Archive for March, 2011

Photon Challenge: Last Chance

March 19, 2011

Business end of Antennolaelaps

Well, this Photon Challenge has gone on long enough: last chance for demonstrating your acarological expertise. Tomorrow I will reveal all.

Kaitlin and Ray have done well to the family level of the histiostomatid, but I don’t think a leap to the genus is impossible. After all, just how many mite genera have made it into the pages of Science magazine?

Ray has an embarrassingly detailed grasp of the anthomyiids breeding in indelicate accumulations of organic matter. But no one seems to be willing to stick their neck out on the phoretic mesostigmatan deutonymphs with two dorsal shields that have a death grip at the base of the abdomen of the Eutrichota. Last hint: the family of the phoretic mesostigmatan is currently placed in the same superfamily as the Antennolaelaps featured above.

Photon Challenge: New Hints

March 5, 2011

A closer view of a mitey fly

Kaitlin and Ray have both demonstrated that even the smaller of the two mites hitching a ride on our fly can be identified to family from a not so great photo: heteromorphic deutonymphs (aka hypopi) of a member of the Histiostomatidae. They also correctly placed the larger mite to order: Mesostigmata. Not much luck on the fly, though, so I guess that means mites are easier to identify than flies? Anyone who has struggled with the generic key for this family in Nearctic Diptera might very well say yes. However, the family of the fly should be an easy guess for a dipterist.

Genus anyone?

Here’s a light microscope view (this is a Photon Challenge) of the venter of one of the histiostomatid hypopodes (yet another name for these deutonymphs) and a closeup of one of the pretarsal claws. The ventral shot is layered from three images in the wonderful CombineZP and the claw from two shots. The host association and characters visible in this image should give the discerning astigmatologist a good guess at the genus (I have checked with the North American authority on this one and he had no problem).

I’ll give one more hint on the mesostigmatans too – they also are deutonymphs.