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Galeocerdo cuvier Peron and Lesueur, 1822 is a tiger shark, a common predatory shark distributed in temperate and tropical countries globally. G. cuvier is also synonymised as G. arcticus (Faber, 1829) and G. rayneri (Mc Donald & Barron, 1868). We report the first observation of one male and one female tiger shark captured by otter trawler at Mudasalodai landing centre, Cuddalore coastal waters, southeast coast of India. Sex was identified by the presence of pair of claspers observed in the ventral side. Male specimen weighed about 1.9 kg and female weighed about 1.65 kg. The morphometric characters of the shark were measured and tabulated. The present study confirmed the occurrence of G. cuvier along the southeast coast of India particularly in the Tamil Nadu coastal waters. [ABSTRACT FROM AUTHOR]

To ensure reproductive success, sharks have adapted several strategies. It was observed that male sharks of Scoliodon laticaudus Müller & Henle, 1838 and Rhizoprionodon acutus (Rüppell, 1837) landed along a few centres of Gujarat coast, have highly calcified claspers which morphologically resembled ossified webbed foot. The morphological and anatomical study revealed that the terminal end of the clasper has been modified into an umbrella like organ called rhipidion which probably ensures that the clasper stays within the cloaca of the female until the sperm is delivered. The landed sharks were all mature. This recent observation of catch of many mature individuals near the coastal waters throws some light on the breeding season and breeding area of sharks along Gujarat coast. With episodes of extinction and threat to the existence of several species of sharks today, this reproductive adaptation of the sharks might helps them to survive and sustain adverse conditions. [ABSTRACT FROM AUTHOR]

Abstract Zearaja chilensis has been reported from Southern Brazil in the Southwest Atlantic (SWA) to northern Chile in the Southeast Pacific (SEP), and it was listed as vulnerable by the IUCN. Recent molecular studies have called into question the conspecificity between specimens from these opposite coasts of South America, which can have implications for the conservation status of the species. To verify the identity of specimens identified as Z. chilensis , 47 individuals from SWA and 22 from SEP were examined. By comparing external morphology, spinulation pattern, clasper, egg cases, and mitochondrial cytochrome c oxidase I (COI) sequence data, differences between groups were found. Adults from SWA presented longer snout length and shorter tail than those from SEP. Dermal denticles were restricted to the rostral area in SWA skates, whereas in SEP skates most of the dorsal surface was covered with denticles. Marked differences in the morphology of several components of clasper were noticeable. Egg cases of SWA skates had thinner lateral keels than those of SEP. Molecular analysis revealed two well-defined cohesive clusters, corresponding to SWA and SEP specimens, respectively. Average K2P distance between groups was 3.4%, higher than expected for intraspecific differences, and sequences were assigned to different BINs. These integrative approaches strongly support that specimens from SWA known as Z. chilensis correspond to a different nominal species than those from SEP. Herein, Z. brevicaudata (Marini 1933) is resurrected from synonymy with Z. chilensi s. [ABSTRACT FROM AUTHOR]

Abstract: Females in many animal species must discriminate between conspecific and heterospecific males when choosing mates. Such mating preferences that discriminate against heterospecifics may inadvertently also affect the mating success of conspecific males, particularly those with more extreme phenotypes. From this expectation, we hypothesized that female mate choice should cause Enallagma females (Odonata: Coenagrionidae) to discriminate against conspecific males with more extreme phenotypes of the claspers males use to grasp females while mating – the main feature of species mate recognition in these species. To test this, we compared cerci sizes and shapes between males that were captured while mating with females to males that were captured at the same time but not mating in three Enallagma species. In contrast to our hypothesis, we found only one of forty comparisons of shape variation that was consistent with females discriminating against males with more extreme cerci shapes. Instead, differences in cerci shape between mating and single males suggested that females displayed directional preferences on 1–4 aspects of cerci shape in two of the species in our samples. These results suggest that whereas some directional biases in mating based on cerci shape occur, the intraspecific phenotypic variation in male cerci size and shape is likely not large enough for females to express any significant incidental discrimination among conspecifics with more extreme shapes. [ABSTRACT FROM AUTHOR]

