::Removed refs to Ponder & Lindberg (2008) as no-one's come forward with the required info. Added 1 source for species counts and others for descriptions and habitats in "Classification" section. Species count goes down from Ponder & Lindberg's 250,000 to "only" 93,000. The range I found while searching was generally 70,000 to 100,000. The source I used specifically says "described species", i.e. recognized in scientific publications, so at least I know what the counts mean. I can only assumed the figures quoted from Ponder & Lindberg (2008) include a guesstimate of undiscovered species, which would be rather  speculative & subjective. 
 ::Also removed class Tentaculita† from taxobox as not mentioned in any of the refs I've seen.