Малаколог

Вот в свежей статье Кэмерон пишет, что скорее более 50 тысяч видов одних наземных:
http://www.bioone.org/doi/full/10.4003/006.031.0108

With an accumulated load of perhaps 300,000 names and a synonymy ratio that is matched
probably only in butterflies, molluscs are certainly the marine group where
the number of names and number of species are most at odds with each other.
We do not even know whether the number of valid named Recent species of
molluscs is on the order of 45,000 or 130,000 (see table 2.2), an uncertainty
that is admittedly pervasive among Recent and fossil biota but is seen as “particularly
problematic” for molluscs (Hammond 1995).
THE MAGNITUDE OF MARINE BIODIVERSITY by Philippe Bouchet (The Exploration of Marine Biodiversity Scientific and Technological Challenges) Carlos M. Duarte (ed.) 2006