Review of Dolichostyrax Aurivillius (Cerambycidae, Lamiinae) in Borneo, with descriptions of three new genera and the first case of (ovo)viviparity in the long-horned beetles

Abstract

We reviewed the species of genus Dolichostyrax Aurivillius (Cerambycidae: Morimopsini) from Borneo, which included the redescriptions of two species – D. moultoni Aurivillius, 1911 and D. longipes Aurivillius, 1913, with the first female description for the latter. After the examination of the additional material previously identified as Dolichostyrax, we described three new genera – Borneostyrax gen. n., Microdolichostyrax gen. n., and Eurystyrax gen. n. Borneostyrax cristatus sp. n. was described based on the male and female specimens, whilst Microdolichostyrax hefferni sp. n., M. minutus sp. n. and Eurystyrax nemethi sp. n. are known only from females. All studied species are distributed in the mountain regions of Sabah, with the exception of D. moultoni from Sarawak. An identification key to the genera of Bornean Morimopsini and species of Dolichostyrax, Borneostyrax gen. n., Microdolichostyrax gen. n. and Eurystyrax gen. n. is provided and their distributions and intraspecific morphological variability are discussed. The short and wide ovipositor, loss of spermatheca, and presence of large larvae without apparent eggbursters inside the female abdomens indicate the presence of (ovo)viviparity in Borneostyrax gen. n. This is the first case of this rare phenomenon within Cerambycidae.