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Oxychilus (Drouetia) viridescens n.sp. Helix atlantica Morelet & Drouët, 1857: 149 (partim); Morelet, 1860: 167 (partim). Types. Holotype (Figs. 2 A, 4 A, C; Table 2, Ov 1): Natural History Museum, London (NHMUK 20100658). Paratypes: Natural History Museum, London (2 specimens NHMUK 20100659); Muséum National d’Histoire Naturelle, Paris (1 specimen MNHN 24265); National Museum of Natural History, Washington (2 specimens USNM 1155712 and 1155713); Museum of Comparative Zoology, Harvard University, Cambridge (1 specimen MCZ 373862); Royal Belgian Institute of Natural Sciences, Brussels (1 specimen IG 31765 (MT 2329); Museum of Natural History, Wroclaw University, Poland (1 specimen MP 1011); Department of Biology, University of the Azores, Portugal (7 specimens DB/UAç-MT 1423 and 1424). Type locality. Ribeira Funda, Feteiras de Santa Bárbara, Santa Maria, Açores (N 36 º 59 ’ 57 ”, W 25 º 05’ 03”) (Figure 1 and Table 1, Sta 1) Etymology. The name refers to the characteristic greenish color of the shell. Diagnosis. Shell diameter 8 mm, greenish, umbilical region grayish, columellar lip and parietal lip almost at the same plane; penis very thin, penial caecum long; epiphallus with two distinct swellings, proximal one attached to penial sheath, distal one attached to penial constriction; distal vagina glandular. Description. Shell (Figs. 2, 3, 4 C; Table 2) up to 8.2 mm in diameter and 4.8 mm in height, non-umbilicate, somewhat solid, translucent, glossy, conspicuously golden green, with very fine, microscopic spiral striae crossing dense and regular growth lines; spire low, with up to 6.2 flattened whorls, last whorl with a squarish profile. Aperture oblique, the columellar lip running almost at the same plane as the parietal lip (see Fig. 4 C); outer lip sharp, columellar lip slightly reflected over the umbilical region which is grayish and covered by a tenuous, whitish callus. Protoconch not well defined, with very faint, fine spiral striae continuing more markedly on the teleoconch. Animal (Fig. 4): neck blue with purplish hues changing gradually to light orange toward the foot, the darkly pigmented posterior tentacle retractors conspicuous through the dorsal neck skin; four dorsal white grooves run forward from the border of the mantle on the dorsal neck, the central ones to the posterior tentacles and front, the two lateral ones descending obliquely, on each side, to underneath the anterior tentacles; head and front with dark blue longitudinal streaks on a pinkish background; posterior tentacles long, dark grayish blue, clearer near base, anterior tentacles faintly blue with sparse brownish dots near the tips; posterior dorsal tip of foot dark blue; sole of the foot longitudinally tripartite, whitish green to dark yellow. Mantle collar (Figs. 4, 5) dark blue, darker around the pneumostome and lappet, becoming lighter toward the left side of the animal. The three basic lobes of the mantle border (secretory, sensory and muscular) are present and are here referred to as rings, the term “lobe” being reserved to follow the current terminology for the description of this structure in helicids (e.g., Martins 2002). Outer, secretory ring, responsible for the secretion of the shell, thin, somewhat retracted behind the next ring, surrounding the entire border of the mantle. The middle, thick, originally sensory ring is bilobed and appears to be primarily of a glandular nature as indicated by its spongy appearance, and it is separated on its right side by the deep pneumostomal slit; right lateral lobe triangular, gently narrowing posteriorly from the lappet; right dorsal lobe forming the dorsal tip of the lappet and extending continuously outside the innermost, left dorsal lobe. Inner, muscular ring expanding to each side of the pneumostome in two wide and thin flaps, the subpneumostomal lobe and the left lateral lobe. The three rings compress posteriorly into a narrow, rounded canal. The blotched coloration of the visceral mass is seen through the translucent, greenish shell; conspicuous dark spot just behind the pneumostomal area, the remaining few spots, of various sizes, yellowish, sparsely distributed over a brownish green to