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 – Dolichostyrax moultoni Aurivillius, 1911 and Dolichostyrax 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., Microdolichostyrax 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 Dolichostyrax 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.

State of knowledge of viviparity in Staphylinidae and the evolutionary significance of this phenomenon in Corotoca Schiødte, 1853

“…In the description of the only known case of viviparity in Cerambycidae, Gabriš et al (2016) take the absence of spermatheca, along with other features, as a clear indication of viviparity condition in the species. The authors explained that this phenomenon -loss of spermatheca -also happens in viviparous chrysomelids.…”

“…Related to Coleoptera, he compiled the cases of viviparity for Micromalthidae, Staphylinidae and Chrysomelidae. For the next 50 years, the new registers for this phenomenon are related to three tribes of Tenebrionidae (Oncotini, Platynotini and Ulomini) (Tschinkel, 1978;Iwan, 2000;Dutrillaux et al, 2010), one genus of Carabidae (Pseudomorpha Kirby (Liebherr & Kavanaugh, 1985)), and one genus of Cerambycidae (Borneostyrax Gabriš (Gabriš et al, 2016)). Glaçon-Deleurance (1963) stated that beetles from tribe Leptodirini (Leiodidae), extremely modified for cavernicolous habitus, apparently deposit a single egg already with a fully developed larva.…”

Taxonomic revision of the endemic Bornean genera Anexodus Pascoe and Pantilema Aurivillius (Coleoptera, Cerambycidae, Lamiinae)

“…A slash (/) is used to separate lines on the same label and a double slash (//) is used to separate different labels on the pin. The morphological terminology is used as in Gabriš et al (2016), following those in Ślipiński and Escalona (2013) and Švácha and Lawrence (2014).…”

“…This is also currently the case with Morimopsini, an assemblage of about 50 lamiine genera known mainly from the Afrotropical and Oriental Regions (Sudre and Teocchi 2002, Vitali and Menufandu 2010, Weigel 2015, Gouverneur 2016). Several taxa now assigned to Morimopsini occur also in Borneo (Breuning 1950, Gabriš et al 2016). Pascoe (1886) described the genus Anexodus Pascoe for A. aquilus Pascoe, 1886 from Sabah.…”

“…Since then, nobody has published on the morimopsine fauna of Borneo until Sudre (1997) described Anexodus sarawakensis Sudre, 1997 based on three specimens from Sarawak. Recently, Gabriš et al (2016) revised the Bornean species of Dolichostyrax and described four species from Sabah for which they established three new genera, i.e. Borneostyrax , Eurystyrax , and Microdolichostyrax .…”