Clinispira insolita Simone & Casati, 2013, new species
Creators: name: Simone, Luiz Ricardo L.
name: Casati, Rafael
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Stylommatophora
Streptaxidae
Clinispira
Clinispira insolita

description: Clinispira insolita new species
(Figs. 2–15)
Types. Holotype MZSP 111847. Paratypes MZSP 111828, 84 eroded shells (sta. P4), MZSP 111829, 5 shells (sta. P3), MZSP 111830, 5 shells (sta. P3), MZSP 111831, 4 shells (sta. P2), MZSP 111832, 5 shells (sta. P1), MZSP 111833, 1 shell (sta. P1), MZSP 111834, 2 shells (sta. P1), MZSP 111846, 8 shells (sta. P1) (Figs. 8–10), MZSP 112369, 3 shells (Figs. 11–13), MZSP 112426, 1 young shell (Figs 14–15), USNM, 2 shells; MNRJ, 2 shells. All from type locality.
Type locality. BRAZIL. Piauí; Serra da Capivara; Coronel José Dias municipality, close to Sítio do Mocó town, Cave Toca de Cima dos Pilão, 8°51’47.10”S 42°33’26.96”W (R. Casati col, 2012).
Description. Shell of about 15 mm. Color pale beige to pale brown, sometimes translucent (Figs. 11–13). Periostracum thin, pale-brown (Figs. 11–12). Most basal portion of adult and young specimens bulimoid (Fig. 14). Protoconch of 2 whorls, smooth, shining (Fig. 15), suture well-marked (Figs. 2, 4, 5, 7, 8, 12, 14); occupying ~1/6 of shell dorsal width. Spire of ~5 whorls, conic, angle ~65°; suture shallow but well-marked. Sculpture uniform series of axial, narrow, rather irregular undulations, from suture to suture, ~ 60 in penultimate whorl. Body whorl abruptly deviating perpendicularly from normal growth, edging outer side of preceding whorls towards apex, forming ark flanking outside entire shell; low peripheral carina from abrupt deviation up to region preceding aperture (Figs. 3, 6, 7, 9, 11); suture of this ark similar as remaining spire suture (Figs. 3, 9, 11). Spire axis situated ~30° in relation to arched body whorl (Figs. 2, 5, 8, 13). Aperture placed close and slightly ventral to apex (Figs. 2, 8, 13); peristome entirely deflected outwards, expanding ~30% width of preceding whorl; aperture greatly prosocline, deviating ventrally ~60° apertural plane from transverse section; pair of wide, longitudinal, irregular furrows in dorsal and left region preceding aperture (Figs. 4, 10, 12), corresponding to larger teeth of aperture. Aperture semi-circular, occupying ~1/5 of shell ventral surface; greatly occluded by series of narrow and tall teeth (Figs. 2, 5, 7, 9, 11), teeth fold-like, disposed perpendicularly to peristome; as follows (Fig. 7): 3 parietal (columellar or inner lip) teeth, located equidistant from each other on inner lip, infraparietalis (inferior) tooth ~8 times longer than wide, almost straight, edge broader than base, parietalis (middle) tooth similar to inferior tooth, but ~half its size, angularis (superior) tooth about as long as inferior tooth, but thinner and strongly arched (concavity inferior); single very large palatal tooth, Y-shaped tooth, corresponding to furrow of preceding dorsal region of aperture (Figs. 4, 10, 12), with ~1/3 of body whorl’s length, middle portion taller, inferior edge thick edged, forming ark (concavity inferior) in middle level of superior half of outer lip; 3 columellaris (inferior) teeth, placed approximately equidistant in inferior half of outer lip, middle tooth largest, ~10 times longer than wide, edge thicker than base, smoothly arched (concavity left), left and right columellaris teeth similar to middle tooth, being ~half its size; some specimens possessing secondary, minute, similar-shaped intermediary teeth between main columellaris teeth (Figs. 8, 9). Callus very thin, attached from third whorl to superior third part of fifty spire whorl (Figs. 3, 9, 11). Umbilicus wanting, occluded by arched body whorl (Figs. 3, 6, 9, 11).
Measurements (length, width and height in mm): Holotype (Figs. 2–7): 14.6 by 9.4 by 6.2; Paratypes MZSP 111846 (Figs. 8–10): 15.6 by 10.4 by 7.1; MZSP 112369 (Figs. 11–13): 14.0 by 10.0 by 6.6); MZSP 112426 (Figs. 14–15): 9.3 by 6.2.
Distribution. Only known from type locality.
Habitat. Caatinga semi-dry environment; collected inside caves.
Material examined. Types. Non-type material from type locality MZSP: 112353, 8 shells, 112360, 11 shells, 112365, 2 shells, 112375, 4 shells, 112396, 6 shells, 112404, 8 shells, 112419, 2 shells, 112428, 14 shells, 112435, 5 shells, 112440, 5 shells.
Etymology. The specific epithet is derived from the Latin insolitus, meaning unusual, uncommon, strange, and odd; an allusion to the strange shape of the body whorl.
Systematic remarks. The new genus Clinispira is clearly closely related to the South American genera Anostoma Waldehelm, 1807, Tomigerus Spix, 1827, and Biotocus Salgado & Leme, 1990; which are the genera with some degree of deviation of the body whorl and mostly well-developed teeth in a deflected peristome (Simone, 2006). Clinispira differs from Anostoma in being smaller in size (~ 15 mm, while the Anostoma are normally over 30 mm), a more developed teeth in peristome, a base of the shell somewhat bulimuloid (while Anostoma is discoid), and mainly by a smaller degree of deviation of body whorl (~60° instead of ~90°). Clinispira differs from Tomigerus and Biotocus (Salgado & Leme, 2000) in having a narrower basal shell, in lacking some degree of dorso-ventral compression, and by a larger degree of body whorl deviation (both previous known genera have only a short displacement of aperture towards the apex). However, the peristome of Clinispira is very similar in shape and teeth components to Tomigerus-Biotocus branch, which possibly indicates a closer relationship. The strange shape of Clinispira insolita dispenses any further comparisons to other genera or species.
The young specimens of Clinispira insolita are rare, and resemble a Bulimulus Leach, 1814 species (Fig. 14), except in having a smooth protoconch (Fig. 15) (it is reticulate in that genus). As a noteworthy variation, some specimens appear to be more elongated (Figs. 3, 4), while others are more circular in outline (Figs. 9, 10, 11, 12). The shell walls in most specimens are thick and opaque. However, a few specimens have thinner and translucent shell walls (Figs. 11–15). Whether this feature is related to youngness or a better preservation is not clear.
description: Published as part of Simone, Luiz Ricardo L. & Casati, Rafael, 2013, New land mollusk fauna from Serra da Capivara, Piauí, Brazil, with a new genus and five new species (Gastropoda: Orthalicoidea, Streptaxidae, Subulinidae), pp. 145-158 in Zootaxa 3683 (2) on pages 147-149, DOI: 10.11646/zootaxa.3683.2.4, http://zenodo.org/record/218653