CLEMatis...

[Jan Ivarsson TransEdit]

http://www.saltspring.com/capewest/pron.htm gives simple rules for the English pronunciation of biological Latin, including taxonomic names of plants and animals. It recommends CLEMmatis. One might hope that people more often would look up pronunciation in some kind of source, dictionary or other.
But it is probably a hopeless task to get specialists in any field to doubt their way of pronouncing words of foreign origin. I have heard computer people heatedly sustain that the correct pronunciation is VerbaTIM and PaGIna (the brand names for their own corporations).
Jan Ivarsson
jan.ivarsson at transedit.st