golden green background. Pallial cavity (Fig. 6) elongated, deep; kidney bilobed, completely located in the pallial cavity, roughly triangular, with narrow and elongate anterior lobe squeezed between the heart and the primary ureter; sigmurethrous, secondary ureter bordering posterior lobe of kidney, then bending anteriorly as it approaches the rectum and following forward to open in a cloacal atrium, side-by-side with the rectum, near the pneumostome; a valve-like papilla, the pneumostomal valve, isolates the cloacal atrium from the pneumostomal aperture, thus separating the excretory slit from the pneumostomal canal. A thick, glandular body lies between the secondary ureter and the rectum, to the right of the kidney. Various white, possibly calcareous bodies aggregate in blotches irregularly dispersed throughout the roof of the pallial cavity. Mandible (Fig. 7) oxygnathous, moderately long, strong, smooth, half-moon shaped, with convex median prominence on its free edge. Radula (Fig. 8) [21 +(1 + 2)+ 1 +(2 + 1)+ 21]× 50. Central tooth shorter and narrower than laterals, tricuspid; mesocone long, about half the length of the tooth, narrow, sharply pointed; ectocones small, sharp; base narrowing towards the crown, base line receding medially until at about the tip of the mesocone. First lateral tooth about twice as long as the central, tricuspid, endocone moderately long and merging medially into a basal tooth, receding laterally along with the base, with which it forms a pointed, long mesocone, the tip of which extends up to the arms of the base of the central tooth, ectocone short, triangular, wide, located far back in the crown; second lateral tooth similar to the first, but larger; a third lateral tooth of the transitional (intermediate) type is also tricuspid but much narrower than the other two, the shape resembling a marginal tooth, with both endocone and ectocone very small, sharp, mesocone long, curved and pointed. Marginal teeth falciform, retaining only the mesocone which is long, curved and pointed; first marginal teeth about the size of the transitional tooth, decreasing in size towards the outer edge of the row. Reproductive system (Figs. 9–11). Ovotestis acinose, four acini embedded in last whorls of posterior lobe of digestive gland; hermaphroditic duct long, with a median convoluted seminal vesicle, connecting to base of albumen gland through a small, pouch-like fertilization chamber; spermoviduct morphologically divided into three portions: (1) a proximal whitish, globular, glandular portion into which the fertilization chamber opens distally, (2) a narrow, weakly convoluted channel, and (3) a wide, strongly convoluted and internally folded portion to which the elongate prostate gland adheres; after the separation of the prostate duct into a vas deferens, a free oviduct funnels into the confluence with the bursa duct, both ducts opening into a wider vagina, the extremities of the three ducts covered with a spongy perivaginal gland; vagina adhering to neck wall, the proximal half muscular, smooth outside and ridged inside, the distal portion spongy, apparently glandular, opening into a small, internally smooth genital atrium. Penis almost entirely covered with a thick penial sheath, long and very thin, divided by a constriction into two equally long chambers, with a conspicuous penial caecum proximally, and the distal half internally ridged with pilasters; epiphallus at least twice as thick as the penis where it inserts laterally through a narrow duct; the epiphallus is composed of two distinct long swellings, the proximal portion attached by muscular strands to the edge of the penial sheath (primary epiphallic attachment), the distal portion attached to the penial constriction (secondary epiphallic attachment), thus causing the distal swelling to be almost entirely wrapped by the penial sheath; penial retractor muscle long and thin, inserting on back of the mantle cavity, near the heart region. Spermatophore (Fig. 12) moderately long, thin, anterior portion hooked, with four high, longitudinal ridges, remainder of spermatophore laterally flattened. Nervous system (Fig. 13) of the zonitoid type (Bargmann 1930), the cerebral ganglia large, pleural ganglia