Ripiphorus Species (possibly R. rex).
https://www.inaturalist.org/observations/25228961
by @merav
San Diego County only has two observations of these unique looking beetles, both in the month of May at Anza Borrego State Park.
These beetles have very short elytra that leave their wings exposed. They are often active on Sweetbush, though our observation is a very popular bachelor hangout (possibly near a patch of sweetbush?). Can anyone identify the plant?
Ripiphorus species have a fascinating life cycle. The female will lay eggs in flower buds and the larva will emerge at the same time the bloom matures. The larva will then hitch a ride on a bee and end in a bee nest cell, where it will parasitize a bee larva. Adults only live one to two days so the race is on to mate and lay eggs again!
The preferred bee species hosts are unknown.
Our two observations were in the month of May but Desert Insects & Kin (Lynn & Gene Monroe) describe an encounter in mid-March so both the Border Bioblitz 2021 and the City Nature Challenge should offer opportunity for some sightings if you find yourself in the desert region.
Who's up for the challenge?? I know these are now on my "bugket list" :)
Note: There is some controversy about the spelling of this genus, sometimes with an 'h' after the first 'R'. I stopped fighting the autocorrect which did not want to accept the more recent spelling iNat is using.
