The Crassulaceae Family was named and described by Jean Henri Jaume Saint-Hilaire in Exposition des Familles Naturelles in 1805.
Plants of the World Online lists 29 accepted genera in this family commonly known as the stonecrop or orpine family. They are still uploading data so this figure could change. Ummm… It will periodically change anyway
The Wikipedia says there are 34 or 35 genera which include approximately 1,400 species.
The 2013 version of The Plant List (now unmaintained) includes(ed) 50 genera in this family with a number of unresolved names. In the 50 genera, there are a total of 1,671 accepted species and infraspecific names, 3,164 synonyms, and 1,794 unresolved names. GEEZ!
The International Crassulaceae Network lists 51 genera but I am not sure when the site was last updated. I became acquainted with Margrit Bischofberger in 2013 and she helped me resolve several misnamed plants I had. She is an older lady from Switzerland and the last few emails to her weren’t answered.
There are several intergenic hybrids in the Crassulaceae Family such as:
xCremneria (Cremnophila x Echeveria),
xCremnopetalum (Graptopetalum x Cremnophila),
xCremnosedum (Cremnophila x Sedum),
xGraptophytum (Graptopetalum x Pachyphytum),
xGraptosedum (Graptopetalum x Sedum),
xGraptoveria (Graptopetalum x Echeveria),
xLenopetalum (Lenophyllum x Graptopetalum),
xPachysedum (Sedum x Pachyphytum),
xPachyveria (Pachyphytum x Echeveria),
xSedeveria (Sedum x Echeveria),
xTacipetalum (Graptopetalum x Tacitus),
xTacisedum (Tacitus x Sedum (some Graptopetalum x xGraptosedum/Tacitus x xTacisedum)), AND
xTaciveria (Tacitus x Echeveria)
Of course, with the testing, some of the above names may change and may not even be intergenetic hybrids after all. Time will tell… Maybe even as I write this they have already changed. Maybe I should check and make sure…
For more information about this family of plants, please click on the links below. The links take you directly to the information about the family.