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Discus whitneyi, Tyhee Lake

Discus whitneyi, Tyhee Lake, near Telkwa, BC.

Online database: Bibliography of the Terrestrial Molluscs of Canada

News and General Information

Wanted: leaf litter samples from anywhere in Canada
While the minute land molluscs that dwell in leaf litter are a major component of the terrestrial mollusc fauna of Canada, they have historically been neglected in many parts of Canada. Their small size has usually meant that they have been overlooked by all but the most dedicated naturalists and malacologists. Many gaps in our knowledge of these animals is the direct result of insufficient collections from almost all regions of the country. I am looking for donations of leaf litter samples (each 1–2 L in volume), or drift samples containing terrestrial species from anywhere in Canada. More information here.

Interactive maps at E-Fauna BC
October 2011 — New and updated data have been uploaded to E-Fauna BC, the Electronic Atlas of the Wildlife of British Columbia. Records are now available for terrestrial gastropods.

Need a mollusc identified?
Do you require identifications made of land snails or slugs? I can do these from specimens, or often from photographs. Please contact me for more information. I frequently help photographers, naturalists and others identify slugs and snails in their photos — just ask! Contact me here.

Latest Post

Strobilops aeneus in Canada

New publication on a rare species

In a recent publication in Check List, two new records of the small and rare land snail, Strobilops aeneus we (Mike Oldham and myself) recorded from Ontario. Here’s the background on the circumstances that lead to the publication.

Strobilops aeneus

Strobilops aeneus

In the fall of 2012, I travelled to Ottawa (and Gatineau) to study the Canadian Museum of Nature’s (CMN) mollusc collection, having received a research grant from the Malacological Society of London. I had arranged for 10 days at the CMN, so my time spanned a weekend during which I had no access to the museum. This weekend, as well as some evenings during the week, gave me an excellent opportunity to do some fieldwork around Ottawa, both on the Ontario and Québec sides of the Ottawa River (rivière des Outaouais). Twenty sites were visited, some more extensively collected than others.

Among the groups of snails that were found were Strobilops spp. This genus fascinates me because there is nothing like it out here in the West, and indeed, there’s nothing else like it in the east either. Strobilops belongs to the family Strobilopsidae and is orthurethran (related to such taxa Pupillidae, Valloniidae, and others). Strobilops has remarkably completely formed internal “barriers” inside their shells. What’s different about this group from other small native North American orthurethran land snails is that these barriers are present in immature shells as well. (I can only think of one snail in Canada, Lauria cylindracea, with internal “barriers” in immature shells, but it isn’t native.

Anyway, among the twenty sites visited was Morris Island Conservation Area, on the shore of the Ottawa River, north of Ottawa. There, a single specimen of Strobilops aeneus was found that prompted me to investigate the the species’ occurrence in Canada. My new record, as well as a collection made by Mike Oldham in southwestern Ontario, are the only records for this species from Ontario since 1941!

We also investigated claims that the species was found in Nova Scotia and cave infill in Québec. While we couldn’t confirm the Québec record, we did find that the Nova Scotia record was based on a specimen of Strobilops labyrinthicus.

You can see nicely done photos of living snails at Aydin Örstan’s blog.

Further reading …

  • Forsyth, R. G., & M. J. Oldham. 2014. Distribution of Strobilops aeneus Pilsbry, 1926, in Canada, with two new Ontario records (Mollusca: Gastropoda: Strobilopsidae). Check List 10 (2): 397–401. → URL: http://www.checklist.org.br/getpdf?NGD001-14