 141.7 mm SL. ZUFMS-PIS 1468, 20, 126.6 -181.0 mm SL. Diagnosis. Hypostomus perdido is distinguished from all congeners, except H. fonchii, by having unicuspid teeth (vs. bicuspid teeth). From H. fonchii it is distinguished by having fewer dermal plates in the median series of lateral plates (26- 27 vs. 28), fewer premaxillary teeth (7-10 vs. 18-21), fewer dentary teeth (8-13 vs. 18-25), a more depressed head (head depth 15.8-18.1% in SL vs. 19.1-22.0%), and by the presence of median buccal papilla (vs. its absence). Description. Measurements and counts in Table 1. Dorsal profile of head convex from tip of snout to supraoccipital posterior end; straight from that point to dorsal-fin origin. Head elevated and compressed. Snout narrow and compressed, covered by irregular series of several small plates. Mesethmoid forming conspicuous bulge from snout tip to nares. Upper orbital margin not elevated. Eye laterodorsally positioned. Interorbital region wide and flat in frontal view. Very slender keel on upper portion of pteroticsupracleithrum just posterior to orbit. Opercle considerably large and somewhat ellipsoidal; its horizontal length similar to orbital diameter; odontodes slightly larger on posterior margin. Predorsal region almost flat; usually with one single larger plate surrounding supraoccipital followed by two narrow plates in front of dorsal-fin spinelet. Dorsal profile of trunk tapering straight from dorsal-fin insertion to caudal peduncle posterior portion; ascending to caudal fin. Adipose fin long, almost same length of minimum caudal peduncle depth. Maximum body width at region of dorsal-fin origin; profile gradually tapering from this point to caudal fin. Caudal peduncle somewhat ellipsoid in cross-section; dorsal and ventral caudal peduncle region slightly flattened. Dorsal fin II,7; distal margin slightly convex to straight; origin at vertical two plates before pelvic-fin insertion; adpressed rays not reaching adipose-fin spine. Pectoral fin I,6; distal margin straight and almost reaching from one-third to half pelvic-fin length, odontodes more developed on distal dorsal region. Pelvic fin I,5; distal margin straight to slightly convex; distal portion of unbranched pelvic-fin ray reaching or slightly surpassing anal-fin insertion when adpressed to body. Anal fin I,5; distal border rounded. Caudal fin I,14,I, posterior margin truncate to slight emarginated; lower lobe slightly longer than upper lobe. Vertebrae 27; ribs 9, first rib relatively larger than others. Dorsal and lateral surface of head and body covered with dermal plates, except snout tip and area surrounding dorsal-fin base. Plates on lateral margin of head, from snout tip to pterotic-supracleithrum small and irregular. Five lateral series of plates on trunk. Dorsal, mid-dorsal, median, midventral and ventral series without keels. Lateral line complete on median lateral series. Mid-ventral series moderately bent on anterior portion. Ventral region of body with small platelets bearing odontodes, except area beneath lower lip, insertion of pectoral and pelvic fins, and anterior region of anus. Naked areas reduced on larger specimens. Lips round; covered with dense papillae, which decrease in size to distal border. Median buccal papilla sensu Armbruster (2003, fig. 3) present. Buccal skin internally bordering premaxilla and dentary with unorganized series of flat enlarged papillae (Fig. 2a,c). Maxillary barbel elongate and proximately joined to labial border by membrane; distal tip free. Premaxilla with 7 to 10 teeth, dentary 8 to 13 teeth; teeth robust, moderate in length, unicuspid, crown short and continuous to stalk (without notch between stalk and crown). Dentary rami straight and angled 82 to 94�� from each other (n = 20 specimens; mean = 85.8��)., Published as part of Zawadzki, Claudio H., Tencatt, Luiz F. C. & Froehlich, Ot��vio, 2014, A new unicuspid-toothed species of Hypostomus Lac��p��de, 1803 (Siluriformes: Loricariidae) from the rio Paraguai basin, pp. 97-104 in Neotropical Ichthyology 12 (1) on page 98, DOI: 10.1590/S1679-62252014000100010, http://zenodo.org/record/4551009, {"references":["Cereali, S. S., E. Pomini, R. Rosa, C. H. Zawadzki, O. Froehlich & L. Giuliano-Caetano. 2008. Karyotype description of two species of Hypostomus (Siluriformes, Loricariidae) of the Planalto da Bodoquena, Brazil. Genetics and Molecular Research, 7: 583 - 591.","Armbruster, J. W. 2003. The species of the Hypostomus cochliodon group (Siluriformes: Loricariidae). Zootaxa, 249: 1 - 60."]}

A new unicuspid-toothed armored catfish species of Hypostomus is described from the Bodoquena Plateau, rio Paraguai basin, Mato Grosso do Sul State, Brazil. The new species is distinguished from its congeners, with exception of H. fonchii, by having unicuspid teeth (vs.bicuspid teeth); from H. fonchii it is distinguished by having median series of lateral plates with 26-27 (vs. 28); by lower number of premaxillary and dentary teeth (7-10 vs. 18-21; 8-13 vs. 18-25, respectively); for possessing more depressed head (head depth 15.8-18.1% SL vs. 19.1-22.0% SL); and by the presence of median buccal papilla (vs. absence). Uma espécie nova de cascudo do gênero Hypostomus com dentes unicuspidados é descrita da Serra da Bodoquena, bacia do rio Paraguai, estado do Mato Grosso do Sul, Brasil. A espécie nova é distinta de suas congêneres, com exceção de H. fonchii, pela presença de dentes unicuspidados (vs. bicuspidados); de H. fonchii é distinta por apresentar a série mediana de placas laterais com 26-27 (vs. 28); pelo menor número de dentes pré-maxilares e no dentário (7-10 vs. 18-21; 8-13 vs. 18-25, respectivamente); por possuir cabeça mais deprimida (altura da cabeça 15.8-18.1% CP vs. 19.1-22.0% CP) e pela presença de papilas bucais medianas (vs.ausência).

The expression patterns of 14 enzymatic systems in skeletal muscle, liver and heart tissues of three species of Hypostomus from the Iguaçu River basin (Brazil) were investigated. Although the patterns were similar for the three species, different tissues showed differential expressions, and the data showed that differential tissue expressions of isoperoxidases may be due to preferential combination or association of polypeptide subunits. The detected patterns for SOD isozymes showed that the quaternary structures of these enzymes were in disagreement with the subunit number reported for the majority of other vertebrate groups. Tissue-specific restriction on heterotetramer formation also were described in LDH and MDHP isozymes. Thus, these tissue-specific gene expression character in the species of Hypostomus have the greatest potential to be recognized and applied in systematic studies among species of Hypostomus.

Epithelial gill cell morphology and distribution were investigated in the armored catfish, Hypostomus cf. plecostomus, which lives in soft ion-poor Brazilian freshwaters. Pavement cells are the most abundant type of cell on both filament and lamellar epithelia and there are a great number of mucous and chloride cells between them. Mucous cells are almost covered by adjacent pavement cells and have large packed granules showing electrondense differences. No mucous cells were found on the lamellar epithelium. Chloride cell were distributed throughout both epithelia and usually have large apical surface facing the external medium and may exhibit short and sparsely distributed microvilli. The presence of chloride cells on the lamellar epithelium may be an adaptation to low ion concentrations in the water, allowing for improved ion-transport capacity of the gill. The large size of these cells increases the water-blood barrier and may affect the transference of respiratory gases. However, the negative effect on the respiratory process may be minimized by this species' ability to resort to atmospheric air to fulfill its oxygen requirements.

Relationships between ovarian structure, oocyte structure/development, and parental care/life history strategies of six loricariid catfishes common in the upper Parana River, Brazil were examined with analysis of catch data, relative gonad weight, histology, and microscopy. Three life history strategies were observed. Loricariichthys platymetopon, Loricariichthys sp. And Loricaria sp. produce several small clutches of large eggs over a protracted spawning period. Males of these species guard their eggs and larvae, which are transported as a mass on the ventral surface of the male's body. Hypostomus ternetzi and Megalancistrus aculeatus produce the largest mature eggs and the smallest clutches relative to adult mass. The spawning periods of these species are short, and males guard their broods in excavations. Rhinelepis aspera has high fecundity, high relative mass of mature gonads (both sexes), small mature eggs, and broadcast spawning with no parental care. This species migrates to spawn over firm substrates in channel areas during a contracted period. Mature oocytes of external bearers had the thickest zona radiata, followed by the egg scatterer, and cavity nesters. The thickness of the zona radiata probably is an adaptation to protect the developing egg from injury from abrasion. The zona granulosa appeared to be associated with production of secretions responsible for egg adhesion, and this layer was thickest in mature oocytes of the cavity nesting species, followed by the external bearers. All six species have wide distributions in the Parana River, tributaries, floodplain lagoons, and the Itaipu Reservoir, but brood guarders tended to be most common in lentic habitats.

This paper reported two newly recorded species, Hypsibius convergens Urbanowicz, 1925 and Hypsibius hypostomus Bartos, 1935, of the genus Hypsibius (Tardigrada; Hypsibiidae) from China. Both species were collected from Taibai Mt, Shaanxi Province. All specimens are deposited at the College of Life Sciences, Shaanxi Normal University, China.

