Diving beetles of the genus Rhantus in Costa Rica: Taxonomy and biogeography, with notes on South American species (Coleoptera: Dytiscidae)

Abstract

We describe Rhantus bohlei sp.n. from Costa Rican highlands. This is the fourth Rhantus species known from Costa Rica, besides of Rhantus souzannae Balke, R. gutticollis (Say) and R. calidus (F.). The latter two are wider spread, the others are endemic to Costa Rican highlands. Endemicity of the fauna is 50% (Canada: 7 species, endemicity 0). We suggest that the Costa Rican Rhantus fauna is a mixture of Laurasian and Gondwanian elements. Here, new records for the South American species Rhantus crypticus Balke and R. franzi Balke are provided.