Re: [beemonitoring] Ceratina dupla vs. Ceratina calcarata females
- FYI, I wasn't intending to reply to this whole list but only to Sam.
> Are you sure this applies to all populations (e.g., dupla floridana)?
> I wasn't confident in the characters on the poster by the Canadians. The
> punctures seemed to vary a lot.
> On another subject, I find it easy to distinguish Megachile brevis vs.
> mendica and question their being indistinguishable. I find Mitchell's
> characters of the tergal apex useful and rarely have problems. I can even
> tell texana vs. mendica most of the time, although some specimens are
> genuinely puzzling.
>> Given the prevalance of these two species, I thought it worth sending
>> a quick note about discriminating the females. Expanding on Sandra
>> work on discriminating Ceratina dupla from C. calcarata I recently found
>> another character that will help separate the two, this requires more
>> experience but is useful for discriminating inbetween specimens.
>> I have added the following to the Ceratina guide:
>> With experience and a good series of both species the propodeal triangle
>> can be used to discriminate among ambiguous specimens. In dupla the
>> striations extend usually rather uniformly about two-thirds of the way
>> edge across the entire width, these striations are usually dense enough
>> that it is difficult to discriminate individual members. In calcarata
>> basal striations extend about two-thirds or more of the way in the
>> but this proportion decreases to the sides, thus leaving a non-uniform,
>> unstriated portion of the rim of the triangle; the striations can be
>> widely spaced and usually are clearly separable from their neighbors,
>> additionally the entire triangle tends to be longer in comparison to
> John S. Ascher, Ph.D.
> Bee Database Project Manager
> Division of Invertebrate Zoology
> American Museum of Natural History
> Central Park West @ 79th St.
> New York, NY 10024-5192
> work phone: 212-496-3447
> mobile phone: 917-407-0378
> Yahoo! Groups Links
John S. Ascher, Ph.D.
Bee Database Project Manager
Division of Invertebrate Zoology
American Museum of Natural History
Central Park West @ 79th St.
New York, NY 10024-5192
work phone: 212-496-3447
mobile phone: 917-407-0378