I recall that Nerite snails require brackish water to reproduce, but I'm not entirely sure, so please correct me if I'm wrong. Regardless, it's still possible that the snail hitched a ride on the Crypt or another plant.
If you're lucky, it might be one of the harmless and beneficial small species, like a pond, bladder, or Malaysian Trumpet snail. The pond and bladder snails are similar in shape and lay eggs, while the Malaysian Trumpet snail is long, shaped like a cornucopia, and live-bearing - I've got thousands of those in my tanks.
These small snails are great at cleaning up organics, breaking them down for the bacteria to process, and keeping the biofilms clean. They'll even eat algae, although they can't handle problem algae. They're a real asset to have in your tank, helping to keep things balanced and clean.
What's your experience with crypto?
Re: What's your experience with crypto?
Thanks boomer, appreciate the insight. Nerites not reproducing in freshwater makes sense. No eggs in sight yet, but they're still young. Curious to see how this little guy develops. If it turns out to be a species with long antennae, it's outta here - don't want to tempt my Betta. Next on the agenda: wrapping up that DIY hood for the other tank and getting it cycled.