A new genus and two new species of Southeast Asian Bidessini as well as new synonyms for Oceanian species (Coleoptera, Dytiscidae).

Michael Balke,Johannes Bergsten,Lars Hendrich,Liang-Jong Wang

doi:10.3897/zookeys.647.11231

Michael Balke, Johannes Bergsten + Show 2 more

Open Access

https://doi.org/10.3897/zookeys.647.11231

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Abstract

Rompindessus jenisi Balke, Bergsten & Hendrich, gen. n. et sp. n. is described from near Rompin village in West Malaysia. The new genus is characterized by the presence of an occipital line and basal pronotal striae, the presence of a thick anterior bead on clypeus and two-segmented parameres as well as by the absence of basal elytral striae, the absence of sutural line on elytron, the absence of basal epipleural transverse carina, and the absence of longitudinal elytral carina. Moreover, male pro- and mesotarsus appear stout, and distinctly dilated laterally; the pronotum is comparably long and parallel-sided and the colour of beetle conspicuous dark orange. Leiodytes kualalipis Balke, Wang, Bergsten & Hendrich, sp. n. is described from West Malaysia (Pahang) and South Vietnam (Cat Tien). It is well characterized by its large size, elongate body and the form of the median lobe. Limbodessus fijiensis (J. Balfour-Browne, 1944), comb. n. described from Fiji is a new synonym of Limbodessus curviplicatus (Zimmermann, 1927) described from Samoa.

Highlights

There are currently 48 genera in the Bidessini (Nilsson 2016; Miller 2016; Miller and Bergsten 2016)
Bidessini genera have to date been justified mainly on a diagnostic combination of structural features (Biström 1988; Balke et al 2002; Miller and Short 2015; Miller and Bergsten 2016) rather than apomorphies and this had to lead to recognition of genera that render other paraphyletic (Balke and Ribera 2004)
Some of these features such as presence / absence of elytral striae or occipital line have been shown to vary within clades of closely related species (Balke et al 2015) or even within one species (Balke unpublished)

Summary

Introduction

There are currently 48 genera in the Bidessini (Nilsson 2016; Miller 2016; Miller and Bergsten 2016). Of the set of structural features generally used to classify Bidessini, the following combination is present in this taxon: 1) occipital line present; 2) basal pronotal striae present; 3) basal elytral striae absent; 4) sutural line on elytron absent; 5) basal epipleural transverse carina absent; 6) clypeus with thick anterior bead (or margin); 7) longitudinal elytral carina on disc absent; and 8) parameres two-segmented. The male pro- and mesotarsus appear stout, and distinctly dilated laterally; the pronotum is comparably long and parallel-sided and the colour of beetle is conspicuously dark orange.

Results

Conclusion