|Inventorying the molluscan diversity of the world: what is our rate of progress?|
Bouchet, P. (1997). Inventorying the molluscan diversity of the world: what is our rate of progress? Veliger 40(1): 1-11
In: The Veliger. California Malacozoological Society: Berkeley, CA,. ISSN 0042-3211, more
Ecological distribution; Habitat; New taxa; Species diversity; Taxonomy; Mollusca [WoRMS]; Marine
Levels and trends in the naming of new mollusk species over the last 30 years are reviewed through analysis of a sample of 12,561 names extracted from nine volumes of Zoological Record. On average, 1395 new species-group mollusks are being named each year, of which 69% are fossils (average yearly increment: 366 Recent gastropods, 292 fossil gastropods, 42 Recent bivalves, 316 fossil bivalves, 320 fossil cephalopods, and 59 other Recent and fossil mollusks). Using a smaller sample of 1996 names, the synonymy ratio of Recent taxa is calculated to be 1.6, i.e., about 265 new valid species are named each year. Over the past 25 years, the number of new marine species described each year has increased by 68%, whereas the number of new non-marine species has decreased by 15%. The most significant decrease concerns tropical continental faunas. Possibly as many as half of the new descriptions of Recent species are by people not funded for this purpose, with amateurs authors of 28% of the descriptions. The United States has the most active scientific professional and non-professional community, being responsible for over 20% of new Recent species. Nearly half of the new species worldwide are described in malacological journals. With a collecting effort of marine mollusks increased by several orders of magnitude in the last few decades, there is no sign of leveling off in the inventory of molluscan diversity. For the foreseeable future, micromollusks, the deep-sea, and the marine and non-marine tropics will remain effectively inexhaustible reservoirs of undescribed species. From a conservation perspective, the loss of knowledge of and attention to tropical land and freshwater faunas is dramatic, considering loss of habitat and extinction.