Family Punctidae

Paralaoma servilis (Shuttleworth, 1852): Pinhead Spot

  Records.— Map 12. RGF: 95-110-3096, 95-133-3197.

In British Columbia Paralaoma servilis is most often seen at disturbed, open sites during the wetter months of the year. In the upper Fraser Basin, this species was collected from under aspen logs at two localities, both with somewhat modified habitat, at elevations of 690 m and 760 m a.s.l.

Although this species has an inclination to be synanthropic, it appears to be native to northwestern North America. Among the plethora of synonymous names applied to this widespread, almost cosmopolitan species are Punctum conspectum (Bland, 1865), Punctum (or Toltecia) pusilla (Lowe, 1831), and Paralaoma caputspinulae (Reeve, 1852) (see Falkner et al. 2002 and references therein).

Punctum randolphii (Dall, 1895): Conical Spot

  Records. — Map 13. RBCM: 001-00250-010, 001-00265-005, 002-00152-002.

Figure 6 Punctum randolphii. A Specimen from Bone Creek, North Thompson River (outside of the upper Fraser drainage) (RBCM 001-00278-002).

In the upper Fraser Basin, this species was living in leaf litter  in a cottonwood stand, an open mixed-wood forest, and a grove of trembling aspen; the elevational range of the three sites is 820–1220 m a.s.l. Elsewhere in B.C., the species has been found from sea level to about 1700 m a.s.l.

Recent collections made in 2001–2002, but outside the geographic limits of this report, suggest that the species is common in the Quesnel and Shuswap Highlands and along the North Thompson River valley. It may be more infrequent on the eastern margin of the Interior Plateau and appears absent from a large area of the Interior Plateau. P. randolphii is also recorded from the Kootenays, the Skeena and Hazelton mountains (Forsyth 2001a), the Queen Charlotte Islands (Forsyth collection), the north coast (RBCM collection) and from many localities on the south coast.

Compared to coastal British Columbia examples, most interior specimens (Figure 6) are generally a little smaller, but shell size and the relative height to width is variable both in coastal and interior examples. Punctum randolphii looks to be much more variable in form and size than most literature on these snails (e.g., Pilsbry 1946) would suggest.

Although a single, large shell reported earlier from the Columbia Basin was tentatively called P. californicum Pilsbry, 1898 (Forsyth 1999), I now consider this and all British Columbia material as belonging to one variable species for which I use the name P. randolphii. However, the issue is further complicated because Alberta snails are usually identified as P. minutissimum (Lea, 1841), because they occur east of the Continental Divide.

Family Discidae

Discus shimekii (Pilsbry, 1890): Striate Disc

  Records. — Map 14; “around Lake Tetana” (Stanwell-Fletcher & Stanwell-Fletcher 1943).

This species is included here on the grounds that Stanwell-Fletcher & Stanwell-Fletcher (1943:36) recorded it from Tetana Lake on the Driftwood River (ca 55°55´N, 126°37´W). Except for Discus shimekii, they did not list other species of terrestrial molluscs in brief observations on the common insects and a few other invertebrates that they collected around the lake. Any material, if it existed, would be expected to be in the RBCM, but I have not found it, and the record cannot be verified. In British Columbia, D. shimekii occurs along the Rocky Mountains, in the Peace River region and west to the Haynes Triangle.

Discus whitneyi (Newcomb, 1864): Forest Disc

  Records. — Map 15. RBCM: 001-00249-009, 001-00296-002, 001-00337-005, 001-00338-001, 001-00339-003, 001-00222-001, 001-00225-003, 001-00228-003, 001-00230-001, 001-00233-004, 001-00241-002, 001-00242-001, 001-00243-002, 001-00264-001, 001-00265-003, 001-00267-003, 001-00268-001, 001-00277-003, 001-00291-004, 001-00294-001, 001-00312-001, 001-00332-004, 001-00334-004, 001-00335-003, 999-00148-001. RGF: 01-007-4872, 95-133-3198, 95-134-3195, 97-121-1203, 97-164-1499, 97-173-1514, 97-175-1354, 97-176-1383, 97-177-1381, 97-179-1365, 97-180-1378, 97-181-1370, 97-182-1351, 98-023-1607, 98-024-1608, 99-046-4621. CMN: 83081.

