A Review of the North American Freshwater Snail Genus Pyrgulopsis

More documents

Recommendations

Info

24 SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY FIGURE 10.—Western Pyrgulopsis: a-c, P. bruneauensis (a, holotype, USNM 860507, 2.5 mm; bjc, opercula, USNM 860508, bars = 0.35 mm, 0.38 mm); d-f, P. bryantwalkeri, USNM 874305 (d, shell, USNM 874305,2.4 mm; e.f, opercula, USNM 858278, bar = 0.27 mm); g-i, P. californiensis, SBMNH uncat (g, shell, 3.0 mm; h,i, opercula, bar = 0.38 mm).
NUMBER 554 25 nucleus slightly eccentric; dorsal surface frilled. Attachment scar margin weakly thickened all around; callus weak. Central radular tooth (Figure 33d) with strongly indented dorsal edge; lateral cusps, 7; central cusp pointed, considerably broader and longer than laterals; basal cusps, 1, medium-sized, with slight dorsal support. Basal process moderately broad; basal sockets deep. Lateral margins unthickened; neck weak. Cephalic tentacles pale or light brown, with prominent dark internal pigment patch just distal to eyespots. Snout light to dark gray-black. Foot lightly pigmented except for occasional dark cover along anterior and posterior edges. Opercular lobe with dark internal pigment on sides and sometimes a dark patch along anterior edge. Neck pale to with heavy cover of internal black granules. Pallial roof, visceral coil, near-uniform black. Ctenidial filaments, 18, tall, medium width. Osphradium near centrally positioned along ctenidial axis. Kidney opening white. Stomach with small triangular caecum. Testis, 1 whorl, overlapping posterior stomach chamber. Prostate gland sub-circular, thin-walled, positioned entirely behind pallial wall. Pallial vas deferens without proximal kink. Penis (Figure 44d) medium-sized, narrow; filament short, narrow; lobe very short to virtually absent. Terminal gland small, circular, positioned along distal edge of lobe (often absent). Filament darkly pigmented internally. Ovary, 1 whorl, overlapping posterior stomach chamber. Pallial albumen gland large (33%). Capsule gland shorter than albumen gland. Genital aperture a terminal slit with vestibule. Coiled oviduct a broad horizontal loop. Oviduct and bursal duct join anterior to oviduct coil behind pallial wall. Bursa copulatrix ovoid, short (33%), medium width (50%), with only about 20% of length posterior to albumen gland. Bursal duct narrow, shallowly embedded in albumen gland proximally, about as long as bursa copulatrix. Seminal receptacle a very small (20%), bud-like sac overlapping anterior bursa copulatrix, positioned near ventral edge of albumen gland. TYPE LOCALITY.—A spring in the Cortez foot-hills, Humboldt Valley, Elko County, Nevada. Walker (1916:2) indicated that the general area surveyed was "about the town of Carlin." Neither Walker's account, nor other papers arising from the 1912 Walker-Newcomb Expedition in Northeastern Nevada (Pearse, 1914; Ruthven and Gaige, 1915) permits precise location of the type locality. Note, however, that Warm Spring, a prominent site located just outside of Carlin, harbors a population of snails conforming to type material in shell features and could represent the type locality. Walker (1916) indicated that syntypes were distributed to both the UMMZ and ANSP; UMMZ 118012, labeled "type," and closely conforming to the original description and illustration, is herein selected as the lectotype. Paralectotypes, ANSP 115948, MCZ 31450. DISTRIBUTION.—Only a single population is known from Humboldt River basin, northeastern Nevada. REMARKS.—Among the group of species sharing a penis ornamented solely with a terminal gland, P. bryantwalkeri is distinguished by its subcentral operculum nucleus, position of testis behind the stomach, simple pallial vas deferens, and short seminal receptacle. This species is renamed in honor of its describer, Bryant Walker. MATERIAL EXAMINED.—USNM 858278, Warm Spring, Elko County, Nevada (T 32N, R 52E, SW1/4 sec. 5). Pyrgulopsis calif orniensis (Gregg and Taylor, 1965) Bythinella binneyi.—OrcM and Dall, 1885:541. Bythinella intermedia.—Orcutt and Dall, 1885:541. Paludestrina longinqua.—Pilsbry, 1899:122 [in pan].—Steams, 1901:285 [in part].—Hannibal, 1912a:34 [in part].—Berry, 1922:99 [in part]. Amnicola stearnsiana.—Berry, 1948:59. Fontelicella californiensis Gregg and Taylor, 1965:109.—Taylor, 1975:50; 1981:152.—Burch, 1982:26, fig. 229.—Turgeon et al., 1988:61. Pyrgulopsis californiensis.—Hershler and Thompson, 1987, figs. 6, 32, 34. DIAGNOSIS.—Shell elongate-conic, medium to large-sized. Penial lobe and filament elongate. Penial ornament an elongate penial gland; transverse-elongate Dgl; elongate Dg2; Dg3 borne on weak lobule; large, curved, transverse terminal gland, and several ventral glands. Dorsal glands sometimes fused. DESCRIPTION.