Some Hypostomus species were studied concerning the features of the karyotype structure and the constitutive heterochromatin. The karyotype of sp. F from the Sao Francisco river (Minas Gerais state, Brazil) is now described for the first time. A diversity in the diploid number, ranging from 2n=68 to 2n=80, as well as in the karyotype formulae, is evident in this fish group. Two types of heterochromatin, GC- and AT-rich, could be identified with the use of base-specific fluorochromes. In some species heterochromatic bands are mainly located on the centromeric and telomeric chromosomal regions, while in other species they are also observed at interstitial locations. Hypotheses concerning this heterochromatic distribuition in Hypostomus karyotypes are discussed. A case of supernumerary heterochromatic segment and a centric fusion appear to be related with two variant karyotypic formulae observed among specimens from the Mogi-Guacu and Sao Francisco rivers, respectively. The available data permit us to characterize a divergent karyotypic evolution among the Hypostomus species already analyzed, both at the macro- and microstructural levels, that is, their general karyotype organization and particular features related to chromosomal banding or staining, respectively.

Armoured catfish Hypostomus plecostomus were exposed to distilled water for 15 days. High chloride cell proliferation occurred on the filament and lamellar gill epithelia. The apical surface of the chloride cells (66% of cells in both epithelia) showed significant reduction in the aquatic environment which was characterized by the development of a sponge-like organization. The chloride cell response suggests that these features could create a microenvironment which may favour either the reduction of ion loss or ion uptake in a environment characterized by an absence of ions.

Allozyme electrophoresis analysis were performed in four species of Hypostomus (Loricariidae), H. albopunctatus, H. hermanni, H. regani, and Hypostomus sp. 1/NUP 5612 from the Ivai river, a tributary of the upper Parana river. The study of 14 loci revealed diagnostic characters and exclusive alleles in a low frequency. The heterozygosity ranged from 0.000 in H. albopunctatus to 0.199 in H. hermanni, which was higher than the heterozygosity in other samples of Hypostomus in literature, as well as in other fish groups. Hypostomus albopunctatus and H. regani revealed higher similarity (I = 0.804), while H. hermanni and Hypostomus sp. 1/NUP 5612 showed the least genetic identity (I = 0.569). All samples were genetically distinguished, despite there were several shared alleles. The FST value was 0.671, showing a high genetic differentiation among the samples. Hypostomus sp. 1/NUP 5612 was genetically distinguished from the three congeners by the loci Adh-A and G3pdh-B and by present rare exclusive alleles in other six enzymatic systems.

The potential of fish to transfer salmonellae from heterogeneous aquatic biofilms into feces was assessed in controlled aquarium studies with Suckermouth Catfish Hypostomus plecostomus and with biofilms inoculated with salmonellae. Neither the presence of catfish nor inoculation with salmonellae had detectable effects on the abundance of the microbial community. Densities of the microbial community were about 10(5) cells/mL in the water during a 1-week period, whereas densities of the microbial community increased 10-fold (10(6) to 10(7) cells/mg) in catfish feces during the same period. Salmonellae were detected by both quantitative polymerase chain reaction (qPCR) and situ hybridization in water samples immediately after inoculation, in numbers of about 10(4) cells/mL, representing up to 20% of the cells of the microbial community. Numbers decreased by three orders of magnitude within the first 3 d of the study, which represented only 0.01% of the community, and became undetectable after day 5. In catfish feces, numbers of Salmonella initially increased to up to 6% of the cells of the community but then declined. These results suggest that Salmonella are not biomagnified during gut passage, and thus, fish only provide a means for the translocation of this pathogen.

A diversidade da ictiofauna da bacia do rio Ivaí é altamente subestimada. O presente estudo teve como objetivo caracterizar a ictiofauna do rio Bonito, um tributário do rio Ivaí, bacia do alto rio Paraná, quanto à riqueza, diversidade e constância de espécies. Foram estabelecidos três locais de amostragem ao longo do gradiente longitudinal do rio: cabeceira, trecho médio e região de desembocadura próxima ao rio Ivaí. Três incursões de coleta foram feitas em cada unidade utilizando redes de espera de diferentes malhas, tarrafas e covos. A ictiofauna foi composta por 23 espécies, divididas em nove famílias e três ordens. Entre as espécies coletadas, três delas são possíveis novos registros para o alto rio Paraná e 12 para a bacia do rio Ivaí. A maior riqueza foi registrada no trecho inferior, onde foram encontradas 20 espécies, o qual também apresentou maior diversidade e menor dominância de espécies. No trecho médio do rio foram coletadas sete espécies e no trecho superior apenas uma. No baixo rio Bonito a maioria das espécies foram acessórias e no trecho médio cinco foram constantes e apenas uma acessória. O trecho médio apresentou maior dominância de espécies, com destaque para Hypostomus aff. ancistroides. O gradiente altitudinal foi um importante fator estruturador da assembleia de peixes do rio Bonito, delimitando as assembleias ao longo do gradiente longitudinal. The ichthyofauna diversity of the Ivaí river basin is largely underestimated. The present study aimed to characterize the fish fauna of the Bonito River, a tributary to the Ivaí River, upper Paraná river basin, in relation to richness, diversity and constancy. It was established three sampling sites along the longitudinal gradient of the river: headwater, medium stretch and mouth, at the point near the confluence to Ivaí river. Three collection expeditions were made in each site. Gill nets of different meshes, cast nets and traps were used. The ichthyofauna of the Bonito river was composed by 23 species, divided into nine families and three orders. Among the sampled species, three were possible new records for the upper Paraná river basin and 12 for the Ivaí river basin. The highest species richness was recorded in the lower stretch, where 20 species were found. In the middle section of the river, seven species were collected and just one species was captured at headwater. In the lower stretch it was also obtained the greatest diversity and lower species dominance. Additionally, in the lower Bonito river most of the species were incidental, whereas in the middle section five species were constant and only one was accessory. The middle section had the most dominant species, Hypostomus aff. ancistroides. The altitudinal gradient seems to determine the pattern of species distribution, delimiting the assemblages along longitudinal gradient of the river.

Hypostomus, a genus of Loricariidae, is one of the most diversified and widely distributed genera among fishes of South America (Weber 2003). It is the dominant genus of armoured catfish in Brazilian rivers (Weber 2003). Chromosomally, this group is highly diversified and studies of repetitive DNAs in these species are still in preliminary stages. Hypostomus karyotypes range from 54 chromosomes in H. plecostomus (Muramoto et al. 1968) to 84 chromosomes in Hypostomus sp. 2 (Cereali et al. 2008). Artoni and Bertollo (2001) consider the diploid number of 54 chromosomes as basal for Hypostominae, using Trichomycteridae as outgroup, suggesting that the chromosome evolution of Hypostomus occurred through centric fissions. Recently, Bueno et al. (2012) showed that other chromosomal rearrangements, such as inversions, deletions, duplications and heterochromatinization, could contribute to the chromosomal differentiation within the genus. Repetitive DNAs arranged in tandem are important tools in studies of taxonomic and evolutionary problems. These sequences could be associated with chromosomal rearrangement events (Wichman et al. 1991; Rosa et al. 2012; and others). According to Wichman et al. (1991), satellite DNAs rapidly diverge during evolution. Thereby, they are important for solving the taxonomic and evolutionary problems among related species.