triangular, left parietal ganglion conspicuous, distinct from visceral ganglion which is fused to right parietal ganglion; right cerebropleural connective very short causing the visceral nerve ring to be lopsided to the right; pedal ganglia nearly fused, slightly smaller than the cerebral ganglia. Right tentacular nerve crossing between male and female organs; penial nerve branching off the right internal lip nerve. Habitat. Like most consubgenerics, Oxychilus (Drouetia) viridescens lives in shady, moist environments of primary forests, and of secondary forests of Pittosporum, Acacia or Cryptomeria with undergrowth of Tradescantia, preferentially gathering under piles of rocks, fallen logs and dead leaves of Hedychium. Distribution. The new species is distributed throughout the mountainous region of the island of Santa Maria. Although not common, it was most abundantly collected at the type locality, near Santa Bárbara, and also on the northern and western slopes of Pico Alto. Remarks. In their first publication, Morelet & Drouët (1857) described most of the new records from their expedition to the Azores without precise locality data. Subsequently, Morelet (1860) provided these data while Drouët (1861) further completed them with his own notes. Morelet (1860) vaguely stated that Helix atlantica lived in most Azorean islands but, apparently, the species description was based on material from São Miguel, for Morelet (1860: 168–169) remarked that it was abundant mainly in this island, while referring to peculiar varieties in Santa Maria and Faial. However, no type locality was assigned to the species. Morelet's (1860) variety “γ var. spectabilis ” from Santa Maria was elevated to specific rank by Milne-Edwards (1885) (Fig. 14), and Riedel (1964) awarded subspecific rank to Morelet's (1860) “β minor ” from Faial and described Oxychilus atlanticus brincki from material collected in 1957 by the Lund expedition from which he selected a holotype (Fig. 15 A). Riedel (1964) also restricted the type locality of Helix atlantica to the island of São Miguel. Later Riedel (1980) raised the taxa from Santa Maria and Faial to species level. However, three specimens from Santa Maria are marked as syntypes of H. atlantica in the Natural History Museum, London; two of them belong in fact to the new species herein described, the other being Riedel’s (1964) O. (D.) brincki. Hence, due to Riedel’s (1964) taxonomic decisions, the type material for the name Helix atlantica is from a locality where this species does not occur. Therefore, a petition was submitted to the ICZN (Case 3553; Martins et al. 2011) to render those specimens unavailable for nomenclatural purposes. However, the recent discovery of Henri Drouët’s collection and syntypes at the Muséum Jardin des Sciences de Dijon (MJSD) (Cédric Audibert, in litt.), has allowed us to select a lectotype of H. atlantica from São Miguel island, thereby rectifying the anomalous situation created by Riedel (1964). The imperforate Oxychilus are represented in the Açores by two endemic subgenera: Drouetia, present throughout the archipelago, and the monotypic Atlantoxychilus Riedel, 1964, only recorded from Santa Maria [O. (A.) spectabilis (Milne-Edwards, 1885)]. Three species of Drouetia live in Santa Maria: Oxychilus (D.) brincki, O. (D.) agostinhoi Martins, 1981 and O. (D.) viridescens n.sp (Figs. 15, 16). Oxychilus (D.) viridescens and O. (D.) brincki are conchologically similar but can be readily distinguished from Oxychilus (D.) agostinhoi, which has a very small, paucispiral, flat shell and from O. (A.) spectabilis which bears a distinct furrow along the suture; the microsculpture of the first whorls is more marked in the new species and in O. (D.) brincki, somewhat fainter in O. (D.) agostinhoi and absent in O. (A.) spectabilis. A more detailed comparison is shown in Table 3. At first sight Oxychilus (Drouetia) viridescens n.sp. could be confused with the sympatric O. (D.) brincki because both species have similar shells. However, a brief survey of simple morphometric characters (Fig. 2; Table 2) showed that, although with some overlap, the new species has about half a whorl less and is more depressed than O. (D.) brincki (Fig. 17). Because