Documented cases of abnormalities in elasmobranchs worldwide are more often reported for sharks than their close relatives, the skates and rays. This report confirms the occurrence of a chola guitarfish, Pseudobatos percellens (Walbaum, 1792), caught off Margarita Island, Venezuela, showing morphological abnormalities on the right side of the body, including the absence of one clasper. This is the first record of an anomalous singleclasper case in the Caribbean Sea region. [ABSTRACT FROM AUTHOR]

Background: Batoids exhibit unique body plans with derived fin morphologies, such as the anteriorly expanded pectoral fins that fuse to the head, or distally extended anterior pelvic fin lobes used for a modified swimming technique utilized by skates (Rajidae). The little skate (Leucoraja erinacea), exhibits both of these unique fin morphologies. These fin modifications are not present in a typical shark body plan, and little is known regarding the mechanisms underlying their development. A recent study identified a novel apical ectodermal ridge (AER) associated with the development of the anterior pectoral fin in the little skate, but the role of the posterior HoxA genes was not featured during skate fin development. Results: We present the first evidence for HoxA expression (HoxA11 and HoxA13) in novel AER domains associated with the development of three novel fin morphologies in a representative batoid, L. erinacea. We found HoxA13 expression associated with the recently described novel AER in the anterior pectoral fin, and HoxA11 expression in a novel AER domain in the anterior pelvic fin that we describe here. We find that both HoxA11 and HoxA13 are expressed in claspers, and while HoxA11 is expressed in pelvic fins and claspers, HoxA13 is expressed exclusively in developing claspers of males. Finally, HoxA11 expression is associated with the developing fin rays in paired fins. Conclusion: Overall, these results indicate that the posterior HoxA genes play an important role in the morphological evolution of paired fins in a representative batoid. These data suggest that the batoids utilize a unique Hox code, where the posterior HoxA genes exhibit distinct expression patterns that are likely associated with specification of novel fin morphologies. [ABSTRACT FROM AUTHOR]

This study presents information on the reproductive biology of Psammobatis rutrum based on 55 males and 53 females obtained as by-catch from bottom trawlers off southern Brazil during July 2013 and September 2014 and includes a detailed description of the egg capsule. Total lengths ( LT) ranged from 22·3 to 31·6 cm and most of the sample comprised larger individuals, although there were no sexual differences in length-frequency distributions. Significant sexual differences were found for total length-disc width, LT-body mass and LT-eviscerated body mass relationships, with females being heavier and larger. Males started to mature at 25·5 cm LT and females, at 25·9 cm LT, while LT at maturity was calculated in 26·67 and 26·81 cm, respectively. Attaining larger sizes and mass may represent a reproductive investment for females, as observed in other rajoid species. Egg bearing females were first observed over 27·1 cm LT and ovarian fecundity was 1-12 vitellogenic follicles. The egg capsules were 2·22-2·62 cm length and had attaching fibrils on both lateral sides. Microscopically, the ventral face of the egg capsule was rougher than the dorsal face. [ABSTRACT FROM AUTHOR]

The family Rhinochimaeridae, the long-nose chimaerids, consists of eight species across three genera, two of which occur in New Zealand waters. Very little is known about the biology of the rhinochimaerids. Longnose spookfish, ( Harriotta raleighana , Goode and Bean, 1895 ), and Pacific spookfish, ( Rhinochimaera pacifica, Mitsukuri, 1895 ), were collected from research trawl surveys and by commercial fishing vessels around New Zealand at depths between 400 and 1300 m. A total of 300 H. raleighana were caught which varied in length from 18.7 to 90.4 cm chimaera length (CL), and 168 R. pacifica at lengths of 20.9–139.9 cm CL. External assessment of male claspers and female gonad mass and oviducal gland width were the best indicators for maturity. Both species matured at a large proportion of their maximum length. Length at maturity was estimated at 62.8 cm CL and 75.8 cm CL for male and female H. raleighana respectively, and 105.3 cm CL and 125.0 cm CL for male and female R. pacifica . Fecundity was low and measured up to 27 eggs for H. raleighana, and 31 eggs for R. pacifica . Sperm storage was confirmed in females of both species. Sexual dimorphism in snout length was found in H. raleighana , where male relative snout size increased at sexual maturity, suggesting the snout is a secondary sexual characteristic. This study contributes to a better understanding of the life histories of H. raleighana and R. pacifica and their vulnerability to exploitation as fisheries bycatch. [ABSTRACT FROM AUTHOR]