Discus whitneyi is one of the most common and widespread land snails in the upper Fraser Basin and in British Columbia as a whole, except along the coast. In the upper Fraser Basin, only Euconulus fulvus appears more ubiquitous. D. whitneyi lives in forests and at open sites, under fallen branches, logs, stones, debris and in leaf litter; in the upper Fraser Basin it has been found at elevations between 470–1220 m a.s.l.

Family Euconulidae

Euconulus fulvus(Müller, 1774) : Brown Hive

  Records. — Map 16. RBCM: 001-00222-002, 001-00225-001, 001-00226-001, 001-00228-002, 001-00229-002, 001-00230-003, 001-00231-001, 001-00232-001, 001-00233-002, 001-00235-001, 001-00236-001, 001-00237-001, 001-00241-001, 001-00245-002, 001-00249-011, 001-00250-009, 001-00251-001, 001-00255-008, 001-00264-002, 001-00265-002, 001-00266-004, 001-00293-005, 001-00294-002, 001-00296-004, 001-00332-006, 001-00336-001, 001-00337-003, 001-00338-005, 001-00339-004. RGF: 01-007-4874, 03-093-5190, 95-133-3199, 95-134-3196, 97-164-1498, 97-175-1353, 97-177-1379, 97-179-1362, 97-184-1371, 97-193-2012, 98-046-228. CMN: 2859, 83141.

Euconulus fulvus is perhaps the most common species in the upper Fraser Basin and northern B.C. and is a generalist, living in mesic to dry sites, both in forests and non-forested habitats. It occurs under dead wood, leaf litter, stones and vegetation, and it lives in leaf litter. E. fulvus is one of species most often found at or near the treeline. In the upper Fraser Basin, this species was found at elevations up to 2100 m a.s.l.

Euconulus praticola (Reinhardt, 1883): Marsh Hive

  Records. — Map 17. RBCM: 001-00254-006. RGF: 95-111-3097.

While the majority of Euconulus in collections are attributable to Euconulus fulvus, there appears to be a second species that is identifiable by shell characters, body colour, and habitat preference. In British Columbia examples, E. praticola differs from E. fulvus by having a reddish rather than yellowish shell and shining rather than silken microsculpture on the apical surfaces of the whorls; the microsculpture on the base of the shell in E. praticola has relatively deeper spiral striae and stronger axial grooves than E. fulvus. The basal shell surface of E. fulvus varies among British Columbia material; some have the base almost without any microsculpture, while others have clear but relatively shallower spiral striae than E. praticola. There are also usually some irregularly spaced axial grooves present in B.C. examples of E. praticola, which are seldom ever as well developed in the other species. Animals of E. praticola are black throughout, including the mantle, whereas the body of E. fulvus is variously light to dark grey (paler on the sides of the foot) with the mantle spotted with black.

Some authors have used the name Euconulus alderi (Gray in Turton, 1840) for the wetland species in Ontario and the U.S. Midwest (e.g., Grimm 1996; Nekola 2001; Nekola & Massart 2001), as has been done in Europe (e.g., Kerney and Cameron 1979). However, Falkner et al. (2002) recently treated E. alderi as a synonym of E. trochiformis (Montagu, 1803), a forest-dwelling species, and resurrected the name E. praticola for the dark-bodied wetland species in Europe.

It is surprising that this wetland species has only recently been recognized in North America, as it seems to be quite distinct. However, wetland habitats are generally under-investigated for terrestrial gastropods, and the acceptance of a wetland congener to E. fulvus has been controversial, even in Europe. For example, Schileyko (2002) stated that there was probably only one variable Holarctic species despite several decades of literature stating otherwise.

In addition to two records from the upper Fraser Basin, there are nine additional unpublished B.C. localities: two in the Bulkley Valley near Telkwa (Forsyth collection), four from the Columbia Basin (RBCM 998-00273-00-3, 998-00282-005, 998-00264-008, 998-00285-004**), and three from Greater Vancouver and the lower Fraser Valley (Forsyth collection).

Unlike Euconulus fulvus, E. praticola is found only at wet sites: marshes, forested floodplains and grassy shorelines of waterways. Elevations of the known sites range from sea level to 760 m a.s.l.; in the upper Fraser Basin, both known localities are at ca 760 m a.s.l. The two species of Euconulus were not sympatric at any of these localities. E. praticola is often found along with characteristically wetland species such as Vertigo ovata, Zonitoides nitidus, various unidentified species of succineids, and amphibious lymnaeids.