—Shell (Figure lOg) elongate-conic; height, 3-4 mm; whorls, 4-5. Protoconch weakly punctate, with adapical spiral lines on later portion. Teleoconch whorls moderately convex, shouldered; sculpture of fine growth lines. Aperture ovate, slightly angled above. Inner lip complete, adnate to widely separated from body whorl, medium thickness; columellar lip often reflected. Outer lip thin to moderately thick, often gently sinuate, orthocline to slightly prosocline. Umbilicus rimate to narrowly open. Periostracum brown-black. Operculum (Figure \0h,i) ellipsoidal, light amber, nucleus slightly eccentric; dorsal surface very weakly frilled. Attachment scar margin broadly thickened almost all around; callus weak. Central radular tooth (Figure 33e) with moderately indented dorsal edge; lateral cusps, 4; central cusp rounded, considerably broader and longer than laterals; basal cusps, 1, large, with weak dorsal support. Basal process narrow; basal sockets deep. Lateral margins thickened; neck moderate. Snout, foot, neck varying from pale to dark brown-black. Cephalic tentacles usually pale, sometimes with small pigment patches near mid-length. Opercular lobe pale or with dark pigment patch along anterior edge. Pallial roof usually dark; visceral coil moderate-dark, especially dark over gonads. Ctenidial filaments, 22, medium height and width. Osphradium short, positioned centrally or slightly posterior to ctenidial axis. Kidney opening thickened, sometimes white. Caecal chamber of stomach small, triangular. Testis, 1.5 whorls, overlapping posterior stomach. Prostate gland with short pallial section; pallial vas deferens proximally kinked. Penis (Figures 2a-d, 44e) large, extending well beyond mantle edge; filament slightly shorter than base, broad proximally, strongly tapered distally; lobe slightly shorter than filament, broad, expanded distally. Penial gland extending
Page 1 and 2: A Review of the North American Fres
Page 3 and 4: S M I T H S O N I A N C O N T R I B
Page 5 and 6: Contents Page Introduction 1 Materi
Page 7 and 8: A Review of the North American Fres
Page 9 and 10: NUMBER 554 position of coiled ovidu
Page 11 and 12: NUMBER 554 field work and laborator
Page 13 and 14: NUMBER 554 FIGURE 2.—Morphology o
Page 15 and 16: NUMBER 554 Sr Ag Dsr FIGURE 4.—Di
Page 17 and 18: NUMBER 554 11 studied the anatomy o
Page 19 and 20: NUMBER 554 13 contrasted the genus
Page 21 and 22: NUMBER 554 15 FIGURE 7.—Western P
Page 23 and 24: NUMBER 554 17 Pyrgulopsis amargosae
Page 25 and 26: NUMBER 554 19 (in T 3S, R 22E, 25,0
Page 27 and 28: NUMBER 554 21 Pratt (1977) recorded
Page 29: NUMBER 554 23 DISTRIBUTION.—This
Page 33 and 34: NUMBER 554 27 FIGURE 11.—Western
Page 39 and 40: NUMBER 554 33 ornament an elongate,
Page 41 and 42: NUMBER 554 35 dium centered slightl
Page 43 and 44: NUMBER 554 FIGURE 15.—Western Pyr
Page 45 and 46: NUMBER 554 Pyrgulopsis glandulosa H
Page 47 and 48: NUMBER 554 41 visceral coil black.
Page 53 and 54: NUMBER 554 copulatrix. Seminal rece
Page 55 and 56: NUMBER 554 Pyrgulopsis merriami (Pi
Page 59 and 60: NUMBER 554 or lightly pigmented on
Page 61 and 62: NUMBER 554 weakly frilled. Attachme
Page 63 and 64: NUMBER 554 lake have not yielded li
Page 65 and 66: NUMBER 554 59 REMARKS.—The small
Page 69 and 70: NUMBER 554 63 units; Dg3 small (som
Page 71 and 72: NUMBER 554 65 Pyrgulopsis simplex H
Page 75 and 76: NUMBER 554 69 DIAGNOSIS.—Shell ov
Page 77 and 78: NUMBER 554 71 filament, extending s
Page 79 and 80: NUMBER 554 FIGURE 28.—Eastern Pyr
Page 81 and 82:
NUMBER 554 75 medium length, obliqu
Page 83 and 84:
NUMBER 554 77 2e). Visceral coil li
Page 85 and 86:
NUMBER 554 FIGURE 30.—Eastern Pyr
Page 87 and 88:
NUMBER 554 ANSP 61606; paralectotyp
Page 89 and 90:
NUMBER 554 83 and southeastern Ariz
Page 91 and 92:
Appendix 2 Fossil Species Described
Page 93 and 94:
NUMBER 554 87 Pyrgulopsis bryantwal
Page 95 and 96:
NUMBER 554 89 FIGURE 32.—Central
Page 97 and 98:
NUMBER 554 FIGURE 34.—Central rad
Page 99 and 100:
Page 101 and 102:
NUMBER 554 FIGURE 38.—Central rad
Page 103 and 104:
Page 105 and 106:
Page 107 and 108:
NUMBER 554 FIGURE 44.—Penes of we
Page 109 and 110:
Page 111 and 112:
Page 113 and 114:
Page 115 and 116:
NUMBER 554 FIGURE 52.—Penes of ea
Page 117 and 118:
Abbott, R.T. 1948. A Potential Snai
Page 119 and 120:
NUMBER 554 Society of Washington, 1
Page 121:
NUMBER 554 115 gyrus, Gabbia, Hydro
show all

A Review of the North American Freshwater Snail Genus Pyrgulopsis

Create successful ePaper yourself

Delete template?

Save as template?