In animals with internal fertilization, male genitalia exhibit higher rates of divergence compared with other morphological trails. Recent evidence suggests sexual selection drives such as rapid and divergent trait evolution. External male genital structures which clasp or stimulate the female's exterior are likely to be under similar selective constraints to internal genitalia; however, their function and influence on male mating success have rarely been studied in detail. Here, we modify the external genitalia of the phasmid Clitarchus hookeri (White) to assess the role of male claspers in achieving successful acceptance by females and subsequent copulation. By covering female opercular organs and abrading male claspers, we demonstrate the necessity of precise coupling between these external genitalic structures for copulation to take place. We found that modified females tolerate un-modified male clasping attempts up to four times longer than normally required for attachment. However, when un-modified females are contacted by modified male claspers, males are quickly rejected. Our results suggest that external genital structures play an important role in precopulatory mate acceptance. Here, we discuss the potential role of female choice and species, isolating hypotheses in explaining the high evolutionary rate of such structures. Significance statement: Many male animals possess genital structures that allow them to grip on to females before, during, and after mating. We experimentally manipulated male claspers and the corresponding female morphology that is clasped by males for the stick insect Clitarchus hookeri, resulting in clear changes in mating behavior. We show that female mate acceptance is influenced by both the structure of male claspers and the ability of females to perceive clasping. This demonstrates that external genital structures can play an important role in precopulatory mate acceptance and that female choice is likely to influence their evolution. [ABSTRACT FROM AUTHOR]

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Laevicaudatan clam shrimps have been previously reported from Thailand, but were only tentatively identified. We report on two new species of laevicaudatan clam shrimps from Thailand collected after conducting widespread, intensive surveys across the central region of the country. We present diagnoses for each, with remarks on the Asian taxa. Lynceus spinimanus n. sp. is separated from all congeners by the form of the male claspers, the female rostral morphology, and the unique chitinized and projecting epipod and exopod on the female thoracopod XI. Lynceus planifascius n. sp. is separated from all congeners by the form of the rostrum in both sexes and the form of the male clasper. An identification key to the currently accepted Eurasian Lynceus species is provided. [ABSTRACT FROM AUTHOR]

In this study, two parthenogenetic events within a family of the whitespotted bambooshark Chiloscyllium plagiosum are reported. A captive female produced multiple parthenogens. Unexpectedly, a single specimen of a total of nine parthenogens displayed external claspers characterizing the male sex in chondrichthyans. Upon dissection, internal sexual organs of this specimen were malformed or absent; however, the presence of claspers in this study challenges the as yet assumed sex determination system in this shark species. Even more remarkable was that one of the female parthenogens reproduced asexually again producing viable offspring. As far as is known, this is the first genetically confirmed evidence for second-generation facultative parthenogenesis in vertebrates. These results support the evolutionary significance of parthenogenesis as an alternative to sexual reproduction. [ABSTRACT FROM AUTHOR]

A new species of Lachesilla, from the Mexican state of Chiapas, is described and illustrated, it is assigned to species group Corona on basis of the paraprocts, epiproct, and phallosome apodemes; the hypandrium and claspers do not seem to fit well into species group Corona. [ABSTRACT FROM AUTHOR]

