I am still having problems with this change on the heuffelii.
Wish I could find the article I read last week, should have bookmarked it.
DNA was showing a closer relationship to the other species of Jovibarba than to Sempervivum.
Also, they do not produce offsets on stolons, and have the same bloom type as the other Jovibarba species.

http://www.catalogueoflife.org...
http://ww2.bgbm.org/EuroPlusMe...
http://data.gbif.org/species/2...
http://eol.org/pages/487227/na...
http://eol.org/pages/487227/na...

Lynn, it doesn't make any sense to talk about similarities to "other Jovibarba species" because there are no other Jovibarba species. All of the Jovibarba species have been reclassified as Sempervivum species or subspecies.

The move will be tricky because it's not a straight move involving only the genus. Jovibarba hirta, for instance, is now Sempervivum globiferum subsp. hirtum. It'll also be tricky because of the custom database in the now-defunct Jovibarba genus. We don't want to lose all of the information that has been added to the Jovibarba Database, so Dave has to think of a way we can move the entries without losing the "Jovibarba" information when they're moved to the Sempervivum Database.

Anyway, this is all technical stuff that's probably of little interest to most people, so I'll send a group tree-mail to you and Chris about this.

Did you read the links that show Jovibarba and it's species is still Jovibarba, not Sempervivum?
Like this one?
http://www.catalogueoflife.org...

Lynn,

My understanding is that either you accept Jovibarba as a genus and lump hirta and arenaria and the other rollers with heuffelii OR you accept them ALL as Sempervivum, including heuffelii. The second option was how Praegar named them and we will have to go back and changed Jovibarba hirta to Sempervivum hirtum so that the Latin names agree! We need Polly back to explain the rules of Latin. She had 6 years of it!

The Jovibarba genus is well resolved cladistically because of the floral morphology and chromosome counts. Also the Jovibarba species will cross with each other (although the offspring are close to sterile) but they cross with difficulty to Sempervivum and those are VERY sterile.

This is a classic lumpers vs. splitters controversy.

Hope that helps!

Kevin

Zuzu is very good with the Latin part, but needs more information on the genetic complications between the two Genus.

Lynn, you're looking at Catalogue of Life information dated September 2012. Here's the COL information dated September 2013:

http://www.catalogueoflife.org...

Kevin, the rules of Latin names are simple. The nouns (the genera) are feminine, masculine, or neuter. The adjectives (most of the species) are also feminine, masculine, or neuter and they have to agree with the noun. That's why they change when the plant is moved to a genus of a different gender. Some species names are not adjectives, such as heuffelii, so they stay the same even after they've been moved to a genus with a name of another gender.

The perceivable differences between the two genera aren't a strong argument, Lynn. Think of Brassica rapa, for instance, which now includes broccoli raab, turnips, mustard greens, and bok choy. The genetic differences between those vegetables certainly seem obvious, but they all share the same genus and species name.