So I've noticed one thing about Montreal's fauna that's quite different from the upper Gatineau: extremely abundant relatively large snails. They are
Cepaea hortensis (white-lipped snail) and
Cepaea nemoralis (grove snail).
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Cepaea hortensis - notice that the shell margin at the lip of the shell is pale |
Both species are native to Europe and have been introduced in North America. I have found their abundance here in Montreal quite striking, as until coming here I had never seen snails of this size anywhere I had been in Quebec or Ontario.
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Cepaea hortensis |
Like most gastropods, this species are both hermaphrodites (but still have to mate with others to produce viable eggs). They are also among the species which produce a "love dart" -- essentially a sperm-filled spike that is shot into the body of another snail during mating. This dart actually does pierce the body of the other snail. Violent! ... Reproduction can be a very strange process indeed.
Distinguishing the two closely-related species without dissecting them is not 100% accurate -- while generally
Cepaea hortensis has a white or yellow lip to its shell and
Cepaea nemoralis has a brown lip, this isn't a perfect correspondence, so it is possible (but unlikely) that these individuals are misidentified.
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Cepeaea nemoralis - notice that the shell margin at the lip (opening) is brown |
Aside from the lip colour difference, both species show quite a lot of shell pattern polymorphism, varying in base shade from a pale creamy colour to a richer yellow, and having a variable number of brown stripes.
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