ABSTRACT Newly discovered pelvic and reproductive structures within placoderms, representing some of the most crownward members of the gnathostome stem group and the most basal jawed vertebrates, challenge established ideas on the origin of the pelvic girdle and reproductive complexity. Here we critically review previous descriptions of the pelvic structures in placoderms and reinterpret the morphology of the pelvic region within the arthrodires and ptyctodonts, in particular the position of the pelvic fin and the relationship of the male clasper to the pelvic girdle. Absence of clear articular surfaces on the clasper and girdle in the Arthrodira, along with evidence from the Ptyctodontida, suggest that these are separate structures along the body. We describe similarities between the pectoral and pelvic girdles and claspers, for example, all these have both dermal and perichondral (cartilaginous) components. Claspers in placoderms and chondrichthyans develop in very different ways; in sharks, claspers develop from the pelvic fin while the claspers in placoderms develop separately, suggesting that their independent development involved a posterior extension of the 'competent stripes' for fin development previously limited to the region between the paired pectoral and pelvic fins. Within this expanded zone, we suggest that clasper position relative to the pelvic fins was determined by genes responsible for limb position. Information on early gnathostome reproductive processes is preserved in both the Ptyctodontida and Arthrodira, including the presence of multiple embryos in pregnant females, embryos of differing sizes and of different sexes (e.g. male claspers preserved in some embyros). By comparison with chondrichthyans, these observations suggest more complex reproductive strategies in placoderms than previously appreciated. [ABSTRACT FROM AUTHOR]

Australia has a far greater diversity of Eulimnadia than previously reported. Eulimnadia feriensis has been rediscovered and redescribed. It is unusual in having a spiniform ventroposterior projection on the telson and a spiny clasper. Three new species of Eulimnadia are also presented, each with atypical claspers and complex egg morphology. All four species occur mainly in southern Western Australia, a known hotspot for branchiopod diversification associated with long term climate change. [ABSTRACT FROM AUTHOR]

ABSTRACT Male 'clam shrimps' possess highly modified first (and second) trunk limbs for clasping the carapace of females during copulation. Claspers are present in all three clam shrimp taxa (Laevicaudata, Spinicaudata, and Cyclestherida) but despite striking similarities in their morphology and function, the matter of their homology is controversial. In this study, we address the question of the homology and evolution of these structures by comparing the developmental transformation of an unspecialized trunk limb into a clasper. In addition, we study the musculature and the nervous system in trunk limbs and claspers using confocal laser scanning microscopy. We establish that most (but not all) of the various parts of the claspers are homologous between clam shrimp taxa. We suggest that a single pair of claspers was already present in the ground pattern of Diplostraca, probably most comparable to those in Cyclestherida. The claspers, therefore, do not represent a case of analogy. J. Exp. Zool. (Mol. Dev. Evol.) 322B: 269-280, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

A large collection of earwigflies, Merope tuber, is reported from Arkansas, and flight period and sex ratio are discussed. In contrast to previous studies, earwigflies were caught more frequently in pan traps than in Malaise traps and male clasper size was found not to be bimodal. [ABSTRACT FROM AUTHOR]

Clam shrimps are freshwater branchiopod crustaceans which often present complicated breeding systems including asexual reproduction (parthenogenesis) and mixed mating systems (in androdioecious species both selfing and outcrossing occurs due to the co-presence of hermaphrodites and males). Reproductive patterns of Spinicaudata, which contains most clam shrimp species, have received much attention. Another group of clam shrimps, Laevicaudata, which holds a key position in branchiopod phylogeny, has practically not been studied. As a part of the mating process, males clasp to the carapace margin of the females with a pair (or two pairs) of anterior trunk limbs modified as claspers. Previous studies have shown that clasper morphology is important in a phylogenetic context, and that some parts of the claspers in Spinicaudata and Laevicaudata may have undergone a remarkable parallel evolution. Here we have used video microscopy to study aspects of the mating behaviour, egg extrusion, and fertilization in Lynceus brachyurus (Laevicaudata). It is shown that fertilization is likely to be external and that the peculiar tri-lobed lateral lamellae of female's hind body assist in guiding the egg mass to the exopodal egg carriers where they are collected by their distal setation. The functional morphology of the male claspers was studied in detail by close-up video recordings. The movable “finger” of the clasper bends around the female's carapace edge and serves to hold the female during mating. The larger palp grasps around the female carapace margin in a way very similar to the movable “finger”, possibly indirectly providing sensory input on the “finger” position. A brief comparative study of the claspers of a spinicaudatan clam shrimp showed both similarities and differences to the laevicaudatan claspers. The presence of two pairs of claspers in Spinicaudata seems to give males a better hold of the female which may play a role during extended mate guarding. [ABSTRACT FROM AUTHOR]

