Pyrgulopsis perturbata Hershler 1989

Pyrgulopsis perturbata Hershler, 1989

Pyrgulopsis perturbata Hershler, 1989:189, figs. 26e-g, 33–36.

DIAGNOSIS.—Shell ovate to low conical, medium to large-sized, narrowly umbilicate. Penial filament short, lobe medium length. Penial ornament a small Dg1, transverse terminal gland, and ventral gland.

DESCRIPTION.—Shell (Figure 23d) ovate to low conical; height, 2.7–4.0 mm; whorls, 4.25–5.0. Early protoconch very weakly punctate, otherwise near smooth. Teleoconch whorls slightly convex, sometimes shouldered; sculpture of very faint growth lines. Aperture broadly adnate to very slightly separated from body whorl. Inner lip complete, usually thick; columellar lip well reflected. Outer lip thick, slightly prosocline. Umbilicus rimate. Periostracum tan.

Operculum (Figure 23e,f) ovate, moderately dark amber; nucleus slightly eccentric; dorsal surface slightly frilled. Attachment scar margin weakly thickened all around, stronger along inner edge; callus weak.

Central radular tooth (Figure 38f) with slightly indented dorsal edge; lateral cusps, 5; central cusp rounded, much longer and slightly broader than laterals; basal cusps, 1, elongate-triangular, with strong dorsal support. Basal process medium width; basal sockets deep. Lateral margins thickened; neck weak-absent.

Cephalic tentacles pale to moderate brown-black. Snout light to dark gray. Foot light-moderate gray, with pigment darkest along anterior and posterior margins. Opercular lobe dark along margins, especially sides and outer edge. Neck pale to light gray. Pallial roof, visceral coil near pale to uniform black.

Ctenidial filaments, 27, tall and broad. Osphradium centered slightly posterior to middle of ctenidial axis. Kidney with large (35%) pallial bulge; opening thickened (not white). Stomach caecum prominent, broadly triangular.

Testis, 2 whorls, overlapping anterior stomach chamber to edge of style sac. Prostate gland with short pallial section; pallial vas deferens with weak proximal undulation. Penis (Figure 50a) large; filament short, narrow; lobe slightly longer than filament, broad, slightly oblique. Dgl small, positioned near base of filament. Terminal gland usually transverse, borne along ventral surface. Ventral gland (rarely split into two) borne on sub-terminal swelling. Filament dark.

Ovary, 1 whorl, overlapping posterior stomach chamber. Pallial albumen gland short. Albumen gland as long as capsule gland. Genital aperture a broad terminal slit with short vestibule. Coiled oviduct a short horizontal twist followed by broad horizontal loop, often kinked near mid-length, positioned slightly behind pallial wall. Oviduct and bursal duct join just behind pallial wall. Bursa copulatrix ovoid, short (32%–40%), narrow (33%), with 43%–80% of length posterior to gland. Bursal duct medium width, shallowly embedded in albumen gland, about as long as bursa copulatrix. Seminal receptacle pouch-like, narrow, folded, short, overlapping (or lateral to) proximal bursal duct.

TYPE LOCALITY.—Southern of two “Northwest Springs,” Fish Slough, Mono County, California (T 5S, R 32E, SE1/4 sec. 13). Holotype, USNM 860407; paratypes, USNM 853546.

DISTRIBUTION.—Headsprings in Fish Slough, Owens River drainage.

MATERIAL EXAMINED.—USNM 857990 (topotypes); USNM 857991, northern of two “Northwest Springs” (data as above).

Pyrgulopsis pilsbryana (Baily and Baily, 1952)

Paludestrina longinqua.—Pilsbry, 1899:122 [in part].—Stearns, 1901:285 [in part].—Henderson and Daniels, 1917:58, 59.—Henderson, 1924:190; 1931:110.—Chamberlain and Jones, 1929:177 [in part].

Amnicola pilsbryi Baily and Baily, 1951:50, pl. 4: fig. 3 [not Walker, 1906].—Baker, 1964:175.

Pyrgulopsis pilsbryi.—Hershler and Thompson, 1987:30.

Amnicola pilsbryana Baily and Baily, 1952:144 [new name for above].—Taylor, 1965:599.

Fontelicella pilsbryana.—Gregg and Taylor, 1965:108.—Taylor, 1975:152.—Burch, 1982:26.—Turgeon et al., 1988:61.

DIAGNOSIS.—Shell conical, medium to large-sized, umbilicate. Penial filament medium length, lobe short Penial ornament a small penial gland; small, weakly raised Dg3; and horizontal terminal gland.

DESCRIPTION.—Shell (Figure 23g) conical; height, 2.7–5.0 mm; whorls, 4–5. Protoconch near smooth except for a few adapical spiral lines on later portion. Teleoconch whorls highly convex, strongly shouldered; sculpture of variably expressed growth lines. Aperture narrowly adnate to body whorl, rarely separated. Inner lip complete, only very slightly thickened; columellar lip slightly reflected. Outer lip slightly prosocline. Umbilicus shallowly perforate. Periostracum brown.

Operculum (Figure 23h,i) ovate, amber, considerably darker in nuclear area; nucleus slightly eccentric; dorsal surface frilled. Attachment scar margin moderately thickened along inner edge (to nucleus), otherwise a faint trace; callus weak.

Central radular tooth (Figure 39a) with moderately indented dorsal edge; lateral cusps, 4; central cusp pointed, considerably broader, longer than laterals; basal cusps, 1, medium-sized, with weak-moderate dorsal support. Basal process narrow; basal sockets deep. Lateral margins thickened; neck weak.

Cephalic tentacles, snout, foot, neck light to dark brown-gray. Opercular lobe with dark internal pigment along sides. Neck sometimes with scattered dark internal granules. Pallial roof, visceral coil near uniform black. Entire animal sometimes black.

Ctenidial filaments, 23, medium height and width. Osphradium centrally positioned along ctenidial axis. Kidney opening slightly thickened. Stomach caecum prominent.

Testis, 1.5–2.0 whorls, overlapping stomach to posterior edge of style sac. Prostate gland with short pallial section; pallial vas deferens gently undulating proximally. Penis (Figure 50b) large; filament medium length, narrow; lobe short, tapered distally. Penial gland weak, covering only base of filament, sometimes extending slightly onto penis. Dg3 small, superficial or (less commonly) very weakly raised, near outer edge close to base of filament. Terminal gland horizontal (rarely split into two), borne distally, largely on ventral surface. Filament dark.

Ovary, 0.75–1.0 whorl, overlapping posterior stomach chamber. Pallial albumen gland short-long (15%–25%). Capsule gland as long as albumen gland. Genital aperture a subterminal pore without or with very short vestibule. Coiled oviduct a slight posterior oblique twist followed by broad horizontal loop slightly behind pallial wall. Oviduct and bursa duct join just behind pallial wall. Bursa copulatrix ovoid, medium length, broad (70%), with about 67% of length posterior to gland. Bursa duct narrow, shallowly embedded in albumen gland, about as long as bursa copulatrix. Seminal receptacle sac-like, narrow, short, overlapping proximal bursal duct.

TYPE LOCALITY.—Lifton, Ideal Beach, Bear Lake, Idaho. Holotype, ANSP 187691; paratypes, ANSP 368401.

DISTRIBUTION.—Bear Lake basin, southeastern Idaho-northeastern Utah.

DISTRIBUTION.—Ash Meadows, Amargosa River drainage.

MATERIAL EXAMINED.—USNM 850363, 850364 (topotypes).