Hypostomus delimai new species (Figs. 1- 3) Holotype. INPA 6191, 235.2 mm SL, Brazil, Par��, Itupiranga, rio Tocantins, 05��07���29.6���S 49��18���44.4���W, 14 Nov 1980, INPA ichthyological staff. Paratypes. Brazil: Par�� State: ANSP 192612, 1, 202.1 mm SL; INPA 35376, 3, 162.7 -230.0 mm SL. ZUEC 7088, 200.7 mm SL, collected with holotype. INPA 2485, 1, 175.4 mm SL, Tucuru��, rio Tocantins, 03��51���54.1���S 49��39���1.6���W, 31 Oct 1987, F. Martinho. INPA 6153, 1, 247.2 mm SL, Itupiranga, lago Morateiro, rio Tocantins, 05��08���42.1���S 49��18���10.2���W, 4 Jul 1982, INPA ichthyological staff. INPA 6192, 2, 206.0 and 253.1 mm SL, Itupiranga, rio Tocantins, 05��09���59.5���S 49��20���1.0���W, 30 Jun 1980, INPA ichthyological staff. INPA 6193, 4, 103.9 -215.0 mm SL. MPEG 24021, 1, 168.8 mm SL, Itupiranga, rio Tocantins, 05��05���26.3���S 49��20���13.9���W, 30 Jun 1980, INPA ichthyological staff. INPA 6195, 1, 147.8 mm SL, Itupiranga, rio Tocantins, 05��05���26.3���S 49��20���13.9���W, 30 Jun 1981, M. J��gu. MZUSP 110815, 1, 207.0 mm SL, S��o Geraldo do Araguaia, rio Gameleira, at its mouth, tributary to rio Araguaia, 06��08���11���S 48��23���35���W, 4 May 2009, T. Debona & C. H. Zawadzki. Tocantins State: INPA 20029, 1, 118.0 mm SL, Caseara, Parque Estadual do Cant��o, lago Volta Grande, rio Araguaia, 09��47���16���S 50��09���54.5���W, 18 May 2000, J. Zuanon, E. J. G. Ferreira, S. Amadio & G. M. Santos. INPA 20473, 1, 167.1 mm SL, Caseara, Parque Estadual do Cant��o, lago Perdidos, rio Araguaia, 09��42���59.9���S 50��08���14���W, 24 Feb 2000, J. Zuanon, E. J. G. Ferreira, S. Amadio & G. M. Santos. INPA 35376, 3, 162.7 -230.0 mm SL; and NUP 11015, 1, 204.3 mm SL, border of Anan��s and S��o Geraldo do Araguaia (in the border of the States of Tocantins and Par��), rio Araguaia, 06��08���14���S 48��19���52���W, 9 Jul 2009, T. Debona. NUP 11016, 1, 176.7 mm SL, Araguan��, rio Lontra, tributary to rio Araguaia, 06��33���56���S 48��38���11���W, 8 May 2009, T. Debona & C. H. Zawadzki. NUP 11017, 1, 205.5 mm SL, Anan��s, border of the States of Tocantins and Par��, rio Araguaia, 06��08���14���S 48��19���52���W, 8 May 2009, T. Debona & C. H. Zawadzki. Diagnosis. The new species is distinguished from all other Hypostomus species, with exception of H. carinatus (Steindachner, 1881), H. hoplonites Rapp Py-Daniel, 1988, and H. watwata Hancock, 1828, by the presence of five to eight (mode seven) predorsal plates limiting the posterior border of the supraoccipital bone (Fig. 3) (vs. one to three plates). Hypostomus delimai differs from H. carinatus, H. hoplonites, and H. watwata by having pale spots against darker ground color on body and fins (vs. dark spots against lighter ground color). Description. Based on holotype and 21 paratypes. Counts and measurements in Table 1. Head broad and slightly compressed. Body width at cleithral region slightly greater than head depth and approximately equal to head length. Snout and anterior profile of head weakly rounded in dorsal view. Snout in lateral profile rising from horizontal at approximately 45��. Dorsal profile nearly straight rising from snout tip to interorbital area, then rising slightly convex to dorsal-fin origin; sloped downward from dorsal-fin origin to region of dorsal procurrent caudal-fin rays, then elevating again to caudal-fin origin. Caudal peduncle somewhat ellipsoid in cross-section, dorsally and ventrally flattened. Eye moderate in diameter (14.1-17.1% of HL), dorsolaterally positioned. Interorbital area wide and flat in frontal view. Mesethmoid forming inconspicuous median ridge on dorsal region of snout. Weak ridge on dorsal surface of head, from nares to upper margin of eyes, and from here to compound pterotic. Cheek plates with odontodes usually small, but sometimes distinctively larger on posterior border. Cleithral process deep in lateral view, usually deeper than longer, its upper border convex. Supraoccipital generally with conspicuous median ridge; with narrow and relatively long posterior process limited by five to eight (mode seven) predorsal plates. Plates limiting supraoccipital as part of complex arrangement of platelets (Fig. 3). Dorsal and lateral surface of head and body covered with dermal plates, except for small unplated area on tip of snout and dorsal-fin base. Predorsal region flattened, with paired moderate ridges. Trunk covered by five lateral series of dermal plates. Dorsal series of plates keeled from dorsal-fin origin to adipose-fin origin, then weakly keeled until upper procurrent caudal-fin rays. Keeled plates of all series, except ventral, with longitudinal rows of odontodes clustered at middle of plates. Mid-dorsal series with longitudinal rows of odontodes complete. Median series bearing complete lateral line, complete row of hypertrophied odontodes. Mid-ventral series moderately bent, with slightly enlarged longitudinal rows of odontodes. Ventral series strongly flattened on anterior region of caudal peduncle, bent on posterior region, and without conspicuous hypertrophied odontodes. Mouth moderate in size with enlarged central buccal papilla; buccal papilla with distal portion usually fringed. Lips wide and round. Outer edge of upper lips with odontodes. Lower lip far from reaching gill opening, its inner surface covered with numerous small papillae, larger proximally. Maxillary barbel moderate in size, slightly shorter than orbital diameter. Teeth slender, with elongated main cusp and smaller lateral cusp. Intermandibular tooth row angle approximately from 100�� to 120��. Lower surface of head totally covered by platelets except area just beneath lower lip. Pectoral bridge and abdomen totally covered by platelets except small area at base of left and right pelvic-fin unbranched rays, respectively. Dorsal fin II,7; moderate in size; spine flexible; its border almost straight; posteriorly reaching spine of adipose fin. Adipose-fin spine well developed, curved inward, with distal tip usually reaching anteriormost dorsal procurrent ray. Pectoral fin I,6; spine not flexible, slightly curved, with rounded tip, and usually with hypertrophied odontodes, largest on distal portion in largest specimens; when adpressed almost reaching middle of pelvic-fin spine. Pelvic fin i,5; unbranched ray curved inward; when adpressed surpassing anal-fin unbranched-ray base; its border slightly rounded. Anal fin i,4; when adpressed, distal tip of posterior rays reaching seventh or eighth plate posterior to anal-fin origin. Caudal fin i,7+7,i; slightly emarginated, with ventral lobe equal to slightly longer than dorsal lobe. Color in alcohol. Ground color of dorsal surface of head and body grayish-brown. Head, dorsum and flanks covered with many pale spots against darker background. Pale spots dense, small, close to each other and less numerous, larger and more distant to each other from compound pterotic to caudal peduncle (Figs. 2 and 4). On flanks of some individuals pale spots with irregular format usually fused to each other, sometimes forming vermiculations (Fig. 1). Ventral region of head and abdomen slightly lighter than dorsal region in specimens up to 100.0 mm SL, in larger specimens ventral region of body similar to dorsal region. Some larger specimens with upper and lower lip dark. Dorsal, pectoral, pelvic, anal and caudal fins dark brown with pale round spots mainly over rays. Adipose fin dark brown with pale spots sometimes fused along spine (Figs. 1 and 5). Color in life. Color pattern similar to that observed in preserved specimens, except body and fins exhibiting greenbrown background and tan spots with green tinge (Fig. 2). Distribution and habitat. The species was found only in middle stretches of the rio Tocantins-Araguaia basin (Fig. 4). Records of the new species were done before the construction of Tucuru�� dam in the rio Tocantins and in the rio Araguaia, in a habitat that soon will be flooded by the construction of the Santa Isabel dam. The rio Araguaia has about 2,627 km long, and its headwaters are located near the Emas National Park, southeast of the Goi��s State, Brazil. The rio Araguaia flows northeast to a junction with the rio Tocantins near the town of S��o Jo��o do Araguaia in the State of Par��. These rivers have turbid water, rocky and sandy substrate, and variable remnant riparian vegetation. The new species was found cooccurring, with Squaliforma cf. emarginata (Valenciennes, 1840), Hypostomus faveolus, Hypostomus cf. plecostomus (Linnaeus, 1758), H. pyrineusi (Miranda Ribeiro, 1920), and another putative undescribed species of Hypostomus. Etymology. The specific epithet delimai is in honor of Fl��vio C��sar Thadeo de Lima, Brazilian ichthyologist, due to his numerous contributions to Neotropical ichthyology., Published as part of Zawadzki, Cl��udio Henrique, Oliveira, Renildo Ribeiro de & Debona, Tiago, 2013, A new species of Hypostomus Lac��p��de, 1803 (Siluriformes: Loricariidae) from the rio Tocantins-Araguaia basin, Brazil, pp. 73-80 in Neotropical Ichthyology 11 (1) on pages 74-77, DOI: 10.1590/S1679-62252013000100008, http://zenodo.org/record/4566852