the palatal lip and the columellar lip of the shell run almost at the same plane, the aperture, seen from the bottom, is very narrow in the new species whereas it is extended in O. (D.) brinki. Moreover, fresh shells of the new species exhibit a conspicuous greenish colour whereas the shell of O. (D.) brincki has a more golden-brown pigmentation; the coloration around the umbilical area is grayish in the new species, but it is pinkish in O. (D.) brincki (Figs. 4 C, D). The colour pattern of the animal in both species shows also some differentiation, with greenish tones and smaller, sparser and whitish blotches on the mantle, as well as a whitish foot predominating in the new species (Figs. 4 A; 18 A), whereas yellowish blotches predominate in the mantle of O. (D.) brincki, and its foot is typically yellowish to orange (Fig. 4 B). The mantle of O. (D.) agostinhoi may sometimes exhibit a greenish colour, but it is usually redish-brown with some small, whitish spots around the spire and large, black spots restricted to the apertural area, a feature common in the genus; the border of the mantle is black, the neck dark-blue with lighter-blue transverse stripes anteriorly, changing posteriorly to a lighter-blue background strewn with darker spots; foot light-blue, bordered by a dark-blue rim (Fig. 18 B). The reproductive system remains the most important source of characters by which the new species can be differentiated; however, care must be exercised when comparing structures, for the degree of relaxation at the time of death may affect the shape and the proportions of the various organs or parts thereof (Martins 1991). Also the degree of development may render some structures more evident at certain times of the year (Rodrigues et al. 1998; Cunha et al. 2001). In this work, only organs that do not depend entirely on the degree of maturation were used (e.g. penis vs. albumen gland) or structures that, although variable in other taxa, were observed to maintain a relatively constant pattern across different preserving situations. The reproductive system, and in particular the morphology of the penial complex, is very diverse in the four species from Santa Maria. The distal glandular vagina, the epiphallus with double swellings, and the very thin penis of O. (D.) viridescens n.sp. (Figs. 10, 11) are unique features in the Azorean oxychilids; the muscle strands attaching the distal portion of the epiphallus to the penial constriction are also seen in O. (D.) atlanticus (Fig. 19 A) and O. (D.) furtadoi Martins, 1989 (Fig. 20 B), although not as developed as in the new species. Some variability was found in the morphology of the male organ of O. (D.) brincki. The typical form, from Pico Alto, shows a stout, bulging penial complex and a short, thick epiphallus connected to the penial sheath through a very long, thin muscle, whereas the specimens from Santa Bárbara have a much thinner penis and epiphallus and a shorter muscular attachment of the latter structure. The internal morphology of the penis, however, with many long, homogeneous furrows running from the epiphallic pore, is a reliable indicator of the conspecificity of both populations; this morphology is also unique among Drouetia (Fig. 17 A, B). The penis of O. (D.) viridescens n.sp. and that of O. (D.) agostinhoi may exhibit a mid-length constriction (see Martins 1981), whose presence may depend on the degree of relaxation at the time of death. This constriction was never observed in the two other species. Oxychilus (D.) viridescens n.sp. and O. (D.) agostinhoi are also similar in the presence of a few strong pilasters inside the penis (Figs. 10; 11; 16 B); this resemblance, however, is probably misleading, for it can be attributed to the narrow penis of the former and to the small size of the latter species. TABLE 3. Comparison of the morphological and anatomical characters of Oxychilus (Drouetia) viridescens, n.sp. with the related species living in Santa Maria, O. (D.) brincki, O. (D.) agostinhoi and O. Atlantoxychilus) spectabilis. Characters O. (D.) viridescens O. (D.) brincki O. (D.) agostinhoi O. (A.) spectabilis Animalcoloration Neck color dark blue dark blue deep dark blue, transverse light streaks light pink, darker