Kingdom Plantae
Phylum Magnoliophyta
Class Magnoliopsida (Dicotyledons)
Sub-Class Rosidae
Order Rosales
Family Crassulaceae
Genus Jovibarba
Species Approximately 5
Jovibarba has variously been considered:
Taxonomy is quite an evolving science, and it is best left to botanists to debate the relationship of
jovibarba to other similar
genera. At this point (as of 2001),
Jovibarba is considered a unique genus, after having been removed as a subgenus (or
section) of
sempervivum. This is a subject of intense
debate.
Visible traits of
jovibarba which differ from traits of
sempervivum involve the shape and colour of the flowers (
jovibarba having bell shaped, pale yellow flowers), and the shape of pollen grains (
jovibarbas being barrel shaped). The discovery of difference in pollen is one of the most compelling reasons for
jovibarba being classed as it's own
genus.
I will attempt to provide more details -- I am trying to get my hands on a paper entitled
Selected problems of the taxonomic differentiation of the genera Sempervivum and Jovibarba in Europe which is a PhD thesis by Dominik Roman Letz, in the Slovak Republic.
The word
jovibarba itself means "Jove's Beard",
Jove being another name for
Jupiter.
references: a wonderful site called sempervivophilia, found at http://gdumont.multimania.com/home_js.htm