Hypostomus delimai new species (Figs. 1- 3) Holotype. INPA 6191, 235.2 mm SL, Brazil, Pará, Itupiranga, rio Tocantins, 05°07’29.6”S 49°18’44.4”W, 14 Nov 1980, INPA ichthyological staff. Paratypes. Brazil: Pará State: ANSP 192612, 1, 202.1 mm SL; INPA 35376, 3, 162.7 -230.0 mm SL. ZUEC 7088, 200.7 mm SL, collected with holotype. INPA 2485, 1, 175.4 mm SL, Tucuruí, rio Tocantins, 03°51’54.1”S 49°39’1.6”W, 31 Oct 1987, F. Martinho. INPA 6153, 1, 247.2 mm SL, Itupiranga, lago Morateiro, rio Tocantins, 05°08’42.1”S 49°18’10.2”W, 4 Jul 1982, INPA ichthyological staff. INPA 6192, 2, 206.0 and 253.1 mm SL, Itupiranga, rio Tocantins, 05°09’59.5”S 49°20’1.0”W, 30 Jun 1980, INPA ichthyological staff. INPA 6193, 4, 103.9 -215.0 mm SL. MPEG 24021, 1, 168.8 mm SL, Itupiranga, rio Tocantins, 05°05’26.3”S 49°20’13.9”W, 30 Jun 1980, INPA ichthyological staff. INPA 6195, 1, 147.8 mm SL, Itupiranga, rio Tocantins, 05°05’26.3”S 49°20’13.9”W, 30 Jun 1981, M. Jégu. MZUSP 110815, 1, 207.0 mm SL, São Geraldo do Araguaia, rio Gameleira, at its mouth, tributary to rio Araguaia, 06°08’11”S 48º23’35”W, 4 May 2009, T. Debona & C. H. Zawadzki. Tocantins State: INPA 20029, 1, 118.0 mm SL, Caseara, Parque Estadual do Cantão, lago Volta Grande, rio Araguaia, 09°47’16”S 50°09’54.5”W, 18 May 2000, J. Zuanon, E. J. G. Ferreira, S. Amadio & G. M. Santos. INPA 20473, 1, 167.1 mm SL, Caseara, Parque Estadual do Cantão, lago Perdidos, rio Araguaia, 09°42’59.9”S 50°08’14”W, 24 Feb 2000, J. Zuanon, E. J. G. Ferreira, S. Amadio & G. M. Santos. INPA 35376, 3, 162.7 -230.0 mm SL; and NUP 11015, 1, 204.3 mm SL, border of Ananás and São Geraldo do Araguaia (in the border of the States of Tocantins and Pará), rio Araguaia, 06°08’14”S 48°19’52”W, 9 Jul 2009, T. Debona. NUP 11016, 1, 176.7 mm SL, Araguanã, rio Lontra, tributary to rio Araguaia, 06º33’56”S 48º38’11”W, 8 May 2009, T. Debona & C. H. Zawadzki. NUP 11017, 1, 205.5 mm SL, Ananás, border of the States of Tocantins and Pará, rio Araguaia, 06°08’14”S 48°19’52”W, 8 May 2009, T. Debona & C. H. Zawadzki. Diagnosis. The new species is distinguished from all other Hypostomus species, with exception of H. carinatus (Steindachner, 1881), H. hoplonites Rapp Py-Daniel, 1988, and H. watwata Hancock, 1828, by the presence of five to eight (mode seven) predorsal plates limiting the posterior border of the supraoccipital bone (Fig. 3) (vs. one to three plates). Hypostomus delimai differs from H. carinatus, H. hoplonites, and H. watwata by having pale spots against darker ground color on body and fins (vs. dark spots against lighter ground color). Description. Based on holotype and 21 paratypes. Counts and measurements in Table 1. Head broad and slightly compressed. Body width at cleithral region slightly greater than head depth and approximately equal to head length. Snout and anterior profile of head weakly rounded in dorsal view. Snout in lateral profile rising from horizontal at approximately 45º. Dorsal profile nearly straight rising from snout tip to interorbital area, then rising slightly convex to dorsal-fin origin; sloped downward from dorsal-fin origin to region of dorsal procurrent caudal-fin rays, then elevating again to caudal-fin origin. Caudal peduncle somewhat ellipsoid in cross-section, dorsally and ventrally flattened. Eye moderate in diameter (14.1-17.1% of HL), dorsolaterally positioned. Interorbital area wide and flat in frontal view. Mesethmoid forming inconspicuous median ridge on dorsal region of snout. Weak ridge on dorsal surface of head, from nares to upper margin of eyes, and from here to compound pterotic. Cheek plates with odontodes usually small, but sometimes distinctively larger on posterior border. Cleithral process deep in lateral view, usually deeper than longer, its upper border convex. Supraoccipital generally with conspicuous median ridge; with narrow and relatively long posterior process limited by five to eight (mode seven) predorsal plates. Plates limiting supraoccipital as part of complex arrangement of platelets (Fig. 3). Dorsal and lateral surface of head and body covered with dermal plates, except for small unplated area on tip of snout and dorsal-fin base. Predorsal region flattened, with paired moderate ridges. Trunk covered by five lateral series of dermal plates. Dorsal series of plates keeled from dorsal-fin origin to adipose-fin origin, then weakly keeled until upper procurrent caudal-fin rays. Keeled plates of all series, except ventral, with longitudinal rows of odontodes clustered at middle of plates. Mid-dorsal series with longitudinal rows of odontodes complete. Median series bearing complete lateral line, complete row of hypertrophied odontodes. Mid-ventral series moderately bent, with slightly enlarged longitudinal rows of odontodes. Ventral series strongly flattened on anterior region of caudal peduncle, bent on posterior region, and without conspicuous hypertrophied odontodes. Mouth moderate in size with enlarged central buccal papilla; buccal papilla with distal portion usually fringed. Lips wide and round. Outer edge of upper lips with odontodes. Lower lip far from reaching gill opening, its inner surface covered with numerous small papillae, larger proximally. Maxillary barbel moderate in size, slightly shorter than orbital diameter. Teeth slender, with elongated main cusp and smaller lateral cusp. Intermandibular tooth row angle approximately from 100° to 120°. Lower surface of head totally covered by platelets except area just beneath lower lip. Pectoral bridge and abdomen totally covered by platelets except small area at base of left and right pelvic-fin unbranched rays, respectively. Dorsal fin II,7; moderate in size; spine flexible; its border almost straight; posteriorly reaching spine of adipose fin. Adipose-fin spine well developed, curved inward, with distal tip usually reaching anteriormost dorsal procurrent ray. Pectoral fin I,6; spine not flexible, slightly curved, with rounded tip, and usually with hypertrophied odontodes, largest on distal portion in largest specimens; when adpressed almost reaching middle of pelvic-fin spine. Pelvic fin i,5; unbranched ray curved inward; when adpressed surpassing anal-fin unbranched-ray base; its border slightly rounded. Anal fin i,4; when adpressed, distal tip of posterior rays reaching seventh or eighth plate posterior to anal-fin origin. Caudal fin i,7+7,i; slightly emarginated, with ventral lobe equal to slightly longer than dorsal lobe. Color in alcohol. Ground color of dorsal surface of head and body grayish-brown. Head, dorsum and flanks covered with many pale spots against darker background. Pale spots dense, small, close to each other and less numerous, larger and more distant to each other from compound pterotic to caudal peduncle (Figs. 2 and 4). On flanks of some individuals pale spots with irregular format usually fused to each other, sometimes forming vermiculations (Fig. 1). Ventral region of head and abdomen slightly lighter than dorsal region in specimens up to 100.0 mm SL, in larger specimens ventral region of body similar to dorsal region. Some larger specimens with upper and lower lip dark. Dorsal, pectoral, pelvic, anal and caudal fins dark brown with pale round spots mainly over rays. Adipose fin dark brown with pale spots sometimes fused along spine (Figs. 1 and 5). Color in life. Color pattern similar to that observed in preserved specimens, except body and fins exhibiting greenbrown background and tan spots with green tinge (Fig. 2). Distribution and habitat. The species was found only in middle stretches of the rio Tocantins-Araguaia basin (Fig. 4). Records of the new species were done before the construction of Tucuruí dam in the rio Tocantins and in the rio Araguaia, in a habitat that soon will be flooded by the construction of the Santa Isabel dam. The rio Araguaia has about 2,627 km long, and its headwaters are located near the Emas National Park, southeast of the Goiás State, Brazil. The rio Araguaia flows northeast to a junction with the rio Tocantins near the town of São João do Araguaia in the State of Pará. These rivers have turbid water, rocky and sandy substrate, and variable remnant riparian vegetation. The new species was found cooccurring, with Squaliforma cf. emarginata (Valenciennes, 1840), Hypostomus faveolus, Hypostomus cf. plecostomus (Linnaeus, 1758), H. pyrineusi (Miranda Ribeiro, 1920), and another putative undescribed species of Hypostomus. Etymology. The specific epithet delimai is in honor of Flávio César Thadeo de Lima, Brazilian ichthyologist, due to his numerous contributions to Neotropical ichthyology.

Hypostomus delimaiis described from the rio Tocantins, Tocantins State, and from the rio Araguaia, Pará, and Tocantins States, Brazil. The new species is distinguished from all other Hypostomusspecies, except from H. carinatus, H. hoplonites, and H. watwata, by the presence of five to eight (mode seven) predorsal plates limiting posterior border of the supraoccipital bone (vs. one to three plates). It can be distinguished from H. carinatus, H. hoplonites, and H. watwata by having pale spots over darker background on body and fins (vs. dark spots over lighter background). The species was only found in the middle stretches of the rio Tocantins-Araguaia basin. The first collection of specimens assigned to the new species was done in the rio Tocantins before the construction of the Tucuruí dam. Recently additional material was collected in the rio Araguaia, in a habitat that soon will be flooded for the construction of the Santa Isabel hydroelectric power station. Hypostomus delimai é descrita do rio Tocantins no estado do Tocantins e do rio Araguaia, entre os estados do Pará e Tocantins, Brasil. A espécie nova é diagnosticada das demais espécies de Hypostomus, com exceção de H. carinatus, H. hoplonites e H. watwata por possuir de cinco a oito (moda sete) placas pré-dorsais margeando a borda posterior do supraoccipital (vs.uma ou até três placas). Difere de H. carinatus, H. hoplonites, e H. watwata por apresentar pintas claras sobre o corpo e nadadeiras (vs. pintas escuras sobre fundo claro). A espécie nova foi encontrada somente no trecho médio da bacia do rio Tocantins-Araguaia. Os primeiros registros da espécie nova foram feitos no rio Tocantins antes da construção da barragem de Tucuruí. Recentemente, material adicional foi coletado no rio Araguaia, em um habitat que será brevemente inundado pela construção da hidrelétrica de Santa Isabel.

Gill respiratory surface area and oxygen consumption during aquatic respiration were measured in the facultative air-breathing loricariid fish,Hypostomus plecostomus. The fish did not surface to breathe atmospheric air in normoxic water; air-breathing was evoked by environmental hypoxia (water oxygen tension=35±2, mmHg) and did not show size-related threshold differences for air breathing.During gradual hypoxia, without access to atmospheric, air,H. plecostomus was found to be an oxyregulator and showed a reduced range of water oxygen tension in which the oxygen consumption remained constant in smaller fish. The critical oxygen tensions were 55 and 33 mmHg at 25°C for fish of 14-30 g and 31-80g body weight, respectively.The gill respiratory surface area (total lamellae area) is reduced, however, the lamellar frequency per mm of gill filament is high which facilitates the gas exchange. Moreover, the increase of gill respiratory surface area (b=0.666) is higher than the increase in routine VO2 (b=0.338) showing a positive relationship between the gill respiratory surface area /VO2 ratio and body mass (b=0.328); this indicates that the fish have greater gill respiratory surface area per unit of routine VO2 as they grow.