in front, faint gray running down toward foot blotches posteriorly Anterior tentacles faint blue dark blue dark blue, tips lighter light blue Posterior tentacles dark blue dark blue deep dark blue dark blue Posterior tentacle retractors entirely blackish entirely blackish entirely blackish dark blue, fading back until half neck Foot rim dark blue posteriorly only same color as foot sole almost continuously dark blue brownish, interrupted all along foot Foot sole Whitish green to dark yellow yellowish green to orange whitish pinkish Collar blackish near pneumostome, fading to blackish near pneumostome, fading to blackish all around pinkish all around pinkish on left side pinkish on left side Pneumostomal area all blackish pinkish above, dark blue underneath all blackish pink, faint bluish blotch underneath Mantle color brown pale brown dark yellow to brick red golden yellow Front blotch black, only on right side black, only on right side black, across front black, only on right side Mantle blotches light yellow, small, sparse whitish, large, abundant dark yellow, very small, very sparse whitish, large, abundant Shell Maximum diameter (mm) 9.0 8.9 5.1 5.5 Number of whorls 6.2 6.8 4.2 5 Spire moderate high flat moderate Aperture, basal view narrow very extended extended moderately extended General coloration greenish golden brown greenish golden brown Umbilical region grayish pinkish whitish golden brown Sculpture finely grooved spirally finely grooved spirally very finely grooved spirally smooth, w/ furrow Radula marginal teeth/half row 21 19 13 19 cusps of central tooth central cusp much longer central cusp much longer cusps small, equal central cusp much longer Mandible slender and curved slender and less curved slender and less curved very slender and straight Mantlecollar Right lateral lobe elon, Published as part of De Frias Martins, António M., Brito, Carlos P. & Backeljau, Thierry, 2013, Oxychilus (Drouetia) viridescens (Gastropoda: Pulmonata: Oxychilidae), a new species from Santa Maria, Açores, and a review of the subgenus, pp. 343-368 in Zootaxa 3619 (3) on pages 345-356, DOI: 10.11646/zootaxa.3619.3.5, http://zenodo.org/record/217371

Family Oxychilidae P. Hesse, 1927 (1879), Published as part of De Frias Martins, António M., Brito, Carlos P. & Backeljau, Thierry, 2013, Oxychilus (Drouetia) viridescens (Gastropoda: Pulmonata: Oxychilidae), a new species from Santa Maria, Açores, and a review of the subgenus, pp. 343-368 in Zootaxa 3619 (3) on page 344, DOI: 10.11646/zootaxa.3619.3.5, http://zenodo.org/record/217371

Genus Oxychilus Fitzinger, 1833, Published as part of De Frias Martins, António M., Brito, Carlos P. & Backeljau, Thierry, 2013, Oxychilus (Drouetia) viridescens (Gastropoda: Pulmonata: Oxychilidae), a new species from Santa Maria, Açores, and a review of the subgenus, pp. 343-368 in Zootaxa 3619 (3) on page 344, DOI: 10.11646/zootaxa.3619.3.5, http://zenodo.org/record/217371

Reviewing Drouetia Gude, 1911 and Atlantoxychilus Riedel, 1964 The genus with the highest number of endemic taxa in the Azorean biota is the molluscan Oxychilus, of which the subgenus Drouetia accounts for 8 of the 15 hitherto described endemic species of that genus. However, Drouetia was first monotypic (Gude 1911), for its type species, Helix atlantica, was considered to live throughout most islands of the Azores (Morelet 1860). It was only through Riedel’s (1964) anatomical research that the diversity of Drouetia started to be noticed, and Martins (2005) has provided evidence that the number of known species remains understated. Besides the three species from Santa Maria sufficiently dealt with above, five more species are known: two from São Miguel, O. (D.) atlanticus and O. (D.) batalhanus de Winter, 1989; two from Terceira, O. (D.) miceui Martins, 1989 and O. (D.) furtadoi; one from Faial, O.