manini

Not too sure if this should go to the plant ID or here. Anyway, L. repens 'rubin' or another hybrid. Possible cross with palustris? Possibly variants due to environmental conditions. These grow slower than your normal Ludwigia species but holds its color very well. Grown in low,med,and high light conditions without turning green. Intense red color shown best under high light.

Submerge photos (leaves are much more narrow than repens)



Emerged (again, more narrow and color difference)

THHNguyen

It's a very nice strain whatever it is. I think that L. repens 'Rubin' has 1 leaf per node.

anubias6439

Looks beautiful! Id switch out my repens x arcuata for that. Looks the same as Rotala marcranda but ludwiga

miremonster

Really beautiful! Where did You get it? Was there any trade name?
On the plant I know as 'Rubin' I never found ripe fruits. Leaves opposite as well as alternate, often on the same stem.
Do the flowers have petals?

manini

These plants came from asia. From which country exactly? Not too sure. What I understand is that they were from a friend of a friend. As far as trade name, they were calling it Ludwigia species red. Very generic. I swear that I did see petals on them before but I checked back and found none. I am hoping to see if I can get a photo of them with petals and will post them up. Do you have photos of your 'rubin'? I hope you do so that I can compare these specimens.

miremonster

OK, thank You; I'll look after my "Rubin" pics and post them.
Petals => at least it's not Ludwigia palustris. But this "Ludwigia species red" likely belongs to the same Ludwigia section (Dantia = Isnardia) because of its opposite leaves. The species and hybrids of Sect. Dantia are originally native of the Americas only.

Cavan Allen

According to Peng et al, L. palustris is most likely native to Eurasia, being "present in several widely separated areas of Europe as early as 1666." It may have dispersed to Europe in the recent past, but is not likely introduced. See:

Peng, et al (2005). Systematics and Evolution of Ludwigia Section Dantia (Onagraceae). Annals of the Missouri Botanical Garden , 92, 307-359.

As far as I know, that is still available for free online, though you do have to jump through some virtual hoops to get it. I'll come back with the link/instructions for anyone interested. It's really very good.

As far as the plant in question here goes, I do remember seeing a photo of a flowering specimen with petals. It really looks more like L. palustris otherwise, so I'm not sure what to say. Isn't the 'Rubin' supposed to be originally from Central America? The given range of L. repens doesn't extend any farther south that central Mexico. I suppose it could be a hybrid, perhaps between L. palustris and something else. With some good specimens and perhaps fresh material, I should be able to get an answer eventually.

miremonster

Thank You; I forgot that also in German floras Ludwigia palustris is listed as native: http://www.floraweb.de/pflanzenarten...l?suchnr=3517&

As for the Ludwigia 'Rubin', Claus Christensen once told me that he had seen this plant in Texas. I'll ask him again if he is sure.

Cavan Allen

Knowing its origin would really help. I remember seeing mention that it is related to L. glandulosa somehow, but it would have to be from the US for that to be, I'd think; members of section Microcarpium (including L. glandulosa) are almost entirely limited to the US, with a few in the Bahamas, Canada and Mexico (one place as a disjunct population).

We have a plant that HeyPK collected in Mississippi that really looks like a cross between L. glandulosa and L. palustris. It has opposite leaves, which is somewhat surprising since intersectional hybrids are supposed to - usually at least - have alternate leaves. Different parental combinations could produce opposite-leaved plants? Rubin may be a cross with another Ludwigia entirely? ???

Error

I keep wondering about the cladistics of Ludwigia.

Something seems extremely variable about many of them. L. inclinata in its myriad incarnations for example.

I know very little about hybrids. I feel like a cross between, say, (L. repens and L. palustris) crossed again with (L. palustris) might create something that looks like that. I am certain that it is a part of this 'Dantia' group, leastaways.

Taxonomy is fun! SOMEONE SEQUENCE THE GENES AND GIVE US AN ANSWER!

Cavan, you should PM me some links to these articles and annals you post. I would like to know more.