SUMMARYSome species of Hypostomus from the Upper Parana Basin (SP) were studied cytogenetically. The diploid chromosome number ranged from 2n= 68 to 2n = 80, with a considerably variable karyotypic structure between species, but no chromosomal differences were observed between males and females. The nucleolar organizer regions (NORs) were also quite variable both intra- and interspecifically in terms of number and size. In general, constitutive heterochromatin was not very abundant and usually located in small blocks. The data suggest that some chromosomal rearrangements, as the robertsonian ones and pericentric inversions, were important for the karyotypic evolution of Hypostomus. These fishes also appear to be a good material for cytotaxonomic studies.

Laboratory-based static acute toxicity tests were performed to determine the relative toxicity of TFM to selected species of tadpoles and ornamental fish in soft (mean, 45 mg/L as CaCO3) and hard (mean, 177 mg/L) freshwater. Sensitivity was measured as the 96-h LC50, the concentration lethal to half the test animals in 96 h, The sensitivity of larval bullfrogs Rana catesbeiana to TFM was 1.50 mg/L in soft water and 4.20 mg/L in hard water. The 96-h LC50 of TFM for larval southern toads Bufo terrestris was 0.51 mg/L in soft water and 0.70 mg/L in hard water. Toxicity of TFM (96-h LC50) to the fish tested ranged from 1.02 to 7.73 mg/L in soft water and 1.83 to 18.05 mg/L in hard water. Probit analysis indicated that the amount of TFM required to kill 99% of bullfrog larvae was 3.35 mg/L. A 96-h exposure to 3.35 mg!L TFM would also kill 99% of suckermouth catfish Hypostomus plecostomus, 92% of black neon tetras Hyphessobrycon herbertaxelrodi, 90% of tiger barbs Puntius tetrazona, 50% of freshwater a...

The structural organization of the interbranchial septum of the gill arch of the air-breathing loricariid fish Hypostomus plecostomus was examined using light and electron microscopy. In the middle of the interbranchial septum, an extensive interconnection was found between the afferent primary arteries from successive and opposing primary lamellae. The blood circulates among numerous trabeculae consisting of connective tissue, smooth muscle cells, and collagen fibres. A sheet of smooth muscle cells is localized at the borders of these interconnected primary arteries and joins the cartilage rod from one primary lamella to the adjacent one on the same hemibranch. The adductor muscles are restricted to the distal end of the interbranchial septum and consist of transverse and oblique striated muscle fibres fixed to the cartilage rod from the primary lamella of opposite hemibranchs. The arrangement of these muscle fibres suggests a double movement of adduction: approximation of the tips of the primary lamellae of opposing hemibranchs and reduction of the space between adjacent primary lamellae of the same hemibranch. The action of both smooth and striated muscles reduces the interconnecting vascular septal space between the primary arteries, which may allow fine adjustment of vascular perfusion of the distal part of the filaments as an adaptation for better blood flow under hypoxic conditions.

Length-frequency analyses showed that male Hypostomus affinis are bigger than females, but H. luetkeni showed no such differences. The sex ratio was estimated at 1:1 for both species. The temporal variation of sex ratio indicated a decrease in the male population when GSI was at its maximum value, suggesting that males are less prone to capture during the spawning season. According to the decrease of males during the reproductive period, paternal behaviour is proposed for both species. H. affinis reached sexual maturity at a smaller size than H. luetkeni. Considering the length weight relationship and the mortality rate of the reproductive females in both species, the physiological consequences of delay or precocity of the first maturation are discussed.

A study had been carried out to investigate heavy metal (Cu, Cd, Pb) content in sapu-sapu fish (hypostomus plecostomus) in Bengawan Solo river. The type of this research was observational research, with sapu-sapu fish inhabit Bengawan Solo River as the population. The samples were taken with purposive random sampling. Nine sapu-sapu fishes taken from 3 places, i.e.: Nguter Sukoharjo area, Premulung river outlet and Anyar river, 3 fishes from each palce, and then take examined the content of heavy metal. The result of study showed that the average content of Cu: 0.027 mg/100gr, Cd: 0.005 mg/100gr and Pb: 0.042 mg/100gr. Hence, sapu-sapu fish in Be3ngawan Solo had been contaminated with heavy metal (Cu, Cd, and Pb) and should not be consumed.

The adductor muscles in the gills of loricariid fish of genus Hypostomus and Rhinelepis are restricted to the distal end of the interbranchial septum. These muscles in Hypostomus comprise longitudinal and oblique striated muscle fibres.

A small-bodied new species of Hypostomus is described from the rio Itapicuru basin, Bahia, Brazil. The new species is distinguished from most congeners mainly by having the lower caudal-fin lobe distinctly longer than the upper lobe and absence of conspicuous dark spots on posterior half of body. It differs particularly from congeners occurring in northeastern coastal Brazilian drainages and the rio Sao Francisco basin by having the anterior portion of the abdomen completely plated and the posterior portion plated only on a narrow median line, leaving large lateral areas naked, dark spots on anterior portion of trunk similar in size or slightly larger than those on head, absence of conspicuous spots on posterior half of trunk and caudal fin, and absence of keels on head and trunk.

We review the complex history of those species included in the Hypostomus emarginatus species complex and recognize them in Isorineloricaria and Aphanotorulus . Isorineloricaria consists of four valid species: I. acuarius n. sp., I. spinosissima, I. tenuicauda, and I. villarsi . Aphanotorulus consists of six valid species: A. ammophilus, A, emarginatus, A. gomesi, A. horridus, A. phrixosoma, and A. unicolor. Plecostomus annae and Hypostoma squalinum are placed in the synonymy of A. emarginatus ; Plecostomus biseriatus , P. scopularius , and P. virescens are placed in the synonymy of A. horridus; Plecostomus winzi is placed in the synonymy of I. tenuicauda , and one new species, I. acuarius is described from the Apure River basin of Venezuela. Aphanotoroulus can be distinguished from Isorineloricaria by having caudal peduncles that do not become greatly lengthed with size and that are oval in cross section (vs. caudal peduncle proportions that get proportionately longer with size and that become round in cross-section), and by having small dark spots (less than half plate diameter) on a light tan background (vs. spots almost as large as lateral plates on a nearly white background.

O zinco (Zn) é considerado indispensável para o funcionamento de muitas atividades celulares nos peixes. Entretanto, quando em excesso, pode tornar-se nocivo ao organismo. A bioacumulação de Zn nos peixes é uma ferramenta importante para avaliação da poluição ambiental. Diante deste contexto, objetivou-se dosar os teores de Zn nas brânquias, carcaça, fígado e musculatura de 68 peixes (totalizando 272 amostras) das espécies Hoplias sp., Hypostomus sp., Piaractus sp., Pimelodus sp. e Prochilodus sp., capturados em cinco distintos pontos do Rio São Francisco (Minas Gerais) no ano de 2008. A área de estudo compreendeu a região de Três Marias, desde o Reservatório da Usina Hidrelétrica da CEMIG até a foz do rio Abaeté. Vinte e oito animais apresentaram concentrações de Zn acima do permitido pela legislação brasileira (50,00 mg/kg) em pelo menos uma de suas vísceras. Do total das 272 amostras avaliadas, 50 (18,38%) estavam inadequadas. As espécies Hoplias sp. e Hypostomus sp. apresentaram a maior bioacumulação de Zn no fígado e na carcaça. O valor médio de Zn na musculatura foi de 6,82 +- 3,00 mg/kg, ou seja, todas amostras de musculatura apresentaram baixos valores deste metal. Não houve diferença na concentração do Zn entre os cinco pontos estudados. Conclui-se que o tecido hepático da espécie de peixe Hoplias sp., é o melhor biomarcador da contaminação de Zn.Palavras-chave: Zinco, peixe, Rio São Francisco.ABSTRACT: ZINC EVALUATION IN GILLS, CARCASS, LIVER AND MUSCLE OF DIFFERENT FISH SPECIES CAUGHT IN SÃO FRANCISCO RIVER (MG, BRAZIL). The Zinc (Zn) is considered indispensable for the functioning of many cellular activities in fish. However, in high levels, zinc may become harmful. The bioaccumulation of Zn in fish is an important tool for assessing environmental pollution. In this context, the aim of the study was to dose the levels of Zn in gills, carcass, liver and muscle of 68 fish (total 272 samples) of: Hoplias sp., Hypostomus sp., Piaractus sp., Pimelodus sp. and Prochilodus sp., caught in five different parts of the São Francisco River (Minas Gerais) in 2008. The studied area covered the region of Três Marias, between CEMIG hydroelectric power plant reservoir and Abaeté River. Twenty-eight animals showed Zn concentrations above the limit level allowed by Brazilian legislation (50 mg/kg) in at least one of its tissues. Out of 272 samples tested, 50 (18.38%) were inadequate. The fish Hoplias sp. and Hypostomus sp. presented the highest bioaccumulation of Zn in liver and carcass. The mean value of Zn in the muscle was 6.82 +- 3.00 mg/kg, which means, all muscle samples showed low levels of this metal. There was no difference in Zn concentration among the five locations studied. It was concluded that the liver of the fish specie Hoplias sp. is the best biomarker of Zn contamination.Keywords: Zinc, fish, São Francisco River.