(D.) minor Riedel, 1964. Atlantoxychilus is represented by one, already mentioned species: O. (A.) spectabilis. Oxychilus (Drouetia) atlanticus (Fig. 18 C, 19, 20 A). The history of this taxon has been dealt with above (see Remarks). Martins (1991) first reported the anatomical variability of O. (D.) atlanticus throughout São Miguel and, although calling attention to variability as an artifact of preservation, recognized the possibility of additional species, namely Riedel’s (1964) “small form” and the population of Sete Cidades. Nevertheless, Martins’ (2005) extended analysis interpreted those differences as allotopic, demic variability. However, further anatomical and morphometric research has revealed syntopic variability, with different shell and genitalia patterns existing sympatrically, thus suggesting the existence of various taxonomic units in São Miguel (Martins et al. 2010), the description of which is presently under way. Oxychilus (D.) atlanticus needed, thus, to be unequivocally characterized. To this end, a neotype was proposed so to restrict O. (D.) atlanticus to the large shell phenotype living in Sete Cidades, São Miguel (ICZN Case 3553; Martins et al. 2011). However, this proposal is no longer needed, since the recent discovery of Drouët´s collection of Azorean material, with specimens from São Miguel, provided a suitable lectotype for Helix atlantica (MJSD. 2012.CO. 68 a; Fig. 19). The specimen selected is the largest of a lot of 48 (diameter 7.8 mm; height, 4.8 mm; number of whorls, 6) and conforms with the measurements given in the original description (maximum diameter, 8 mm; height, 5 mm; Morelet & Drouët 1857). Due to the taxonomic and morphological complexity of Drouetia in São Miguel and the importance of anatomy and locality for species identification (Martins 1991, 2005), the type locality for Helix atlantica Morelet & Drouët is herein restricted to Caldeira das Sete Cidades. Indistinguishable from the following species on the basis of shell morphology alone, O. (D.) atlanticus has a darker border of the mantle and the foot sole is yellowish; however, it is readily identified anatomically, namely by the long epiphallus, the long and narrow bursa duct and large bursa, and, inside the penis, the reticulate ornamentation on the penial caecum and around the epiphallic pore. Oxychilus (D.) batalhanus de Winter, 1989 (Fig. 18 D, 20 B). Conchologically indistinguishable from the previous species, O. (D.) batalhanus was proposed on the basis of the morphology of the penial complex (de Winter 1989). Martins (1991) showed that the proportions of various structures of the penial complex, namely the penial caecum, can change as an artefact of preservation methods and, therefore, are by themselves unreliable diagnostic characters. For that reason O. (D.) batalhanus was considered a junior synonym of O. (D.) atlanticus (Martins 2005). Recent research based mostly on the internal morphology of the penis (Martins et al. 2010) has provided evidence for the existence of various taxonomic units in São Miguel; restriction of O. (D.) atlanticus to the anatomically different Sete Cidades population restores the validity of O. (D.) batalhanus. Although very variable, when compared with the previous species O. (D.) batalhanus shows a lighter blue border of the mantle and the foot is pinkish to orange, sometimes greenish; it is diagnosed by the short vagina, the membranous proximal penis with weak crests radiating from the epiphallic pore, the strongly muscular distal penis with strong pilasters inside. Oxychilus (D.) batalhanus is distributed throughout the entire island of São Miguel. Oxychilus (D.) miceui Martins, 1989 (Figs. 18 E, 21 A). This species lives on the mountains of Terceira and is characterized by the yellow to whitish mantle spotted with small brown to blackish patches, contrasting with the dark-blue mantle border and neck, fading to light-blue toward the foot. The shell has a depressed spire, the last whorl a quadrangular profile, the aperture is slightly wider than that of the following species. Anatomically this species is characterized by a long, convoluted oviduct and moderately long vagina, a membranous proximal penis and penial caecum cumulatively as long as the muscular distal penis, both units usually separated by a constriction. Oxychilus (D.) furtadoi Martins, 1989 (Figs. 18 F, 21 B). This species lives at lower altitude around the town of Angra do Heroísmo, Terceira. Conchologically similar to O. (D.) miceui, it has a slightly narrower aperture. The mantle has a greenish-brown background spotted with sparse, small