Spiripockia puncata, Simone, 2012

Simone, Luiz Ricardo L., 2012, A New Genus And Species Of Cavernicolous Pomatiopsidae (Mollusca, Caenogastropoda) In Bahia, Brazil, Papéis Avulsos de Zoologia (São Paulo) 52 (40), pp. 515-524 : 515-524

Spiripockia puncata new species

( Figs. 1-33 )

Types: Holotype MZSP 105000 . Paratypes: MZSP 104435 , 19 specimens , MNRJ 30503 , 1 specimen , USNM 2060411 , 1 specimen , all from type locality.

Type locality: BRAZIL. Bahia; Serra Ramalho Karst area, Middle São Francisco River basin, Lapa dos Peixes cave , 13°49’21.78”S, 43°57’24.39”W (M.E. Bichuette col., 29/vii/2005) .

Diagnosis: Shell weakly elongated; walls thin, fragile, translucent, unpigmented. Sculptured by pustules somewhat spirally aligned, possessing periostracum hair on tip of pustules (sometimes absent). Peristome expanded in plane ~90° in relation to last quarter whorl. Umbilicus opened. Strong pair of ventral snout retractor muscles passing through nerve ring. Radular rachidian with 6 apical and 3 pairs of lateral cusps, ~10 terminal cusps in radular lateral and marginal teeth. Eyes absent. Head-foot unpigmented. Osphradium short, arched. Gill filaments with rounded tip. Salivary glands short, small. Odontophore lacking pair of ventral tensor muscles (m11). Genital pallial gonoducts closed (tubular). Prostate flattened, with vas deferens inserting subterminally. Penis duct narrow and weakly sinuous. Pallial oviduct simple anteriorly; posterior region possessing convoluted bypass connecting base of bulged portion of transition between visceral and pallial oviducts with base of seminal receptacle; spermathecal duct complete, opening close to anus level. Nerve ring with well delimited ganglia.

DESCRIPTION

Shell ( Figs. 1-5, 8-14 ): Up to 5 mm; about as wide as long, turbiform to slightly turriform. Spire angle ~50°. Color pale beige to white, translucent. Protoconch occupying ~20% of shell width and ~7% of length; globose, smooth, transparent ( Figs. 3, 5, 10 , 13 ). Transition protoconch-teleoconch weak, orthocline. Teleoconch up to 4 convex whorls; suture deep, with ~90°; whorls somewhat uniform, except for last whorl in adult specimens, with bluntly pointed projection located approximately in opposed side from aperture ( Figs. 2, 5, 11 ) (more visible in apical or anterior views); projection absent in younger specimens ( Figs. 8-9 ); being clearly derived from previous aperture. Sculpture minute pustules aligned in spiral lines ( Figs. 12, 14 ), ~6 doted spiral lines, equidistantly spaced, in penultimate whorl; each line with ~40 pustules in penultimate whorl disposed somewhat alternately each line in relation to neighbor lines ( Figs. 1-3, 10-14 ); each pustule in form of small, circular convexity, separated from neighbor pustules by smooth distance equivalent to twice pustules width ( Fig. 12 ); pustules somewhat uniformly distributed, and sometimes forming wide angulation on shell surface ( Fig. 14 ); this dotted sculpture absent in ~15% of specimens, possessing completely smooth outer surface ( Figs. 4-5 ); periostracum possessing 5-6 axially aligned hair on pustules tip ( Figs. 3, 10-11 ), looking like flexible scales. Sculpture on younger specimens similar to this above described, but with pustule located closer to each other and with 4 inferior lines located closer to each other and far from subsutural line ( Figs. 8-9 ); gradually after 2-3 whorls sculpture changing to adult pattern. Peristome expanding in plane ~90° in relation to terminal region of body whorl ( Figs. 1-5, 10-11 ) in mature specimens; expansion edges extremely fragile and somewhat irregular (apparently to fit in substrate), particularly wider in anterior region ( Fig. 1 ) and narrower in columellar implantation; expansion extending ~15 % shell width. Aperture oval, superior angulation blunt; remaining somewhat rounded. Umbilicus opened and relatively wide ( Figs. 2, 4, 11 ), occupying ~15% of shell width (excluding peristome); no callus, except for short and narrow portion of peristome attached to preceding whorl ( Figs. 2-4, 10-11 ).