Loricariidae (Siluriformes, Hypostominae) is one of the most diverse catfish families. In spite of the wide distribution of loricariids in South America, cytogenetic reports are available for only a few species, mostly from southern and southeastern Brazil. We made the first chromosomal analysis of Hypostomus aff. unae from the Contas River basin in northeastern Brazil. Four populations isolated by short distances but from distinct landscapes were studied based on conventional staining, C-banding, argyrophilic nucleolar organizer regions (Ag-NOR), CMA(3)/DAPI fluorochrome staining, and fluorescent in situ hybridization with 18S rDNA probes. Although sharing the same diploid number (2n = 76) and NOR locations, each population presented exclusive karyotype formulae and specific patterns of heterochromatic and AT-rich regions. The derived karyotypes of H. aff. unae (2n >54; high number of acrocentrics bearing AT-rich interstitial heterochromatin) indicated a divergent karyoevolution, mostly driven by centric fissions, pericentric inversions and particular heterochromatin dispersion models. This finding of distinct evolutionary units in H. aff. unae will be useful for understanding the natural history of loricariids from relatively unexplored coastal basins in South America.

Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-27T11:26:27Z No. of bitstreams: 0Bitstream added on 2014-05-27T14:42:13Z : No. of bitstreams: 1 2-s2.0-84859169365.pdf: 2551591 bytes, checksum: a386cc8e20c36820fa37034ae15df718 (MD5) Made available in DSpace on 2014-05-27T11:26:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-04-04 Cytogenetic analyses were performed in four species of the Hypostominae subfamily, three from Hypostomus (Hypostomini) genus and Rhinelepis aspera (Rhinelepini). Three populations of Hypostomus ancistroides were analyzed, which had 2n=68 chromosomes, but presented different karyotype formulas. Hypostomus regani and H. strigaticeps, both from Ivaí river, showed 2n=72 chromosomes with two distinct cytotypes. In turn, R. aspera of the upper Paraná river basin presented 2n=54 chromosome. Multiple Nucleolar Organizer Regions (NORs) have been evidenced by silver nitrate staining in species of Hypostomus and single NOR in R. aspera. The observed variation in the chromosome number and the marked variability in karyotype formulas and NORs reveal a certain amount of karyotype variation in the genus Hypostomus suggesting the probable existence of cryptic species with independent chromosome traits. Therefore, our data can be of great value in discriminating species and understanding their chromosomal evolution. Departamento de Biologia Centro de Ciências Biológicas Universidade Estadual de Maringá, Av. Colombo, 5790, 87020-900, Maringá, Paraná Departamento de Morfologia Instituto de Biociências Universidade Estadual Paulista Júlio de Mesquita Filho, Botucatu, São Paulo Departamento de Morfologia Instituto de Biociências Universidade Estadual Paulista Júlio de Mesquita Filho, Botucatu, São Paulo

Cytogenetic analyses were performed in four species of the Hypostominae subfamily, three from Hypostomus (Hypostomini) genus and Rhinelepis aspera (Rhinelepini). Three populations of Hypostomus ancistroides were analyzed, which had 2n=68 chromosomes, but presented different karyotype formulas. Hypostomus regani and H. strigaticeps , both from Ivai river, showed 2n=72 chromosomes with two distinct cytotypes. In turn, R. aspera of the upper Parana river basin presented 2n=54 chromosome. Multiple Nucleolar Organizer Regions (NORs) have been evidenced by silver nitrate staining in species of Hypostomus and single NOR in R. aspera . The observed variation in the chromosome number and the marked variability in karyotype formulas and NORs reveal a certain amount of karyotype variation in the genus Hypostomus suggesting the probable existence of cryptic species with independent chromosome traits. Therefore, our data can be of great value in discriminating species and understanding their chromosomal evolution.

La région des Néotropiques abrite la plus grande diversité de poissons d'eau douce au monde, mais les forces évolutives ayant conduit à une telle diversité sont encore aujourd'hui très méconnues. Dans le but de comprendre la diversification au sein de la région des Guyanes, j'ai réalisé des études phylogénétiques de larges échantillonages guyanais et amazoniens des espèces de poissons-chats néotropicaux des genres Ancistrus et Hypostomus. Des phylogénies moléculaires basées sur un marqueur mitochondrial et deux marqueurs nucléaires, ainsi que sur des données concaténées, ont été établies. Celles-ci révèlent la présence d'un ou plusieurs clades d'origine guyanaise. Dans l'étude d'Ancistrus, de nouvelles espèces cryptiques ont été génétiquement révélées. J'ai également identifié plusieurs hybrides au sein du genre Ancistrus en me basant sur la comparaison d'arbres phylogénétiques des différents marqueurs, une approche PCR-RFLP ayant été utilisée par la suite pour distinguer les individus hybrides des non-hybrides. Ces méthodes m'ont permis d'identifier des individus non-hybrides permettant d'inférrer l'histoire évolutive des espèces. Dans l'analyse d'Ancistrus, l'interprétation des arbres phylogénétiques moléculaires m'a permis de proposer une hypothèse sur la voie d'entrée des ancêtres des différents clades guyanais de ces deux genres et sa dispersion ultérieure dans les rivières de la région des Guyanes. En effet, outre avoir démontré que chaque espèce occupe différents bassins fluviaux non-chevauchants, j'ai démontré l'intervention d'un événement de colonisation unique depuis le bassin du fleuve Amazone vers les fleuves côtiers des Guyanes via le fleuve Maroni. Quant à l'histoire de la dispersion des représentants Hypostomus, deux voies d'entrée distinctes ont été révlés, le premier est partagé avec Ancistrus, via le fleuve Maroni, et le second s'est fait par le fleuve Essequibo. Des méthodes comparatives d'arbres – Brooks parcimony Analysis et Maximum Agreement Subtree – ont appliquées aux arbres obtenus pour Hypostomus et Ancistrus, et j'ai également utilisé la phylogénie publiée antérieurement pour le complexe d'espèces Pseudancistrus brevispinis, qui présentait une hypothèse de colonisation similaire à celles que j'ai établies pour Hypostomus et Ancistrus. Ces analyses ont révélé un pattern de colonisation identique pour les trois genres étudiés, avec une entrée unique depuis le bassin du fleuve Amazone vers la partie haute de la rivière Maroni dans les Guyanes. Cette étude représente une contribution à la connaissance des genres Hypostomus et Ancistrus, ainsi que sur les processus de diversification, tels que les captures de rivières ou les « sea-level fuctuations », qui ont mené à une diversité élevée des poissons au sein des Guyanes. Ce travail apporte également de nouvelles perspectives dans les démarches d'analyses biogéographiques entre organismes présentant des aires de distribution similaires, ainsi que l'identification d'hybrides au sein d'un genre particulier.

Two major Manila esteros, the Estero de San Miguel and Estero de Quiapo, were studied to determine their ecological status. Analyses of physicochemical parameters of the esteros – turbidity, temperature, salinity, EC, pH, DO, BOD, COD,TKN, TP, chl-a, and oil and grease- showed the estero waters fall under Class D water quality criterion. TKN and TP values indicated hypertrophic conditions AT all stations. Low chl-a values were indicative of stressful conditions to the primary producers. Mean differences of most of the parameters differed significantly between stations and season. Four fish, Rasbora maculata (Kataba), Gambusia affinis (Mosquito Fish), Anabas testudineus (Climbing perch) and Hypostomus plecostomus (Janitor fish), with Rasbora and Gambusia inhabit the esteros. Fish communities exhibited high evenness but low in dominance and diversity. 19 phytoplankton genera - Cyanophyta (3 spp), Chlorophyta (9 spp) and Bacillariophyta (7 spp) thrived in the esteros. A socioeconomic study revealed that attitudes and actions of stakeholders to their esteros were influenced primarily by economic status, and educational and cultural background. Survey also showed the awareness of the communities on the problems of esteros and their willingness to cooperate to rehabilitate their polluted river system. Institutional initiatives such as environmental education and community-based programs were examined as possible approaches towards effective rehabilitation and attainment of sustainability of Manila esteros

Microvascular parameters as well as respiratory and cardiac rates were measured in the freshwater catfish Hypostomus cf. punctatus . Unanesthetized animals were kept in a box with flowing water. Microcirculation of the pectoral fin was studied using a closed-circuit television system coupled to a microscope. In the first order venules, diameter and red blood cell (RBC) velocity averaged (mean ± SD) 37.2 ± 14.5 μ m and 0.63 ± 0.40 mm/sec, respectively. Second order venules had values of 22.8 ± 5.6 μ m and 0.45 ± 0.32 mm/sec. Arterioles (diameter = 4.7 ± 4.0 μ m) emerging from the soft rays had RBC velocities ranging from 0.04 to 2.31 mm/sec with a mean of 1.25 ± 0.87 mm/sec. Capillary diameter and RBC velocity averaged 6.0 ± 1.8 μ m and 0.15 ± 0.09 mm/sec, respectively. Some observations were also made on the secondary system of blood vessels.