whitish patches, the mantle border and neck light-blue, turning pinkish toward the foot. The reproductive anatomy is characterized by a long, narrow vagina, a short, membranous proximal penis and penial caecum, a long, narrow, muscular distal penis and an equally long penial sheath; the epiphallus is long, the distal third connected to the distal penis by muscular strands. Oxychilus (D.) minor Riedel, 1964 (Figs. 18 G, 21 C). This species was first referred by Morelet (1860) as variety “β minor ”, and it was Riedel (1964) who considered it a discrete taxon, attributing authorship and date to Morelet (1860). Bank et al. (2002), however, interpreted Morelet’s word “ minor ” not as a name but as part of the description, thus attributing authorship and date to Riedel (1964). The animal of O. (D.) minor is characteristically pink, the mantle mottled with white patches and rare dark spots, posterior tentacles dark-blue becoming lighter toward the base. The shell has a depressed spire and the aperture is somewhat wide. The most peculiar anatomic feature is the stout, strongly muscular penis without noticeable constriction, with strong pilasters running back to the penial caecum. Oxychilus (Atlantoxychilus) spectabilis (Milne-Edwards, 1885) (Fig. 18 H). Hausdorf (1993) considered Helix atlantica var. spectabilis Morelet, 1860 to be a primary homonym of Helix spectabilis Pfeiffer, 1844, and introduced accordingly the new name Oxchilus (Atlantoxychilus) riedeli. However, Bank et al (2002) considered Hausdorf’s (1993) nomenclatorial action invalid, for Morelet’s (1860) indication of a “γ var. spectabilis ” did not constitute attribution of a name to the variety, the word “ spectabilis ” instead being part of the description of variety γ. The name was validly introduced by Milne-Edwards (1885) as Hyalinia spectabilis, which is not preoccupied. Some aspects of this species were already dealt with, and only a brief morphological characterization will be added. The mantle is brown, crossed by elongated, irregular golden-brown blotches; border of mantle light-brown; neck dark-brown, sharply separated from the golden-brown foot which is surrounded by an intermittent brown rim., Published as part of De Frias Martins, António M., Brito, Carlos P. & Backeljau, Thierry, 2013, Oxychilus (Drouetia) viridescens (Gastropoda: Pulmonata: Oxychilidae), a new species from Santa Maria, Açores, and a review of the subgenus, pp. 343-368 in Zootaxa 3619 (3) on pages 361-364, DOI: 10.11646/zootaxa.3619.3.5, http://zenodo.org/record/217371

Oxychilus (Drouetia) viridescens n.sp. is described from Santa Maria Island, Açores. It is conchologically similar to the sympatric Oxychilus (Drouetia) brincki Riedel, 1964, from which it is distinguished by the greenish coloration, the flatter spire and the slightly smaller number of whorls. Anatomically, the new species differs from all consubgenerics by the genital morphology: the penis is very thin, the distal half is wrapped in a very thick penial sheath; the epiphallus has two distinct portions, the proximal one attached to the edge of the penial sheath, the distal one attached to a constriction near mid-length of the penis; the atrial end of the vagina has a spongy, glandular appearance. A detailed morphological and anatomical comparison of the new species with the non-umbilicated Oxychilusspecies of Santa Maria is presented. The species of Drouetia are reviewed and an identification key is provided.

Bu çalışmanın amacı, evrim karşıtı yaratılışçı savların alaşağı edilmesine taksonominin önemli katkı yapabileceğini gözler önüne sermek. Makalenin yöntemini, Türkiyede Harun Yahya mahlasıyla faaliyet gösteren yaratılış yanlısı cephenin başlıca eseri Yaratılış Atlasının taksonomi temelini dikkatle gözden geçirmek oluşturuyor. Yaratılış Atlasının temel hedefi, fosillerin ve yaşayan organizmaların özdeş olduğunu, yani canlıların yaratılıştan beri değişmediğini sergilemek suretiyle evrimin gerçekleşmediğini kanıtlamak. Fakat bu savın üzerine inşa edildiği taksonomi temeli, gülünçlük derecesine varacak kadar baştan sona hatalı. Öyle ki, Yaratılış Atlasının, evrim kuramına karşı ciddi bir meydan okuma teşkil etmeyi bir kenara bırakın, zerre biyolojik geçerliliği dahi yok.

