lampeye

Saw this yesterday. I think I know what it is, but I want your opinions. In the second photo, yes, there's a Ludwigia with it, but I'm asking about the more delicate-looking light green submerged plant. I tried, but found no flowers on any plants.



The punchline is...I'm in Pennsylvania. o_0

miremonster

I'm pretty sure that this is a Callitriche species. The swimming rosette-like shoot tops are characteristic of the most species of this genus. At least here in Europe there are many difficult to distinguish Callitriche spp., I don't know the ones occuring in the U.S.

lampeye

Danke MM. I think you put me on the right track. It would almost certainly be C. palustris. It just seemed so Didiplis-esque, except for those maddening surface leaves. And I would expect to see lots of flowers in the leaf axils. The location would be ALL kinds of wrong, though. But Callitriche would make perfect sense.

Tausendblatt

WOW, now I know I am wrong as to the species of callitriche I have...

lampeye

It could be C. stagnalis, but I would need flowers or fruit to make the ID positive. There are only three aquatic Callitriche in PA, according to the only reference I have, and it does not resemble C. heterophylla.

Cavan Allen

What part of Pennsylvania?

armedbiggiet

can i find this in the market? never hear any one have these. If PA can have it MD should too.

lampeye

Southeastern PA, near Quakertown. Found some of what MIGHT be Samolus, too. This would be a good spot for a DVAGA excursion.

Cavan Allen

Thought you might be. I'm not so sure what you took a photo of is a Callitriche. Elatine americana looks astonishingly similar submersed, and I'd wager that's what you saw (endangered in PA - only found in the extreme East and Southeast according to USDA). Callitriche floating leaves are rounder and more numerous, and all species I've encountered (many in PA) are ephemeral, and only seen in the spring and early summer; it's almost guaranteed that they're gone by now. E. americana may be found as small clumps growing emersed on the shore with typical Elatine fruits; you might try looking there again for that. I contrast to Callitriche species that die every winter (not all annuals do in culture), E. americana soldiers on, unaware of the bitter cold outside your window.

lampeye

I'm hoping this might help a little more. Having seen photos of both, I'm still leaning towards Callitriche, but I have little experience with either, so...