Head-foot ( Figs. 19-21 ): Relatively small, stubby, unpigmented. Foot thick, as wide as shell aperture. Mesopodium thick, flanked dorsally by shallow lateral furrows ( Fig. 21 : ft). Anterior furrow of pedal glands (pg) deep, restricted to anterior edge ( Figs. 19-20 ). Opercular pad ( Fig. 21 : op) elliptic, terminal, occupying half of posterior foot dorsal surface. Head bulbous, with ~85% of food width; pair of cephalic tentacles lateral positioned ( Figs. 19-20, 23 : te), each tentacle simple, thick, with ~twice foot length; no detectable eye. Snout with ~twice tentacles width and ~half tentacles length (sn); anterior end weakly bilobed, mouth oval, wide, subterminal, ventral ( Figs. 23 : mo). Columellar muscle thick, ~3/4 whorl. Haemocoel elliptical, on central region of head-foot ( Fig. 23 ).

Operculum ( Figs. 6-7 ): Corneous, thin, translucent, yellow-beige, flexible, paucispiral. Outline ellipticalalmost circular. Edges thin. Nucleus located in middle region of interior half, weakly dislocated internally ( Fig. 6 ); from nucleus, ~2 whorls uniformly growing, appearing; outer surface also sculptured by weak undulations parallel to outer edge. Inner surface glossy, scar elliptic, occupying ~half of inner surface; location dislocated to internal edge, but not touching internal edge. Occupies entire shell aperture ( Figs. 3, 10-11 ).

Mantle organs ( Figs. 22, 27 ): Somewhat narrow, with ~1 whorl in length. Mantle edge simple, weakly thick; unpigmented. Osphradium short (os), curved (concavity left), simple; length ~6% pallial cavity length; located in anterior-left corner of cavity, close to mantle border. Gill elongated, narrow, with ~85% of pallial cavity length and ~25% of cavity width; anterior end bluntly pointed, close to mantle border; posterior region narrowing gradually, filaments ending at some distance from pericardium; gill filaments somewhat triangular, with distal tip rounded ( Fig. 27 : gi). Between gill and rectum a narrow distance equivalent to 10% of pallial cavity width. Hypobranchial gland inconspicuous. Rectum wide, reaching up to half of pallial cavity width in some points; bearing aligned series of elliptical fecal pellets (fe) disposed transversally or weakly oblique, easily seen by translucence ( Figs. 1-3, 10-11 ); rectum displaced from right mantle cavity edge by pallial genital ducts. Anus simple, shortly siphoned, distant from mantle border ~10% of cavity length, in anterior-right corner of pallial roof. Genital ducts running along right edge, relatively massive, described below.

Visceral mass ( Figs. 22 , 31 ): Length ~3 whorls, keeping ~2 first shell whorls empty in adult specimens ( Figs. 2-3, 10 ). Color of most structures pale beige to white. Stomach as anterior structure, compressing ventrally small reno-pericardial structures; stomach of ~0.5 whorl and with almost entire adjacent whorl width. Digestive gland of ~2 whorls, mostly posterior to stomach. Gonad running along columellar surface of each whorl when mature, weakly distinct from digestive gland. Other genital and digestive details below.

Circulatory and excretory systems ( Fig. 31 ): Pericardium narrow, located transversely between stomach and pallial cavity ( Fig. 22 : pc), volume ~1/20 of that of visceral mass; auricle anterior, small, just posterior to posterior end of ctenidial vein; ventricle posterior, simple. Kidney minute, weakly smaller than pericardium, located on right side of pallial cavity posterior end; inner tissue totally solid, white. Nephrostome (ne) small, transverse, located close to pericardium.