Financiadora de Estudos e Projetos Conventional and molecular cytogenetic analysis were performed on 15 species of the subfamily Hypostominae, comprising 12 species of the Hypostomini tribe, genus Hypostomus, and three of the Ancistrini tribe, genera Ancistrus and Hemiancistrus. The chromosome number of 2n=52 was observed for Ancistrus multispinis (14m+14sm+24st-a), A. brevipinnis (14m+14sm+24st-a) and Hemiancistrus punctulatus (14m+26sm+12st-a). The nucleolar organizer regions (Ag-NORs) and 18S rDNA sites are simple and terminal for species, A. brevipinnis, A. multispinis and H. punctulatus. In these species, it can be seen that the NORs are also CMA3+/DAPI-. As for the heterochromatin, H. punctulatus showed a small amount of this chromosome component, while A. multispinis and A. brevipinnis showed a larger amount, with large blocks on the long arm of some st-a pairs. In turn, the different species of Hypostomus showed a variation from 64 to 82 chromosomes, exhibiting differences in the karyotype formula between species. The NORs were multiple for most species analyzed, with different phenotypes observed in the number and position, which was also confirmed by FISH analysis, showing an interindividual and interspecific variability. In all species, the NORs were also CMA3+/DAPI _. The heterochromatin pattern distribution was different in each species, being another important chromosome marker. Cytogenetic, molecular, and morphometry analysis were performed in the species Hypostomus albopunctatus (Piracicaba river, SP) and H. heraldoi (Pirapitinga river, GO), including those morphologically similar samples present in the Mogi Guaçu river (SP). All individuals had 2n=74, whereas H. albopunctatus showed 10m+20sm+44st-a and H. heraldoi 8m+20sm+46st-a. These two karyotype formulae were found in the Mogi Guaçu river population. Distinct Ag-NOR phenotypes were observed among the three populations and confirmed by FISH. Regarding the heterochromatin pattern, H. albopunctatus presented terminal bands and an interstitial block. In H. heraldoi, the heterochromatin was found widely distributed in the terminal and interstitial regions of some st-a chromosomes. In these species, the NORs were also CMA3+/DAPI _. RAPD analysis and sequencing of the cytochrome oxidase subunit I (COI) gene were carried out in these two species, in the Mogi Guaçu population and in three more species, H. regani, H. margaritifer, and H. hermanni, obtaining the same dendrogram pattern. All species could be differentiated by their COI sequences, resulting in a total of 16 haplotypes. These analyses, combined with the morphometric data, showed that H. heraldoi and H. albopunctatus are two valid species and the specimens from the Mogi Guaçu river still retain some characteristics of H. albopunctatus, and were provisionally designated as Hypostomus aff. albopunctatus. Due to the large number of species currently included in the Hypostomus genus, along with both the intra and interspecific variability in morphology and color pattern, there are often problems in the taxonomy of this group, which can be assisted by cytogenetic data. This study provided new chromosomal data for Loricariidae, being a valuable cytotaxonomic tool for the Hypostomini tribe. The joint analysis of different characters, such as cytogenetic, molecular, and morphometric, allowed a more precise characterization of different populations of Hypostomus species, helping to clarify their validity as distinct evolutionary units. Análises citogenéticas convencionais e moleculares foram realizadas em 15 espécies da subfamília Hypostominae, compreendendo 12 espécies da tribo Hypostomini, gênero Hypostomus e três da tribo Ancistrini, gêneros Ancistrus e Hemiancistrus. Foi observado 2n=52 para Ancistrus multispinis (14m+14sm+24st-a), A. brevipinnis (14m+14sm+24st-a) e Hemiancistrus punctulatus (14m+26sm+12st-a). As regiões organizadoras de nucléolos (Ag- RONs) e sítios de DNAr 18S são simples e terminais para as espécies A. brevipinnis, A. multispinis e H. punctulatus. Nestas epécies pode-se constatar que as RONs são também CMA3 +/DAPI-. Quanto à heterocromatina, H. punctulatus apresentou pouca quantidade desse componente cromossômico, enquanto que A. multispinis e A. brevipinnis evidenciaram uma maior quantidade, com grandes blocos no braço longo de alguns pares st-a. Por sua vez, as diferentes espécies de Hypostomus mostraram uma variação de 64 a 82 cromossomos, com diferença na fórmula cariotípica entre as espécies. As RONs foram múltiplas para a maioria das espécies analisadas, sendo observados diferentes fenótipos quanto ao número e posição, o que foi também confirmado pela análise de FISH, evidenciando uma variabilidade interindividual e interespecífica. Em todas as espécies as RONs mostraram-se também CMA3 +/DAPI _. O padrão de distribuição da heterocromatina foi diferente em cada espécie, sendo outro importante marcador cromossômico. Análises citogenéticas, moleculares e de morfometria foram realizadas nas espécies Hypostomus albopunctatus (rio Piracicaba, SP) e H. heraldoi (rio Pirapitinga, GO), assim como em exemplares morfologicamente semelhantes presentes no rio Mogi Guaçu (SP). Todos os indivíduos apresentaram 2n=74, sendo que, H. albopunctatus apresentou 10m+20sm+44st-a e H. heraldoi 8m+20sm+46st-a. As duas fórmulas cariotípicas foram encontradas na população do rio Mogi Guaçu. Fenótipos distintos de Ag-RONs foram observados entre as três populações, confirmadas pela FISH. Quanto ao padrão heterocromático, H. albopunctatus apresentou bandas terminais e um bloco intersticial. Em H. heraldoi, a heterocromatina encontrou-se mais amplamente distribuída, nas regiões terminais e intersticiais de alguns cromossomos st-a. Nessas espécies as RONs mostraram-se também CMA3 +/DAPI _. Análises de RAPD e sequenciamento do gene de Citocromo Oxidase subunidade I (COI) foram realizadas nessas duas espécies, na população do rio Mogi Guacu e em mais três espécies, H. regani, H. margaritifer e H. hermanni, obtendo-se o mesmo padrão de dendrograma. Todas as espécies puderam ser diferenciadas por suas sequências COI, resultando num total de 16 haplótipos. Estas análises, aliadas aos dados de morfometria, evidenciaram que H. heraldoi e H. albopunctatus são duas espécies válidas e que os exemplares do rio Mogi Guaçu ainda conservam algumas características de H. albopunctatus, sendo provisoriamente denominados como Hypostomus aff. albopunctatus. Devido ao elevado número de espécies atualmente incluídas no gênero Hypostomus, juntamente com a variabilidade na morfologia e padrão de coloração tanto intra quanto interespecífica, muitas vezes ocorrem problemas na taxonomia desse grupo, a qual pode ser auxiliada pelos dados citogenéticos. Este estudo forneceu novos dados cromossômicos para os Loricariidae, mostrando-se uma boa ferramenta citotaxonômica para a tribo Hypostomini. A análise conjunta de diferentes caracteres, como citogenéticos, moleculares e morfométricos, possibilitou uma caracterização mais precisa de diferentes populações de espécies de Hypostomus, contribuindo para esclarecer sua validade como unidades evolutivas distintas.

Few chromosomal reports are available for the endemic fish fauna from coastal basins in northeastern Brazil, and regional biodiversity remains partially or completely unknown. This is particularly true for Loricariidae, the most diverse family of armored catfishes. In the present work, allopatric populations of Hypostomus cf. wuchereri (Siluriformes: Loricariidae) from two basins in Bahia (northeastern Brazil) were cytogenetically analyzed. Both populations shared 2n = 76 chromosomes, a karyotype formula of 10m+18sm+48st/a (FN = 104) and single terminal GC-rich NORs on the second metacentric pair. Nevertheless, microstructural differences were detected by C-banding, fluorochrome staining and chromosomal digestion with restriction enzymes (Alu I, Bam HI, Hae III, and Dde I). The population from Una River (Recôncavo Sul basin) showed conspicuous heterochromatin blocks and a remarkable heterogeneity of base composition (presence of interspersed AT/GC-rich and exclusively AT- or GC-rich sites), while the population from Mutum river (Contas River basin) presented interstitial AT-rich C-bands and terminal GC/AT-rich heterochromatin. Each enzyme yielded a specific band profile per population which allowed us characterizing up to five heterochromatin families in each population. Based on the present data, we infer that these populations have been evolving independently, as favored by their geographic isolation, probably representing cryptic species. Poucos dados cromossômicos estão disponíveis para a fauna de peixes endêmicos das bacias costeiras do nordeste do Brasil, e a biodiversidade regional continua a ser parcial ou completamente desconhecida. Isto é particularmente verdadeiro para Loricariidae, a mais diversa família de cascudos. No presente trabalho, populações alopátricas de Hypostomus cf. wuchereri (Siluriformes: Loricariidae) de duas bacias hidrográficas da Bahia (nordeste do Brasil) foram citogeneticamente analisadas. Ambas as populações compartilham 2n = 76 cromossomos, uma fórmula cariotípica de 10m+18sm+48st/a (FN = 104) e um único sinal terminal de RONs GC-ricas no segundo par metacêntrico. No entanto, diferenças microestruturais foram detectados pelo bandeamento C, coloração com fluorocromos e digestão cromossômica com enzimas de restrição (Alu I, BamH I, Hae III e Dde I). A população do rio Una (bacia do Recôncavo Sul) apresentou blocos de heterocromatina conspícuos e grande heterogeneidade de composição de base (presença de sítios AT/GC-ricos intercalados e exclusivamente AT ou GC-ricos), enquanto a população do rio Mutum (bacia do Rio de Contas) apresentou bandas C intersticiais AT-ricas e heterocromatina terminal GC/AT-ricas. Cada enzima gerou um perfil específico de bandas por população que nos permitiu caracterizar até cinco famílias de heterocromatina em cada população. Baseado nos presentes dados, podemos inferir que essas populações têm evoluido de forma independente, favorecidas pelo seu isolamento geográfico, provavelmente representando espécies crípticas.