Family Gastrodontidae

Zonitoides arboreus (Say, 1816): Quick Gloss

  Records. —Map 18. RBCM: 001-00225-002, 001-00226-002, 001-00228-004, 001-00229-001, 001-00237-002, 001-00242-004, 001-00243-001, 001-00245-003, 001-00249-010, 001-00251-002, 001-00255-007, 001-00266-002, 001-00267-002, 001-00268-002, 001-00274-002, 001-00277-005, 001-00284-002, 001-00292-001, 001-00293-004, 001-00294-004, 001-00296-003, 001-00312-002, 001-00332-005, 001-00335-005, 998-00054-001. RGF: 01-007-4873, 01-009-4877, 01-010-4878, 95-058-2747, 97-175-1356, 97-176-1430, 97-177-1382, 98-046-1660. CMN: 83080.

Zonitoides arboreus is widespread and common in northern British Columbia, often found along with Discus whitneyi and Euconulus fulvus in coniferous, mixed-wood and deciduous forests. It is typical of dry to mesic forests in the upper Fraser Basin, but also has occasionally been found along the margins of water bodies. In the upper Fraser Basin this species has been found at elevations between 460 m and 1040 m a.s.l.

Family Daudebardiidae

Nesovitrea binneyana (Morse, 1864): Blue Glass

  Records. — Map 19. RBCM: 001-00249-013, 001-00255-006, 001-00337-004, 001-00338-002, 001-00236-002, 001-00245-001, 001-00264-004, 001-00266-003, 001-00276-002, 001-00277-004, 001-00291-002, 001-00293-003, 001-00335-006, 002-00153-001. RGF: 97-175-1355, 97-176-1368, 97-179-1367.

This species is widespread across B.C., where it is found mostly in mesic deciduous or mixed-wood forests. Occasionally it is found in open or forb-covered, disturbed ground. In the upper Fraser Basin, Nesovitrea binneyana was collected at 460–1120 m a.s.l.

Nesovitrea electrina (Gould, 1841): Amber Glass

  Records. — Map 20. RBCM:  001-00233-003.

Nesovitrea electrina is widespread in B.C. but is less frequently encountered as the previous species. In the upper Fraser Basin, it was found only at McBride, where it was in cottonwood woods along the Fraser River.

Family Vitrinidae

Vitrina pellucida (Müller, 1774): Western Glass-snail

  Records. — Map 21. RBCM: 001-00225-005, 001-00250-008, 001-00253-007, 001-00255-009, 001-00264-005, 001-00265-001, 001-00266-001, 001-00268-005, 001-00277-001, 001-00291-001, 001-00332-003, 001-00334-003, 001-00336-003, 001-00337-007, 002-0071-002. RGF: 95-133-3200; 97-179-1363; 98-024-1610. CMN: 83140, 93333.

Vitrina pellucida occurs across the Palearctic and is widespread in western North America where it often goes by the synonym V. alaskana Dall 1905. All material collected in July 2001 fieldwork was either juvenile or were empty shells only, but dissections of snails from Dreyskull (ca 4 km N of Glendale; CMN 93333) and the Hazelton Mountains (Forsyth collection) show that the vas deferens is enclosed in a penial sheath. In this regard, their genital anatomy conforms to that of V. pellucida, as described by Forcart (1955; see also Bequaert & Miller 1973, Roth & Lindberg 1981, and Roth & Sadeghian 2003). This species is common and widespread throughout British Columbia, living in a wide variety of habitats that are often seasonally dry.

In the upper Fraser Basin, Vitrina pellucida the localities where it was found are between 660 m and 1220 m a.s.l., and all were below tree line. However, no alpine or subalpine habitat was surveyed in the upper Fraser Basin; elsewhere in B.C., V. pellucida has been located above 1220 m. For example, this species was living at 1740 m in the alpine tundra on Hudson Bay Mountain near Smithers (Forsyth collection).

Family Limacidae

Limax maximus Linnaeus, 1758: Giant Gardenslug

  Records. — Map 22. RBCM: 001-00335-007.

Limax maximus is an introduced western European slug, now widespread in southern British Columbia (Rollo & Wellington 1975; Forsyth 2004; RBCM collection). In the upper Fraser Basin, this species was collected a roadside park in Quesnel. Additional searches in urban areas probably would turned further records.