Digestive system ( Figs. 22-26 , 28 ): Mouth in anteroventral end of snout ( Fig. 23 : mo). Pair of strong ventral retractor muscles of snout and mouth ( Figs. 23-24 : rm); originating in middle level of haemocoelic ventral floor; running close to median line towards anterior, flanking ventral surface of buccal mass, passing through nerve ring ( Figs. 23 , 33 ); inserting along ventral wall of snout, close to ventral border of mouth. Buccal mass bulged, occupying entire snout inner surface and ~1/3 of haemocoelic volume. Pair of jaw plates ( Fig. 25 : jw) somewhat separated from each other; each jaw oval and very thin, translucent. Odontophore spherical, with ~half of buccal mass volume. Odontophore muscles ( Figs. 24-26 , 28 ): mj, pair of jaw and peribuccal muscles, working also as odontophore protractors, originating in lateral and ventral region of mouth, running towards posterior as part of oral tube along ~half odontophore length ( Fig. 24 ), inserting in latero-ventral mid region of odontophore cartilages ( Fig. 26 ); m2, pair of posterior retractor muscles of odontophore ( Figs. 24-25 ), narrow, originating in lateral region of haemocoel inner surface, in its middle level, running towards anterior a distance slightly longer than buccal mass length, inserting in postero-lateral region of odontophore cartilages ( Fig. 28 ); m4, pair of main dorsal tensor muscle of radula ( Fig. 28 ), broad and thick, surrounding outer lateral surface of odontophore cartilages, originating from their ventro-lateral surface, inserting in lateral edges of subradular cartilage in its region in buccal cavity, and also in radular sac region preceding buccal cavity ( Fig. 28 : ir); m5, pair of secondary dorsal tensor muscles of radula ( Figs. 26 , 28 ), narrow and thick, originating in posterior edge of odontophore cartilages, running towards medial and anterior, between cartilages, inserting in ventral side of radular ribbon in its region exposed in buccal cavity ( Figs. 28 : is); m6, horizontal muscle, thin and wide, connecting ventral edge of both odontophore cartilages along ~75% of their length ( Fig. 28 ); m10, pair of ventral protractor muscle of buccal mass ( Figs. 24, 26 ), relatively wide and thick, originating in ventral edge of mouth, just ventral to retractor muscle (mr) origin, running towards posterior a distance equivalent to odontophore length, inserting in posterior-ventral edge of odontophore cartilages. Subradular cartilage relatively wide in region of buccal cavity ( Fig. 25 : sc). Odontophore cartilages elliptic, somewhat flattened laterally, anterior edge weakly narrower than posterior edge ( Fig. 28 : oc). Radular sac with length ~3 times

that of odontophore ( Figs. 24-26 : rs), and ~1/4 odontophore width; radular nucleus (rn) weakly broader.

Radular tooth ( Figs. 15-18 ): rachidian tooth triangular, distal tip curved inwards, with ~16% of radular ribbon width, about as tall as wide, base simple, weakly arched, 3 pairs of latero-basal cusps ( Figs. 16-18 ), each cusp small, triangular, pointed tip; 5-7 terminal triangular cusps, central cusp larger, cusps weakly diminishing towards lateral, restricted to distal, curved edge; lateral tooth with main region rectangular, with ~double rachidian height and its same width, ~15 cusps similar to those of rachidian, cusps smaller in both ends, being gradually larger towards middleweakly lateral region ( Figs. 16-17 ), basal region widening obliquely externally ( Figs. 15, 17 ) along distance equivalent to ~30% radula width, being covered by marginal teeth ( Figs. 17-18 ); inner and outer lateral tooth similarly shaped, being outer tooth ~30% narrower than inner marginal tooth, ~double length as lateral tooth and ~40% narrower, general form as rod curved inwards at tip, tip flattened, bearing ~13 (inner) and ~10 (outer) terminal cusps of similar characters as lateral tooth cusps.