The geographical distribution of the Rissoidae in the Atlantic Ocean and Mediterranean Sea was compiled and is up-to-date until July 2011. All species were classified according to their mode of larval development (planktotrophic and nonplanktotrophic), and bathymetrical zonation (shallow species—those living between the intertidal and 50 m depth, and deep species—those usually living below 50 m depth). 542 species of Rissoidae are presently reported to the Atlantic Ocean and the Mediterranean Sea, belonging to 33 genera. The Mediterranean Sea is the most diverse site, followed by Canary Islands, Caribbean, Portugal, and Cape Verde. The Mediterranean and Cape Verde Islands are the sites with higher numbers of endemic species, with predominance of Alvania spp. in the first site, and of Alvania and Schwartziella at Cape Verde. In spite of the large number of rissoids at Madeira archipelago, a large number of species are shared with Canaries, Selvagens, and the Azores, thus only about 8% are endemic to the Madeira archipelago. Most of the 542-rissoid species that live in the Atlantic and in the Mediterranean are shallow species (323), 110 are considered as deep species, and 23 species are reported in both shallow and deep waters. There is a predominance of nonplanktotrophs in islands, seamounts, and at high and medium latitudes. This pattern is particularly evident in the genera Crisilla, Manzonia, Onoba, Porosalvania, Schwartziella, and Setia. Planktotrophic species are more abundant in the eastern Atlantic and in the Mediterranean Sea. The results of the analysis of the probable directions of faunal flows support the patterns found by both the Parsimony Analysis of Endemicity and the geographical distribution. Four main source areas for rissoids emerge: Mediterranean, Caribbean, Canaries/Madeira archipelagos, and the Cape Verde archipelago. We must stress the high percentage of endemics that occurs in the isolated islands of Saint Helena, Tristan da Cunha, Cape Verde archipelago and also the Azores, thus reinforcing the legislative protective actions that the local governments have implemented in these islands during the recent years.

The present work aims at illustrating how taxonomy can provide an essential contribution to debunk creationist anti-evolutionary arguments. It does so by scrutinizing the taxonomic basis of the Atlas of Creation, the major opus of the Turkish creationist consortium operating under the pen name Harun Yahya. The basic aim of the Atlas of Creation is to prove that evolution does not occur by showing that fossil and recent organisms are identical, i.e. have not changed since their divine creation. However, the taxonomic foundation onto which this argument is built is completely flawed, up to the point of being hilarious. As such the Atlas of Creation has not the slightest biological credibility, let alone that it would represent a serious challenge for evolutionary theory. So taxonomy can indeed eff ectively contribute to countering creationist theories.

The purpose of this application, under Article 75.6 of the Code, is to conserve the current usage of the name Helix atlantica Morelet & Drouët, 1857 (currently Oxychilus (Drouetia) atlanticus) for a species of pulmonate gastropod by designating a neotype. The syntypes of this species housed in the Natural History Museum, London are not in taxonomic accord with the prevailing usage. Originally H. atlantica was said to occur in most islands of the archipelago of the Azores, but later this name was uniformly used for specimens from São Miguel Island only, while the syntypes are from Santa Maria Island. We request the Commission use its plenary power to set aside the existing name-bearing types and to designate a neotype from São Miguel Island, to conserve the prevailing usage and concept of the species.

Freshwater bivalves of the Unionoidea provide important ecosystem functions, yet many of their populations are in decline. In the present work, we comprehensively review the status of all of the currently described species in Europe, addressing their phylogenetic and taxonomic relations, their distribution and conservation status, as well as their habitat preferences and main threats in order to suggest prospective conservation action. Information on the current status of Unionoids in Europe is very unevenly distributed with rather detailed information available for flagship species such as the freshwater pearl mussel (Margaritifera margaritifera) and little or no information available on other species. Similarly, in certain regions such as the British Isles, the Iberian Peninsula and central Europe, information is more consistent than in other parts of Europe. In order to make conservation more effective in the future, we suggest a more standardized international approach to surveying European freshwater bivalves that need to encompass more ecological and genetic data.