Family Agriolimacidae

Deroceras laeve (Müller, 1774): Meadow Slug

  Records. — Map 23. RBCM: 001-00254-007; 001-00274-001; 001-00332-002; 001-00334-001. CMN: 83142.

In the upper Fraser Basin Deroceras laeve was found along the shorelines of waterways and permanently wet forested sites. At Teardrop Lake (RBCM 001-00074-001) slugs were found under logs in a site that was clear-cut in 1985 and burnt in 1986; major vegetation consisted of willows and young conifers. Localities in the upper Fraser Basin are at elevations between 760 m and 880 m a.s.l.

This is one of the most widespread species of slugs in the world, occurring on all continents except Antarctica (Wiktor 2000). Although introduced to many parts of the world, it is apparently, at least in part, native to North America. There is no evidence to suggest that the species is not native in the upper Fraser Basin, where it occurs in both disturbed and undisturbed habitats.

Deroceras reticulatum (Müller, 1774): Grey Fieldslug

  Records. — Map 24. RBCM: 001-00243-003, 001-00253-009, 001-00293-007, 001-00331-001. CMN: 93332, 93333, 93339, 93342.

In the upper Fraser Basin Deroceras reticulatum was found at an abandoned farm site, roadside highway pullouts, and a provincial park. This European slug is widely introduced into British Columbia and likely is a common synanthrope in the upper Fraser Basin.

Family Arionidae

Arion circumscriptus Johnston, 1828: Brown-banded Arion

  Records. — Map 25. RBCM: 001-00241-004, 001-00331-002.

In the upper Fraser Basin, and around Canim Lake (outside the scope of this report), the introduced European slug Arion circumscriptus was found in disturbed habitats and coniferous and mixed-wood forests immediately adjacent to roads. Elsewhere in British Columbia, this species is recorded from Greater Vancouver (Rollo & Wellington 1975), southern Vancouver Island, the Queen Charlotte Islands, and the Bulkley Valley at Smithers (RBCM collection).

This species was recognized from other species of Arion by having a false keel (present in the subgenus Carinarion) and the presence of black pigment spots on the mantle. These spots are believed to be a reliable character for distinguishing A. circumscriptus from other Carinarion [A. fasciatus (Nilsson, 1823); A. silvaticus Lohmander, 1937]. However, one animal was found at Hwy 16 near the Goat River (RBCM 001-00296-001) that when alive had bright orange-yellow lateral bands, suggestive of Arion fasciatus (Nilsson, 1823), but the dissection of this slug showed that it was juvenile—the genitalia were undeveloped—and therefore not identifiable with certainty (H. Reise, pers. comm.). Arion fasciatus, A. silvaticus and A. circumscriptus form a group (subgenus Carinarion) of very similar species that are at best only weakly distinguishable by external pigmentation; a recent study has further determined that diet can influence body pigmentation in these species (Jordaens et al. 2001). Thus, the strongly yellow-orange pigmentation of this individual is not conclusive.

There seems to be no anatomically verified records of Arion fasciatus from British Columbia, although records of “A. fasciatus” were cited in some older literature and most (or all) are probably misidentifications of A. circumscriptus.

Arion subfuscus (Draparnaud, 1805): Dusky Arion

  Records. — Map 26. RBCM: 002-00142-001.

Arion subfuscus is another introduced Eur-opean slug in the upper Fraser Basin. Although there is only one record of it from the area (in the campground at Ten Mile Lake Provincial Park), this species is likely both widespread and common. Elsewhere in northern British Columbia A. subfuscus is known from the Bulkley Valley, the Queen Charlotte Islands and Alice Arm (unpublished records, RBCM).

Prophysaon andersonii (Cooper, 1872):Reticulate Taildropper

  Records. — Map 27. RBCM: 001-00243-004, 001-00253-008, 001-00254-008, 001-00264-006, 001-00293-006, 001-00332-001,001-00333-001, 001-00337-001. CMN: 93338, 93340.

In the upper Fraser Basin, this species was found in open, mixed-wood forests and pure stands of trembling aspen (at 670–970 m a.s.l.) where it was usually found under logs or openly crawling. This species and Deroceras laeve are the only native species of slugs in the upper Fraser Basin.

Terrestrial Gastropods ...   
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