A novel statistical method for estimating the stages of maturity in male sharks and skates based on a segmented regression (SRM) is proposed. We hypothesize that this method is able to find the transition points in the three-phase relationship between total length (TL) and clasper length (CL). We applied an SRM to TL-CL data of nine species, from large pelagic sharks (e.g., Carcharhinus falciformis) to small coastal skates (e.g., Rioraja agassizi), captured in the southwestern Atlantic and northeastern Pacific. As expected, SRM detected two breakpoints, defining three maturity stages (immature, maturing, and mature), in six out of nine species. For three species, it was not possible to find two breakpoints because of incomplete sampling of TL. This novel method is noninvasive, it is applicable to previously collected data, is easy to use, and provides a reliable tool for increasing our understanding of elasmobranch reproductive strategies. [ABSTRACT FROM AUTHOR]

Abstract: Detailed structure of the male genitalia of Anevrina is described. Hitherto unknown morphological characters of the internal sclerites relating to the epandrium and hypandrium are illustrated and elucidated. The subepandrial sclerite + bacilliform sclerites are distinctly modified, and the typical subepandrial sclerite is not recognizable. The right base of the medially shifted right surstylus is not connected to the posterior margin of the epandrium, and is directly supported by a robust bacilliform sclerite. The robust bacilliform sclerites are greatly developed inside the epandrium, and extended to three clasping components, the left surstylus, the medially shifted right surstylus and a pair of clasping lobes on the posteroventral margin of the right side of the epandrium. The upper lobe of a pair of clasping lobes on the right side of the epandrium is considered to originally have been situated on the left side and subsequently shifted to the right side. The plesiomorphic state of the clasping components relative to Anevrina is thought to be symmetrically four, comprising both the left and right surstyli and the posterior edge of both sides of the epandrium, indicating that the amazing phenomenon of cross-shifting of the clasping components has occurred in Anevrina. A cladogram generated based on the genitalic characters observed in this study shows sister groups within Anevrina, namely an Anevrina urbana-group comprised of A. urbana, A. setigera, A. olympiae, A. variabilis, A. thoracica, and an Anevrina unispinosa-group comprised of A. unispinosa, A. curvinervis, A. luggeri and A. macateei. [Copyright &y& Elsevier]

Lepeophtheirus acutus (Caligidae, Siphonostomatoida, Copepoda), was collected from or observed on four of six elasmobranch species held at Burgers' Zoo (Arnhem, The Netherlands). Circumstantial evidence suggested that a zebra shark, Stegostoma fasciatum (Hermann), from the wild carried the infection into the facility, where copepods reproduced and colonized additional hosts. Copepods typically attached on and about the eyes, in the mouth and occasionally about the cloaca and on the claspers. Severe ocular lesions were associated with infections on zebra sharks, a grey reef shark, Carcharhinus amblyrhynchos (Bleeker), whitetip reef sharks, Triaenodon obesus (Rüppell), and giant shovelnose ray, Rhinobatos typus Bennett, while blacktip reef sharks, Carcharhinus melanopterus (Quoy & Gaimard), and blacktip sharks, Carcharhinus limbatus (Valenciennes), living in infested aquaria showed no sign of infection. Water treatments using trichlorfon were considered primarily responsible for the eradication of copepods from hosts and infested aquaria. This case is the first report of a copepod infection being closely associated with disease and death of an aquarium-held elasmobranch. Given its ability to infect a wide variety of elasmobranchs and promote life-threatening lesions on some hosts, L. acutus should be considered a dangerous pathogen of captive elasmobranchs. [ABSTRACT FROM AUTHOR]

The guitar ray Rhinobatos leucorhynchus is commonly caught as by-catch of industrial and artisanal shrimp trawling in the shallow waters of the Colombian Pacific. The biological aspects of this species were studied using 286 animals caught as by-catch between 2001 and 2007. The females were proportionally larger than males, although growth was similar (allometric) for both sexes. The embryos showed no significant differences by sex in either size or weight. The adult sex ratio was 2.4:1 (females-males), whereas in embryos this ratio was 1:1. 51.5% of males, 51.5% had developed, calcified claspers, and 56.5% of females were pregnant, carrying between 1 and 6 embryos of 3 to 19.5 cm, suggesting a size at birth of 19 to 19.5 cm TL. The median size at maturity for females was lower than that of males (48.48 cm and 51.18 cm TL, respectively), and the females had embryos starting at 44 cm TL. The feeding habits of this species showed 30 prey items, with shrimp from the Penaeidae family and especially Trachypenaeus sp. as main food. The diets of male and female guitar rays differed significantly, and the niche breadth indicated that this species has a specialist diet. The results of this study provide useful information for proposing management measures for R. leucorhynchus, a species that requires attention given its biological characteristics and its importance in terms of commerce and human consumption. [ABSTRACT FROM AUTHOR]