Salivary gland small ( Figs. 23-24 : sg), white, with maximum length ~half buccal mass length, and sometimes smaller; about 3 times longer than wide, tip rounded; salivary aperture in postero-lateral region of oral cavity ( Fig. 25 : sa). Dorsal folds of buccal mass ( Fig. 25 : df) smooth, simple, wide, located close to each other. Esophagus simple and sinuous along haemocoel ( Figs. 23-24 : es), generally with anterior glandular enlargement ( Fig. 24 ), but sometimes (~30%) with same width along length; most remaining esophageal inner surface simple, lacking folds; posterior esophagus ( Fig. 22 : es) narrow, inserting in ventral-mid region of stomach. Stomach dimensions and positions above described (visceral mass); possessing main gastric chamber posterior, with rounded posterior surface, and narrow style sac ( Figs. 22 : ss), with ~half remaining gastric dimensions. Style sac totally separated from intestine; esophagus inserting just ventrally to origins of style sac and intestine, on anterior stomach side; duct to digestive gland as wide as posterior esophagus, originating at short distance posterior to esophageal insertion ( Fig. 22 : dd), running towards posterior. Intestine originating dorsally and at left from esophageal insertion ( Fig. 22 : in), with ~double esophagus width, and at left from style sac; running surrounding externally style sac up to dorsal region of kidney, broadening in region preceding pallial cavity. Rectum, fecal pellets and anus above described (pallial cavity). Fecal pellets formed only after renal portion of intestine ( Figs. 11 , 22 ).

Genital system: Male ( Figs. 19 , 29, 31 ): Testis restrict- ed to posterior half of digestive gland ( Fig. 31 : ts). Seminal vesicle (sv) weakly convolute, with 3-4 zigzag loops in columelar region of visceral mass preceding stomach, color pale grey-iridescent; vas deferens relatively straight in gastric and renal region, inserting in prostate subterminally ( Fig. 31 : vd). Prostate with ~1/4 pallial cavity width, somewhat dorsoventrally flattened, white, totally closed (tubular); inner lumen simple, flat ( Fig. 27 : pt). Vas deferens originating subterminally from prostate anterior region ( Fig. 31 : vd) in level between anterior and mid thirds of pallial cavity; in short distance penetrating in floor of pallial cavity by side of penis base, running immersed in integument ( Figs. 19 : vd, 29: pd). Penis ( Figs. 19-29 : pe) simple, curved, base broad, gradually tapering up to sharp pointed tip. Penis duct seen by translucence, color pale-green-iridescent, performing weak zigzag coils along outer, almost central penial region, up to penis distal tip ( Fig. 29 : pd); aperture distal, simple, small (pa).

Female ( Figs. 22 , 32 ): Visceral structures similar to those of males; ovary (oy) somewhat broader than testis. Visceral oviduct very narrow, running along middle level of columellar surface of visceral mass ~half whorl (vo). Visceral oviduct inserting terminally in complex posterior region of pallial oviduct ( Fig. 32 ) in bulged region of oviduct (co) with simple glandular walls and hollow inside. This bulged region continuing to albumen gland (ag) strongly curved in ~180°. Spermathecal duct (of) originating in ventral-left side of albumen gland, very narrow but with thick walls, running along right edge of pallial cavity ventral to remaining pallial oviduct ~90% of pallial cavity length; opening simple by side and ventral to main female pore ( Figs. 22 : fp). Seminal receptacle (rs) bulging subterminally in posterior region of pallial oviduct, possessing two successive bulbs or sometimes horseshoe-shaped; inserting by narrow duct in adjacent left side of posterior end of capsule gland. Sperm duct, or bypass (sd) as convoluted duct connecting anterior region of bulged region of oviduct (co) with base of seminal receptacle (rs); posterior half clearly narrower, gradually broadening in anterior half. Capsule gland (cg) occupying ~80% of pallial oviduct length; walls thick glandular, white, lumen flattened ( Fig. 22 ); short terminal atrium with walls weakly thick, tapering up to female pore. Female pore shortly siphoned, papilla-like, turned anteriorly, located close to and at right of anus. No special female genital structure in head-foot ( Figs. 20-21 ).

