Im looking for information on the native freshwater snails of the Los Angeles basin, is Planorbella trivolvis native?
Planorbella trivolvis is native to North America.
From my response to the direct message I got with the same question:
I don’t know if anyone has published a list of species just for the LA Basin. This is the last real comprehensive work anyone has done, but it’s for the whole continent:
https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=10004R98.TXT
Your typical native snails are going to include Planorbella, Physella, and Galba. The taxonomy for all is a bit messy and there aren’t reliable ways to differentiate species. Most are probably also easily spread by humans and may be introduced as well.
This is a good resource just for springsnails, although it looks like there may only be one known species from LA County. There could be other undiscovered species though! Any perennial spring could have an endemic species.
https://www.blm.gov/sites/blm.gov/files/documents/files/TN_449.pdf
As for Planorbella, P. trivolvis is theoretically native to California, although some people have referred to these populations as P. subcrenata (sometimes considered a subspecies of P. trivolvis). Planorbella are also often introduced, though, so there could very well be multiple species present in more developed areas. There is a large need for freshwater snail research.
Let me know if you have any other questions!
@thomaseverest, Thank you for repeating your answer here on the iNat Forum! This way, it can serve as a resource for any future readers who might have the same question.
Welcome to the iNat Forum, Ben! @amongsttheflora
In case you haven’t seen it, here is an inspiring blog post about snails of the Los Angeles Basin, from 2017: https://www.inaturalist.org/posts/12795-snails-slime-and-conservation-oh-my