Cytogenetic analyses were performed on fishes of the genus Hypostomus (Hypostomus ancistroides (Ihering, 1911), Hypostomus strigaticeps (Regan, 1908), Hypostomus regani (Ihering, 1905), and Hypostomus paulinus (Ihering, 1905)) from the seven tributaries of the Paranapanema River Basin (Brazil) by means of different staining techniques (C-, Ag-, CMA3- and DAPI-banding) and fluorescence in situ hybridization (FISH) to detect 18S rDNA sites. All species showed different diploid numbers: 2n=68 (10m+26sm+32st-a) in Hypostomus ancistroides, 2n=72 (10m+16sm+46st-a) in Hypostomus strigaticeps, 2n=72 (10m+18sm+44st-a) in Hypostomus regani and 2n=76 (6m+16sm+54st-a) in Hypostomus paulinus. Ag-staining and FISH revealed various numbers and locations of NORs in the group. NORs were usually located terminally on the subtelocentric/acrocentric chromosomes: on the long arm in Hypostomus strigaticeps (2 to 4) and Hypostomus paulinus (2); and on the short arm in Hypostomus ancistroides (2 to 8) and Hypostomus regani (2 to 4). Conspicuous differences in heterochromatin distribution and composition were found among the species, terminally located in some st-a chromosomes in Hypostomus ancistroides, Hypostomus strigaticeps, and Hypostomus paulinus, and interstitially dispersed in most st-a chromosomes, in Hypostomus regani. The fluorochrome staining indicated that different classes of GC and/or AT-rich repetitive DNA evolved in this group. Our results indicate that chromosomal rearrangements and heterochromatin base-pair composition were significant events during the course of differentiation of this group. These features emerge as an excellent cytotaxonomic marker, providing a better understanding of the evolutionary mechanisms underlying the chromosomal diversity in Hypostomus species.

The complete mitochondrial genome of the armored catfish, Hypostomus plecostomus, was determined by next generation sequencing of genomic DNA without prior sample processing or primer design. Bioinformatics analysis resulted in the entire mitochondrial genome sequence with length of 16,523 bp. The H. plecostomus mitochondrial genome is consisted of 13 protein-coding genes, 22 tRNA genes, 2 rRNA genes, and 1 control region, showing typical circular molecule structure of mitochondrial genome as in other vertebrates. The whole genome base composition was estimated to be 31.8% A, 27.0% T, 14.6% G, and 26.6% C, with A/T bias of 58.8%. This work provided the H. plecostomus mitochondrial genome sequence which should be valuable for species identification, phylogenetic analysis and conservation genetics studies in catfishes.

Seventeen leeches obtained from armoured catfish (Hypostomus punclatus Valenciennes, 1840) infected with Trypanosoma spp. were examined. It was observed the presence of tripomastigotes, epimastigotes and amastigotes forms as well as dividing forms in the proboscis and in the stomach, different from the ones found in the vertebrate host as regards the morfometric features and developing forms. The examination of the contents of rectum did not show tripanosomes. These facts seem to demonstrate that Batracobdella gemmata (Blanchard, 1900) is an invertebrate host of trypanosomes and the transmission is done by means of inoculation.

A new Hypostomus species is described from the rio Cuiabá, upper rio Paraguay basin, Mato Grosso State, Brazil. The new species is distinguished from all other Hypostomus species, with exception of young specimens of H. latifrons, by the presence of a wide dark transverse bars on laterals of body and fins; and conspicuous dark vermiculations on abdominal region. From H. latifrons it differs by having just one pre-dorsal plate surrounding supraoccipital bone and by the maintenance of the dark saddles in adults. Added to the other fish species recently described from the upper rio Paraguay basin, this work helps to highlight that the region still functions as a potential source of new species. Uma espécie nova de Hypostomus é descrita do rio Cuiabá, bacia do alto rio Paraguai, Estado do Mato Grosso, Brasil. A espécie nova é diagnosticada de todas as outras congêneres, com exceção de H. latifrons, pela presença de amplas barras escuras transversais nas laterais do corpo e nadadeiras, e pelas conspícuas vermiculações escuras na região abdominal. De H. latifrons ela difere por ter somente uma placa pré-dorsal margeando o osso supraoccipital e pela manutenção das barras escuras transversais nos adultos. Somada a outras espécies de peixes recentemente descritas na bacia do alto rio Paraguai, este trabalho demonstra que a região ainda funciona como uma fonte potencial de espécies novas.

1. Organophosphorus activation ability of Hypostomus punctatus liver was demonstrated by an in vitro metabolization curve of parathion into paroxon. 2. A calibration curve of paroxon acetylcholinesterase inhibition indicated that about 6.0% of parathion was biotransformed after 2 hr of incubation when the medium contained 0.5 mg of parathion per litre and 0.15 mg of protein. 3. Identification of incubation products by thin layer and gas chromatography showed that paroxon was not the unique resulting product. 4. Microsomal liver activation of parathion was largely dependent on reduction by NADH or NADPH but was only partially inhibited by SKF-525A and CO.

Five species of Siluriformes were registered in the Ubatiba system. Pimelodella lateristriga was the dominant one, followed by Hypostomus gr. punctatus, Rineloricaria sp., Callichthys callichthys and Rhamdia sp. Simple correlation analysis between species density and habitat parameters indicated that hydrology explained density patterns of four species. Pimelodella densities were negatively correlated with pools, Callichthys and Hypostomus densities were positively correlated with runs and Rhamdia densities were positively correlated with riffles; Rineloricaria densities did not respond to any hydrological parameter. Substrata were an important factor to all species, but specific preferences were observed. Marginal vegetation was positively correlated only to Pimelodella densities. Sorensen dissimilarity analysis indicated that site groups, based on both species composition and habitat parameters, were very similar and corroborated the correlation analysis suggesting that Siluriformes composition should be explained by many habitat parameters. Analysis of co-variation of species densities at each sampling occasion showed to be statistically similar in at least all (100%) analysed cases indicating that Siluriformes composition was strongly persistent in time.Cinco espécies de Siluriformes foram registradas no sistema fluvial do rio Ubatiba, Pimelodella lateristriga foi a espécie dominante seguida de Hypostomus gr. punctatus, Rineloricaria sp., Callichthys callichthys e Rhamdia sp. Análises de correlação simples entre as densidades das espécies e as variáveis de hábitat indicaram que a hidrologia explicou os padrões de densidade de quatro espécies; as densidades de Pimelodella foram negativamente correlacionadas com a presença de poças, as densidades de Callichthys e Hypostomus foram positivamente correlacionadas com os rápidos e as densidades de Rhamdia foram positivamente correlacionadas com as corredeiras; as densidades de Rineloricaria não responderam a nenhum dos parâmetros hydrológicos analisados. O substrato foi um importante fator para todas as espécies, mas preferências específicas foram observadas. A vegetação marginal foi positivamente correlacionada apenas com as densidades de Pimelodella. A análise de dissimilaridade de Sorensen indicou que os grupos de localidades que se formaram com base tanto na composição de espécies como nas variáveis de hábitat foram muito semelhantes e corroboraram os resultados das análises de correlação, sugerindo que a composição de Siluriformes do rio Ubatiba pode ser explicada por várias características do hábitat. As análises de co-variância das densidades das espécies em cada momento amostral mostraram-se significativamente similares em todos (100%) os casos analisados, indicando que a composição de Siluriformes é persistente e se mantém em escala temporal.

We sampled fishes within the vertical-slot Igarapava fish ladder (IFL), Grande River, southeastern Brazil, and immediately downstream IFL in 12 field trips from February 2000 to December 2002. A total of 1145 fishes belonging to 13 families and 39 species were captured. The most abundant species captured within the IFL, in order of abundance were: Pimelodus maculatus, Metynnis maculatus, Astyanax altiparanae, Hypostomus spp., Leporinus octofasciatus, Salminus hilarii, Leporinus elongatus, Leporinus friderici, Schizodon nasutus and Prochilodus lineatus. Size distribution of the most abundant fishes captured downstream or within the IFL was similar indicating no constraints to adult fish to ascend the IFL. Except P. maculatus, the number of migratory species captured in the IFL and downstream the IFL were very low. Some of the so-called sedentary species were collected in the IFL indicating that they possess an innate behaviour to migrate. Juveniles of P. lineatus and P. maculatus were captured ascending the IFL implying a dispersal behaviour. Gonadal analyses of the fishes captured in the reproductive season showed that the overall number of reproductive active fishes (which included fish in maturation, mature and spawned/spent) surpassed those non-active. Thus, the IFL offers upstream passage for juveniles, some of the so-called sedentary species, as well as fishes in reproductive migration. Copyright © 2009 John Wiley & Sons, Ltd.

1. A method is presented for measuring respiratory and cardiac rate, as well as microvascular parameters (red blood cell velocity, vessel diameter) in the freshwater catfish Hypostomus cf. punctatus . 2. Unanesthetized animals were kept in a box with flowing water. Microcirculation of the pectoral fin was studied using a closed-circuit television system coupled to a microscope. 3. ECG was recorded with implanted electrodes and respiratory rate was continuously recorded with a cannula close to the mouth. 4. Average values obtained for cardiac, respiratory and cough frequency were 122.8 ± 30.4 min −1 ( n = 4), 105.3 ± 39.4 min −1 ( n = 10) and 90.6 ± 81.1 hour −1 ( n = 6), respectively. 5. The fish usually remained quiet for several hours inside the box while microscopic observations were made.