Central nervous system ( Figs. 30, 33 ): Nerve ring located just posterior to buccal mass, with pedal ganglia weakly more anterior ( Fig. 23 : nr) than remaining ganglia. Each cerebral ganglion (ce) oval, with size equivalent to esophageal section; cerebral commissure narrow, with ~half-length as each ganglion. Pleural ganglia (pl) with ~half size of cerebral ganglia, located just ventral to them. Each pedal ganglion (pn) weakly larger than cerebral ganglion, somewhat spherical, located very close to each other (pedal commissure extremely short). Cerebro-pedal and pleuro-pedal connectives about as long as pedal ganglia ( Fig. 30 ). Subesophageal ganglion (su) with ~half pleural ganglion size, located a distance from right pleural ganglion equivalent to 1.5 times each cerebral ganglion length. Pair of statocysts (sy) located in ventro-posterior side of pedal ganglia; with large, single statolith inside. Single pair of tentacular nerve (tn), lacking optical nerve.

Measurements (in mm): Holotype: 4.6 by 4.3; paratypes: 2♀: 3.3 by 3.1; 4♂: 3.3 by 3.5; 5♀: 3.6 by 3.4.

Distribution: Only known in the type locality (Lapa dos Peixes cave).

Habitat: In a cave surrounded by Caatinga semi-arid environment, attached to rocks inside a small stream.

Material examined: Types.

Figures

FIGURES 1‑11: Spiripockia punctata shell and operculum: 1) holotype, dorsal view (H 4.6 mm); 2) same, apertural-slightly anterior view; 3) same, apertural view; 4) paratype MZSP 104435 2♀ with specimens extracted, apertural view (H 3.3 mm); 5) same, apical-slightly apertural view; 6) holotype operculum, outer view (H 1.2 mm); 7) same, inner view; 8) young paratype, apertural view; 9) same, another specimen, left view; 10) paratype 6♀, apertural-slightly left view (H 3.4 mm); 11) same, anterior-slightly apertural view.

FIGURES 12‑18: Spiripockia punctata hard parts in SEM: 12) paratype MZSP 104435 3♂, detail of penultimate whorl, dorsal view, scale = 200 µm; 13) same, detail of apical region in profile, scale = 200 µm; 14) same, whole dorsal view (H 3.9 mm); 15) radula, partial whole view, scale = 20 µm; 16) same, detail of central region, scale = 10 µm; 17) same, wider magnification, scale = 10 µm; 18) same, detail of more lateral region, scale = 10 µm.

FIGURES 19‑27: Spiripockia punctata anatomy: 19) head-foot, male, dorsal view; 20) same, female; 21) same, right view; 22) pallial cavity roof and partially uncoiled visceral mass, female, ventral view, some genital structures displaced, transverse section in indicated region of pallial oviduct also shown; 23) head and haemocoel, ventral view, foot and columellar muscle removed; 24) foregut, right-slightly dorsal view; 25) same, ventral view, odontophore partially removed and deflected, esophagus partially sectioned longitudinally; 26) odontophore, ventral view, radula partially deflected upwards; 27) pallial cavity hoof, transverse section in middle level of gill. Scales = 0.5 mm.

FIGURES 28‑33: Spiripockia punctata anatomy: 28) odontophore, dorsal view, radula, outer layer of muscles and membranes removed, both cartilages deflected; 29) penis, ventral view, adjacent region of integument also shown, penis duct seen by translucence; 30) nerve ring, right view; 31) part of pallial cavity roof and partially uncoiled visceral mass, male, ventral view; 32) posterior end of pallial oviduct, ventral view; 33) nerve ring, dorsal view, topology of adjacent retractor muscle also shown. Scales = 0.5 mm.