Fluminicola warnerensis, Hershler & Liu & Frest & Johannes, 2007

Hershler, Robert, Liu, Hsiu-Ping, Frest, Terrence J. & Johannes, Edward J., 2007, Extensive diversification of pebblesnails (Lithoglyphidae: Fluminicola) in the upper Sacramento River basin, northwestern USA, Zoological Journal of the Linnean Society 149 (3), pp. 371-422 : 388-393

FLUMINICOLA WARNERENSIS SP. NOV. (WARNER

PEBBLESNAIL)

Type material: Holotype ( Fig. 10A ), USNM 1020652 , Parsnip Springs, south of South Warner Road (FS64, also designated as 39NO1) in wet, open meadow, Modoc National Forest , Lassen County, California

(729680 E, 4559760 N, 1957 m), 18 September 2001, TF, EJ . Paratypes (from same lot), USNM 1020653 .

Referred material: CALIFORNIA. Lassen County: USNM 1020655 , spring brook in sedge meadow on east side of Blue Lake just east of Blue Lake Campground access road, c. 0.16 km east of lake, Modoc National Forest (728375 E, 4558240 N, 1853 m), 17 September 2001 TF, EJ.— USNM 1020656 , spring creek to Blue Lake on west side of FS64, c. 0.81 km south-east of Blue Lake Campground, Modoc National Forest (729020 E, 4557760 N, 1894 m), 18 June 1994 TF, EJ. – USNM 883557 , USNM 883561 , spring tributary to Blue Lake (729770 E, 4557577 N, 1830 m), 2 June 1993 DS. – USNM 883559 , spring tributary to large meadow, Harvey Creek drainage, Jess Valley (725112 E, 4563474 N), 2 June 1993 DS. – USNM 883564 , stream tributary to south end of Blue Lake (728489 E, 4558041 N, 1830 m), 1 July 2003 DS. Modoc County: USNM 1020654 , Soup Spring just north of Soup Spring Campground, Modoc National Forest (728000 E, 4576530 N, 2067 m), 17 September 2001 TF, EJ. – USNM 1020789 , Soup Creek on north side of FS40N24 crossing, Modoc National Forest (726000 E, 4574760 N, 1702 m), 17 September 2001 TF, EJ. – USNM 1020657 , springs south-east of Hilton on south side of Hilton Road, 0.48 km west of Hilton Creek (689280 E, 4567560 N, 1769 m), 18 September 2001, TF, EJ. – USNM 1020658 , head spring of Rush Creek west of FS40N18, north-west end of Manzanita Ridge, Modoc National Forest (682590 E, 4573530 N, 1903 m), 20 July 2002 TF, EJ. – USNM 1020659 , Miller Spring run, 0.32 km south of FS41N11, Miller Gulch, Modoc National Forest (664700 E, 4577150 N, 1586 m), 22 September 2001 TF, EJ. – USNM 1020790 , springs in gulch east of Miller Gulch, 0.48 km on road off (south of) FS41N12, Modoc National Forest (667260 E, 4576920 N, 1513 m), 22 September 2001, TF, EJ .

Diagnosis: Differs from similar F. turbiniformis in its larger size (SH, SW, P = 0; data for latter given below), darker body pigment, less prominent sperm storage area in the coiled oviduct, complete overlap of the seminal receptacle by the albumen gland, broader bursa copulatrix, absence of a seminal receptacle duct, and frequent occurrence of a papilla-like capsule gland opening. Distinguished from geographically proximal F. erosus and F. lunsfordensis (both described below) by its more elongate shell, more convex shell whorls, single basal cusp of the central radular tooth, and enlarged large central cusp of the lateral radular tooth. Also differs from the former in its larger size and from the latter by its weakly angled adapical portion of the aperture.

Description: Shell ( Fig. 10A–K ; Table 4) turbiniform to ovate-conic, rarely having eroded spire; height, 2.40–4.68 mm; whorls, 3.5–4.0. Protoconch 1.4 whorls, diameter approximately 0.70 mm. Teleoconch whorls medium to weakly convex, sometimes wider below, narrowly shouldered. Last 0.125 whorl rarely disjunct. Aperture broad, angled above. Parietal lip complete, slightly disjunct and thickened in larger specimens. Columellar lip usually medium width and overlapping part of umbilical region, sometimes narrow. Outer lip usually thin, prosocline. Shell anomphalous or narrowly rimate, umbilical region sometimes excavated. Periostracum tan, light brown, or red. Last 0.5 whorl of operculum very weakly frilled ( Fig. 10L ). Central radular tooth approximately 53 µm wide, cutting edge convex, lateral cusps four (one tooth having three); central cusp pointed; basal cusps one; basal tongue Vshaped, equal to lateral margin ( Fig. 10O ). Lateral tooth face broadly rectangular; central cusp rounded, lateral cusps two (inner), three to five (outer); outer wing flexed, medium length ( Fig. 10N ). Inner marginal teeth having 20–26 cusps ( Fig. 10M, N ). Outer marginal teeth having 24–38 cusps; basal wing rectangular ( Fig. 10M ). Head-foot dark brown, almost black. Ctenidium connected to pericardium by short, efferent branchial vessel; ctenidial filaments approximately 17, without pleats. Osphradium elongate, positioned opposite middle of ctenidium. Female reproductive anatomy shown in Figure 6B . Bursa copulatrix horizontal, pyriform or triangular, duct short. Seminal receptacle medium-sized, overlapped by albumen gland. Albumen gland having pronounced rectal furrow. Capsule gland a little longer than albumen gland. Genital aperture a short slit, usually forming a small papilla. Penis medium-sized, narrow, coiled, distal end pointed ( Fig. 7B ). Base and medial section grey, pigment concentrated along penial duct. Penial duct near centrally positioned, weakly undulating in proximal section.

