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Derolathrus cavernicolus Peck (Jacobsoniidae) - Derolathrus cavernicolus

Derolathrus cavernicolus Peck (Jacobsoniidae) - Derolathrus cavernicolus
Citrus County, Florida, USA
In old bat guano in cave.

Moved per Dr Thomas's info here from Derolathrus.

Two more down! Great pictures
Two more down! Great pictures!

I can't believe how many weird families you have in your collection. 4 more families left!

but the collection isn't actually mine, although I do feel rather possessive about it. The specimens are from the Florida State Collection of Arthropods in Gainesville.

makes me wonder... guys like that one after a long journey all over Coleoptera could end up --of all places-- among elateroids... sssssso counter-intuitive :-]

Jacobsoniidae placement
And now several recent morphological and molecular studies put them into or as sister of Staphylinoidea! They'll be treated there in the forthcoming (in a couple years) Beetles of Canada and the US, successor to the now 20-year-old American Beetles.