Pyrgulopsis licina Hershler, Liu & Bradford

Hershler, Robert, Liu, Hsiu-Ping & Bradford, Corbin, 2013, Systematics of a widely distributed western North American springsnail, Pyrgulopsis micrococcus (Caenogastropoda, Hydrobiidae), with descriptions of three new congeners, ZooKeys 330, pp. 27-52 : 30-33

Pyrgulopsis licina Hershler, Liu & Bradford sp. n. Figs 3, 4 A–B

Pyrgulopsis micrococcus . - Hershler and Sada 1987 (in part).

Pyrgulopsis micrococcus clade C. - Liu et al. (2003).

Types.

Holotype, USNM 850347 (a dry shell), spring south of Clay Pits, Ash Meadows, Nye County, Nevada, 36.40719°N, 116.37856°W, 11 November 1985, R. Hershler and D. W. Sada. Paratypes, USNM 1204732 (from same lot).

Referred material.

NEVADA. Nye County: USNM 859186, USNM 903997, spring south of Clay Pits, USNM 850345, USNM 850346, USNM 850347, USNM 850348, USNM 859185, spring at Clay Pits, Ash Meadows (36.41608°N, 116.37802°W), USNM 850343, USNM 850344, USNM 859184, spring north of Clay Pits, Ash Meadows (36.41613°N, 116.37808°W), USNM 850334, Rogers Spring, Ash Meadows (36.47931°N, 116.32622°W), USNM 850336, USNM 1122742, USNM 1122754, USNM 1197782, USNM 1204745, springs south of Rogers Spring, Ash Meadows (36.47467°N, 116.32747°W), USNM 850349, USNM 1197775, spring east of Crystal Reservoir, Ash Meadows (36.40790°N, 116.31297°W), USNM 850350, spring east of Crystal Reservoir, Ash Meadows (36.40742°N, 116.31197°W), USNM 903982, spring east of Crystal Reservoir, Ash Meadows (36.40836°N, 116.31042°W), USNM 1197780, spring ca. 100 m north of Collins Ranch, Ash Meadows (36.42038°N, 116.29921°W), USNM 850352, USNM 850351, USNM 859188, USNM 859189, USNM 1122848, Frenchy Springs, Ash Meadows (36.36364°N, 116.27432°W), USNM 850353, USNM 859190, USNM 894336, USNM 1122849, Last Chance Spring, Ash Meadows (36.35700°N, 116.27400°W).

Diagnosis.

A small congener (maximum shell height, 2.4 mm) having a narrow-conic shell. Distinguished from similar regional species by its strongly curved penial filament and absence of glands on the penis. Further differentiated from frequently sympatric Pyrgulopsis sanchezi (described below) by its highly convex, deeply incised teleoconch whorls and ovate shell aperture.

Description.

Shell (Fig. 3 A–C) narrow-conic, whorls 3.75-4.50. Teleoconch whorls highly convex, sutures deeply impressed. Aperture ovate, parietal lip complete, narrowly adnate or slightly disjunct, umbilicus narrow. Outer lip thin, orthocline or prosocline. Sculpture of faint, irregular spiral striae.

Operculum (Fig. 3 D–E) as for genus; edges of last 0.5 whorl frilled on outer side; muscle attachment margins variably thickened on inner side. Radula (Fig. 3 F–H) as for genus; dorsal edge of central teeth concave, lateral cusps four–six, basal cusp one. Lateral teeth having three–four cusps on both inner and outer sides. Inner marginal teeth with 20-25 cusps, outer marginal teeth with 24-31 cusps. Radula data are from USNM 850348.

Penis (Fig. 4 A–B) medium-sized; filament medium length, narrow, weakly tapering, strongly curved (to outer side); lobe small, rectangular, horizontal or oblique; glands almost always absent (87/90 specimens), two specimens had a small, dot-like gland along the distal edge of the lobe and one specimen had a glandular smear near the distal edge of the ventral surface of the lobe. Penial data are from USNM 850334, USNM 850348, USNM 850351.

Etymology.

The epithet is an adjective derived from the New Latin licinus, meaning bent or turned upward, and refers to the distinctive shape of the penial filament in this species.

Distribution.

Ash Meadows, Amargosa River basin (M7, M29, M30, M52, M54, M58, Fig. 2). The type locality is a broad spring brook that courses through a pit-like depression (Fig. 5A).

Remarks.

The relationships of Pyrgulopsis licina were not well resolved in the molecular phylogenetic analysis (Fig. 1). Haplotype variation within this clade was relatively small (Appendix II).