Let S be a compact connected oriented surface whose boundary is connected or empty. A homology cylinder over the surface S is a cobordism between S and itself, homologically equivalent to the cylinder over S. The Y-filtration on the monoid of homology cylinders over S is defined by clasper surgery. Using a functorial extension of the Le–Murakami–Ohtsuki invariant, we show that the graded Lie algebra associated to the Y-filtration is isomorphic to the Lie algebra of ‘symplectic Jacobi diagrams’. This Lie algebra consists of the primitive elements of a certain Hopf algebra whose multiplication is a diagrammatic analogue of the Moyal–Weyl product. The mapping cylinder construction embeds the Torelli group into the monoid of homology cylinders, sending the lower central series to the Y-filtration. We give a combinatorial description of the graded Lie algebra map induced by this embedding, by connecting Hain’s infinitesimal presentation of the Torelli group to the Lie algebra of symplectic Jacobi diagrams. This Lie algebra map is shown to be injective in degree 2, and the question of the injectivity in higher degrees is discussed. [ABSTRACT FROM PUBLISHER]

A new cicada species, Dilobopyga aprina Lee, sp. nov. from Sulawesi is described. This new species is distinguishable from its congeners by the presence of 2 pairs of transverse black spots on the abdominal tergite 3 and the absence of such spots on other tergites and by the unique shape of the upper lobes of pygofer and the long and pointed claspers in the male genitalia. [ABSTRACT FROM AUTHOR]

Male structures for clasping females during precopula interactions and mating (“claspers”) have evolved in many groups of arthropods. Several hypotheses regarding the function of claspers have been proposed. We describe how males of the true bug Stenomacra marginella (Heteroptera: Largidae) move their genital claspers during sexual interactions, and present the results of experiments in which we tested whether claspers are necessary to achieve intromission. When one and both claspers were partially amputated, the probability of successful intromission decreased from 62 to 0% and from 57 to 3%, respectively. Behavioral observations indicate that the claspers open the valves that cover the female genital opening. We consider the possibility that claspers in S. marginella may have multiple functions. [ABSTRACT FROM AUTHOR]

Habiro found in his thesis a topological interpretation of finite type invariants of knots in terms of local moves called Habiro's Ck-moves. Ck-moves are defined by using his claspers. In this paper we define "oriented" claspers and RCk-moves among ribbon 2-knots as modifications of Habiro's notions to give a similar interpretation of Habiro–Kanenobu–Shima's finite type invariants of ribbon 2-knots. It works also for ribbon 1-knots. Furthermore, by using oriented claspers for ribbon 1-knots, we can prove Habiro–Shima's conjecture in the case of ℚ-valued invariants, saying that ℚ-valued Habiro–Kanenobu–Shima finite type invariant and ℚ-valued Vassiliev–Goussarov finite type invariant are the same thing. [ABSTRACT FROM AUTHOR]

