Prosopeus

Murray, 1864 (=Nesopeplus Sharp1908) (=Nesopetinus Sharp 1908) Ewing, 2004

 

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The genus Prosopeus was described by Murray in 1864 based on a single specimen that he believed originated from South Africa. Examination of the type specimen shows it to be a species of Hawaiian origin.

Most species are very small, 2-4mm, though a few do approach 6mm. They are usually convex and their pronotal and elytral margins are narrowly explanate. They exploit a wide variety of host plants. Many species are limited to a single genus of host, while others can be found on nearly every plant in the forest.

All but one of the species included in this genus are from the genera Nesopeplus and Nesopetinus. Nesopeplus and Nesopetinus were defined based on the size and shape of the prosternal process. This character is very plastic and both genera are paraphyletic with respect to the other.

The species in this genus are the only endemic sap beetles to be commonly seen in flight during the day. A higher percentage of Prosopeus species utilize fresh flowers than any other genus of Hawaiian sap beetles. Flowers are an ephemeral food source and their exploitation is facilitated by flight. Species of Prosopeus vector Hawaiian endemic yeast species between flowers.