Distribution: Distributed within the drainage of the south fork of the Pit River, and along the Pit River just above Big Valley (upper Pit River basin) ( Fig. 9 ).

Etymology: The species name refers to the type locality area in the Warner Mountains, north-eastern California.

Remarks: Populations allocated to F. warnerensis vary somewhat in shell form ( Fig. 10A–K ). Nonetheless they share diagnostic morphological features, are little divergent genetically (0–0.6% for COI, 0–0.3% for cytb), and were consistently depicted as a well-supported monophyletic group ( Figs 2–4 ), justifying recognition as a single species. In all of the phylogenetic analyses, F. warnerensis was depicted as most closely related to F. turbiniformis , with moderate to strong bootstrap support (75–100%). Haplotypes of these two species differ by 2.3–2.6% ( COI) and 3.6–3.9% (cytb).

This species was referred to as Fluminicola n. sp. 13 by Frest & Johannes (1995a).

FLUMINICOLA LUNSFORDENSIS SP. NOV. ( LUNSFORD

Figures

Figure 2. Bayesian phylogram for cytochrome c oxidase subunit I sequences. Upper Sacramento River basin haplotypes are distributed among clades A–D. Posterior probability values ≥ 90% are shown. Upper Sacramento River basin lineages newly discovered in this study are highlighted by the larger font. Specimen codes are from Table 1.

Figure 3. Bayesian phylogram for cytochrome b sequences. Upper Sacramento River basin haplotypes are distributed among clades A–D. Posterior probability values ≥ 90% are shown. Upper Sacramento River basin lineages newly discovered in this study are highlighted by the larger font. Specimen codes are from Table 1.

Figure 4. Bayesian phylogram for the combined dataset (cytochrome c oxidase subunit I and cytochrome b). Upper Sacramento River basin haplotypes are distributed among clades A–D. Posterior probability values ≥ 90% are shown. Upper Sacramento River basin lineages newly discovered in this study are highlighted by the larger font. Specimen codes are from Table 1.

Figure 6. Female glandular oviduct and associated structures (viewed from the left side) for six species of Fluminicola. A, F. fremonti (USNM 1020661). B, F. warnerensis (USNM 1020653). C, F. erosus (USNM 1020664). D, F. favillaceus (USNM 1020670). E, F. neritoides (USNM 1020682). F, F. anserinus (USNM 1020728). Scales = 0.5 mm. Ag, albumen gland; Bu, bursa copulatrix; Cg, capsule gland; Dbu, bursal duct; Ga, genital aperture; Pc, posterior wall of pallial cavity; Rf, rectal furrow; Sr, seminal receptacle; Vc, ventral channel of capsule gland.

Figure 7. Penes (upper side) of the 13 Fluminicola species newly described herein. A, F. fremonti (USNM 1020661). B, F. warnerensis (USNM 1020653). C, F. lunsfordensis (USNM 1020689). D, F. erosus (USNM 1020664). E, F. favillaceus (USNM 1020670). F, F. caballensis (USNM 1020676). G, F. neritoides (USNM 883563). H, F. ahjumawi (USNM 1020699). I, F. umbilicatus (USNM 1020706). J, F. anserinus (USNM 1020728). K, F. potemicus (USNM 1020719). L, F. scopulinus (USNM 1020722). M, F. multifarius (USNM 883782). Scale = 0.25 mm. Pd, penial duct.

Figure 9. Map showing the distribution of eight species (plus Fluminicola sp.) in the Goose Lake and Pit River basins. Some symbols represent multiple, closely proximal localities.

Figure 10. Shells, opercula, and radula of Fluminicola warnerensis. A, holotype (USNM 1020652). B, USNM 1020654. C, USNM 1020655. D, USNM 1020656. E, 1020657. F, USNM 1020658. G, USNM 883559. H, USNM 883561. I, USNM 883564. J, USNM 1020655. K, USNM 1020653. Scales = 1.0 mm. L, outer side of operculum (USNM 1020653). Scale = 100 µm. M, portion of radular ribbon (USNM 1020653). Scale = 20 µm. N, lateral and inner marginal radular teeth (USNM 1020653). Scale = 20 µm. O, central radular teeth (USNM 1020653). Scale = 20 µm.