Since 1855, 28 species of clam shrimps (Laevicaudata, Spinicaudata, Cyclestherida) have been described from Australia, although three have been synonymized. One new species of Eocyzicus is described herein. It has a distinctive rostrum that is slightly different in male and females and the clasper has a three segmented palp. With this new species the Australian fauna comprises 26 valid species of clam shrimps. We provide a list of all described species, including their known localities and a key to the genera of Australian clam shrimps. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To investigate whether detrusor overactivity (DO) and the response to the ice water test (IWT) influence nighttime urinary frequency in patients with lower urinary tract symptoms. Methods: A total of 114 patients with lower urinary tract symptoms, who were older than 50 years, with an International Prostate Symptom Score 8 or more points and a quality of life index of 2 or greater, were evaluated by a 48-hour frequency-volume chart, free flowmetry, pressure flow study, and IWT. Results: The DO-positive IWT responders had a significantly greater bladder outlet obstruction index than did the DO-positive IWT nonresponders and the DO-negative IWT nonresponders. The DO-positive IWT responders had significantly more frequent nocturia and smaller nighttime maximal and minimal voided volumes than did the DO-negative IWT nonresponders without any difference in the nocturnal voided volume. The patients with nocturia two or more times had a significantly larger nocturnal voided volume and smaller nighttime minimal voided volume than the patients with nocturia less than two times. The incidence of DO-positive IWT responders was significantly greater among the patients with nocturia three or more times than that among those with nocturia less than three times. In the multivariate logistic model, the nocturnal voided volume and nighttime minimal voided volume were independently associated with nocturia two or more times and the DO-positive IWT responders were independently associated with nocturia three or more times. Conclusions: Once high-grade bladder outlet obstruction induces C-fiber-related DO, it is strongly suggested that this process, together with nocturnal polyuria, plays an important role in the consequent clinical manifestations of nocturia in patients with lower urinary tract symptoms. [Copyright &y& Elsevier]

The total lengths ( LT) at which 50% were mature of Psammobatis rudis and Psammobatis normani, in the south-west Atlantic were: P. rudis, 428 mm for males and 414 mm for females and P. normani, 443 mm for males and 403 mm for females. Clasper length in mature males was greater in P. normani than in P. rudis, whereas oviducal gland width was not different between species. Females of P. normani with egg cases were found in every month sampled, and in January, March, April and July in P. rudis, although insufficient samples were available to identify peak oviposition times. Geographic variation in size frequency and maturity were found. The effects of oceanographic conditions and fishing pressure are discussed. Size at 50% maturity in both species was >74% of the maximum LT, indicating late sexual maturity and low potential stock recovery rate. [ABSTRACT FROM AUTHOR]

A new species of softnose skate, Bathyraja cousseauae, is described from two adult and 19 juvenile specimens collected from different localities of the southwestern Atlantic. Bathyraja cousseauae is distinguished from all other southwestern Atlantic softnose skate species by its color pattern, squamation pattern of dorsal surface, lack of interspace between dorsal fins, and clasper morphology. The new species has a round pale area ocellus-like, margined with dark brown on posterior part of each pectoral base of dorsal surface, paler and dark spots over the disk, a continuous row of 21-27 median thorns from nuchal region to first dorsal fin and upper side of disc densely covered with dermal denticles. Males have rod-shaped claspers not expanded at proximal section of glans as it does in Bathyraja brachyurops. Besides the external morphological features, skeletal characteristics (neurocranium, scapulocoracoids, and claspers) are also described and illustrated here. [ABSTRACT FROM AUTHOR]

Logistical ogives gave an estimated LT50 value (i.e. the total length at which 50% individuals are sexually mature) of 635 mm for female and 650 mm for male Sympterygia bonapartii. Mature individuals of both sexes had significantly larger livers than immature ones and females had a significantly heavier liver than males. Clasper elongation was the first step in male maturation, followed by clasper calcification and the development of alar thorns. In mature females, the right ovary was larger than the left, which was apparently due to differences in stroma tissue. Gonadosomatic index and diameter of ovarian follicles of mature females peaked in late spring and was at a minimum from late summer and through the winter. Juvenile S. bonapartii were more abundant near estuarine areas during winter, and adults appeared in estuaries by late spring and summer. Females carrying egg-cases were found near the shore in late spring and egg-cases were found in benthic samples only in shallow waters suggesting that S. bonapartii deposits egg-cases in shallow waters during late spring-summer and that nursery areas are in outer estuarine zones. In the southern part (38°–42° S) of the study area S. bonapartii showed a strong movement to shallow waters in late spring and summer, spreading over the entire coastal area in winter. These movements are discussed in relation to water temperature and trophic interactions. Copyright 2002 The Fisheries Society of the British Isles. Published by Elsevier Science Ltd. All rights reserved. [Copyright &y& Elsevier]