[Taxacom] Total number of name-bearing types

Kenneth Kinman kennethkinman at webtv.net
Wed Jan 14 20:03:04 CST 2009

Dear All,
      This is a very interesting question, and I was happy to see that
Chris Thompson could provide some minimal numbers for Diptera:  "at
least" 185,000 type specimens for about 154,000 species of flies.
However, I was disappointed that there was no further discussion for
other taxa.   Of course this is somewhat understandable given the
uncertainty as to the total numbers of accepted species of living
organisms that have been described and generally accepted.
      Anyway, Chris came up with approximately a ratio of 1.4 of type
specimens/accepted described species.  I suspect beetles are a little
lower than 1.4, and that ants are probably higher than 1.4 (since
syntypes series of ants can often include not only males and females,
but workers as well).  Although many mammalogists are not well tuned
into the huge number of subspecies and synonyms (which each have their
own types), my own studies indicate that the ratio of type specimens to
recognized species is probably relatively high (easily 5.0, if not
more), and I suspect the same is true of birds.  I just wonder if fish
(higher in numbers of species), also have anything like this ratio.          
      In any case, I would estimate the number of described "accepted"
species of living organisms to be at least 1,700,000.  If we assume a
minimum ratio of 1.5 for organisms as whole, we are talking about a
minimum of 
2,350,000 type specimens.  I suspect that it is closer to 3,000,000 if
not more.  I just wish I knew more about the prevalence of angiosperm
syntype series (and their numbers) to estimate the ratio for that rather
speciose group.  Is it much greater than 1.4 that was estmated for the
minimum of Dipteran type specimens?  An estimated ratio for molluscs
(another speciose group) would also be helpful. 
                          Ken Kinman

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