A Review of the North American Freshwater Snail Genus Pyrgulopsis

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44 REMARKS.—Amongst the group of species whose penes are ornamented solely by penial, terminal, and ventral glands, this snail is distinguished by the combination of large shell without basal carina, large penis, elongate penial gland, and large caecal chamber of stomach. I have not confirmed the status of populations aside from near topotypes. MATERIAL EXAMINED.—USNM 874195, Crooked Creek, at HWY 95 crossing, Malheur County, Oregon (T 33S, R 39E, NE1/4 sec. 24)(presumed near topotypes). Pyrgulopsis isolate Hershler and Sada, 1987 Pyrgulopsis isolates Hershler and Sada, 1987:807, figs. 19d, 25, 29c, f, 33d,g, 37, 38.—USDI, 1991b:58821. DIAGNOSIS.—Shell broadly conical, medium-sized, umbilicate. Penial filament short, lobe very long, broad. Penial ornament a transverse terminal gland. DESCRIPTION.—Shell (Figure lie) broadly conical (nearly globose); height, 2.6-3.1 mm; whorls, 3.75-4.25. Early protoconch very weakly punctate, nearly smooth otherwise. Teleoconch whorls highly convex, slightly shouldered; sculpture of strong growth lines. Aperture usually slightly separated from body whorl. Inner lip complete, thickened; columellar lip sometimes slightly reflected. Outer lip orthocline to slightly opisthocline. Umbilicus rimate to perforate. Periostracum tan. Operculum (Figure 17f,g) broadly ovate, light amber except for dark, reddish area along inner edge of callus; nucleus slightly eccentric; dorsal surface weakly frilled. Attachment scar margin weakly thickened all around (more so between nucleus and mid-point of inner edge); callus weak. Central radular tooth (Figure 36d) with moderately indented dorsal edge; lateral cusps, 3-4; central cusp rounded, about as long as wide, considerably broader, slightly longer than laterals; basal cusps, 1, short, with strong dorsal support Basal process medium width; basal sockets deep. Lateral margins thickened; neck moderate. Cephalic tentacles pale or with internal gray-black patch just distal to eyespots. Snout light to dark brown-gray. Foot near pale to dark gray. Opercular lobe light, sometimes with dark internal pigment along inner edge and sides. Neck pale-light Pallial roof, visceral coil, near uniformly black. Ctenidial filaments, 21, tall, broad. Osphradium centrally positioned along ctenidial axis. Kidney opening white. Stomach caecum small. Testis, 1 whorl, broadly overlapping posterior stomach chamber. Prostate gland with large (30%) pallial section; pallial vas deferens simple. Penis (Figure 47c) large; base elongaterectangular, filament short, narrow; lobe elongate-rectangular, about as long as base, without distal taper. Terminal gland transverse, straight, elongate, borne along distal edge of lobe. Filament dark. Ovary, 1 whorl, overlapping posterior stomach chamber. Albumen gland without a pallial component Capsule gland SMITHSONIAN CONTRIBUTIONS TO ZOOLOGY longer than albumen gland. Genital aperture an elongate terminal slit with very short vestibule. Coiled oviduct a broad, near-horizontal loop well behind pallial wall. Oviduct and bursal duct join just behind pallial wall. Bursa copulatrix ovoid, medium length and width, with about 66% of length posterior to gland. Bursal duct narrow, about as long as bursa copulatrix, embedded in albumen gland. Seminal receptacle narrowly sac-like, usually folded, short, overlapping anterior bursa copulatrix. TYPE LOCALITY.—Spring south of Clay Pits, Ash Meadows, Nye County, Nevada (T 18S, R 50E, NE1/4 sec. 7). Holotype, USNM 859201; paratypes, USNM 859202, FSM 93959. DISTRIBUTION.—Endemic to type locality, Amargosa River drainage. MATERIAL EXAMINED.—USNM 850366 (topotypes). Pyrgulopsis kolobensis (Taylor, 1987), new combination Fontelicella kolobensis Taylor, 1987:19, fig. 8. Fontelicella pinetorum Taylor, 1987:20. fig. 9. DIAGNOSIS.—Shell ovate-conic, medium to large-sized, umbilicate. Penial filament short, lobe medium length. Penial ornament a short penial gland, transverse terminal gland, and usually a ventral gland. DESCRIPTION.—Shell (Figure 18a) ovate-conic; height 2.8-4.0 mm; whorls, 3.75-4.5. Earliest protoconch very weakly wrinkled, otherwise near smooth. Teleoconch whorls moderately convex, sometimes weakly shouldered; sculpture of faint growth lines. Aperture ovate, narrowly adnate or slightly separated from body whorl. Inner lip complete; columellar lip weakly reflected, sometimes thickened. Outer lip orthocline-slightly prosocline. Umbilicus rimate to perforate. Periostracum tan-brown. Operculum (Figure \Sb,c) ovate, light amber, nucleus slightly eccentric; dorsal surface smooth. Attachment scar margin a weak trace along outer edge; callus weak. Central radular tooth (Figure 36e) with well-indented dorsal edge; lateral cusps, 4-5; central cusp rounded, slightly broader and longer than laterals; basal cusps, 1, medium-sized, slightly curved, with moderate dorsal support Basal process narrow; basal sockets deep. Lateral margins thickened; neck moderate. Tentacles pale except for small pigment patch either distal to eyespot or near tip. Snout light to dark gray-brown. Foot light gray-brown; sides of opercular lobe with dark internal pigment Neck pale-moderately pigmented. Pallial roof, visceral coil moderate to dark brown-black. Ctenidial filaments, 20, medium height and width. Osphradium centered slightly posterior to middle of ctenidial axis. Kidney opening white. Stomach with medium-sized caecum. Testis, 1.5-2.0 whorls, overlapping anterior stomach chamber (sometimes to edge of style sac). Prostate gland with short pallial section; pallial vas deferens proximally kinked. Penis (Figure 47d) large; filament short tapering; lobe medium length, near-rectangular. Penial gland weak, covering only base
NUMBER 554 45 FIGURE 18.—Western Pyrgulopsis: a-c. P. kolobensis, USNM 847249 (a. shell. 3.2 mm; b,c. opercula, bar = 0.43 mm); d-g, P. longinqua (d. shell (left), USNM 526733, 3.5 mm; e. shell (right), USNM 874059, 2.3 mm; f,g, opercula, bar = 0.3 mm).
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 and 30: NUMBER 554 23 DISTRIBUTION.—This
Page 31 and 32: NUMBER 554 25 nucleus slightly ecce
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 49: NUMBER 554 FIGURE 17.—Western Pyr
Page 53 and 54: NUMBER 554 copulatrix. Seminal rece
Page 55 and 56: NUMBER 554 Pyrgulopsis merriami (Pi
Page 57 and 58: NUMBER 554 FIGURE 20.—Western Pyr
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: NUMBER 554 93 FIGURE 36.—Central
Page 101 and 102:
NUMBER 554 FIGURE 38.—Central rad
Page 103 and 104:
NUMBER 554 97 FIGURE 40.—Central
Page 105 and 106:
NUMBER 554 99 FIGURE 42.—Central
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
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A Review of the North American Freshwater Snail Genus Pyrgulopsis

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