Friday, January 22, 2016

Mystery Corpse

What is it? - Mark Bower
American Dagger Moth - Sankax CC
While reviewing his fungi photographs, Mark Bower came across this puzzling creature.  On first glance I thought it resembled a caterpillar of the American Dagger Moth with a haircut.  Then I realized that its thin stems are actually jointed like legs.  That narrowed it down to an arthropod ("jointed legs").   

Narrow veined wings


Mark first discovered the narrow wings extending out at right angles.  With only one pair and without a long extended abdomen it was not likely a dragonfly.  Chris Barnhart offered the most likely guess,* "Definitely arthropod, maybe dipteran. I think I can see folded, patterned wings - so it might be Ptychoptera."

Diptera is the order of true flies, equipped with a single set of wings, its second set having evolved into stick-like halteres which serve as stabilizing structures somewhat like a gyroscope.  Ptychoptera are the Phantom Crane Flies, equipped with extended legs like a daddy-longlegs with wings.
Ptychoptera - Judy Gallagher CC






















I had already guessed* that it was transformed by a fungus but Chris added a more elegant description - an entomopathogenic fungus.  These fungi are parasitic on insects and some worm species.  They generally attach to the outside surface of the insect and in favorable conditions develop hyphae which spread into the body, injuring or killing the victim.

Entomopathogenic fungus on an earwig - aphotofungi.com

Bower the "fabulous fungi fotographer" (I love how that rolls off the tongue) got two-for-one fungi in his photograph.

*A guess by a scientist is sometimes called "a hypothesis based on careful observation but not supported by all the evidence."