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Issue: Vol. 5862 No. 1: 4 Aug. 2026
Type: Article
Published: 2026-08-04
DOI: 10.11646/zootaxa.5862.1.4
Page range: 105-126
Abstract views: 371
PDF downloaded: 34

New data on the genus Laccosternus Brancucci, 1983, with description of the male of L. grouvellei (Régimbart, 1895) and a revised phylogeny of the tribe Laccophilini (Coleoptera: Dytiscidae: Laccophilinae)

Department of Sustainable Crop Production DI.PRO.VE.S.; Università Cattolica del Sacro Cuore; via Emilia Parmense 84; I-29122; Piacenza; Italy
Thailand National History Museum; National Science Museum; Pathum Thani; 12120 Thailand; Coleopterological Society of Japan; National Museum of Nature and Science; Tsukuba; 3050005 Japan
Department of Sustainable Crop Production DI.PRO.VE.S.; Università Cattolica del Sacro Cuore; via Emilia Parmense 84; I-29122; Piacenza; Italy
Coleoptera Diving beetles Laccophilini new records taxonomy phylogeny new characters Thailand

Abstract

The genus Laccosternus Brancucci, 1983 (Dytiscidae, Laccophilinae) is recorded from Thailand for the first time. This newly collected material allows a better knowledge of this very poorly known taxon. Both of its species, Laccosternus grouvellei (Régimbart, 1895) and L. krausi Brancucci & Vongsana, 2013, were found in different parts of the country, although not in sympatry, and are revised based on these Thai specimens. The male of Laccosternus grouvellei is described for the first time and a new diagnosis of Laccosternus is given, including newly introduced characters. Habitus, male genitalia and details of other characters are illustrated for both species. A distribution map and ecological notes are also presented. The phylogenetic position of Laccosternus within the tribe Laccophilini is studied based on a cladistic analysis of 21 adult morphological characters across all 14 genera and eight crucial species-groups of Laccophilinae, including Agabetes Crotch, 1873 as outgroup. The results recover three principal clades within Laccophilini and strongly support a sister-group relationship between Laccosternus and the New World genus Laccomimus Toledo & Michat, 2015. The positions of Australphilus Watts, 1978 and Laccoporus J. Balfour-Browne, 1938 remain weakly resolved. The last available key to the genera of Laccophilini is modified to fit the new concept of Laccosternus.

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How to Cite

Toledo, M.E., Okada, R. & Negri, I. (2026) New data on the genus Laccosternus Brancucci, 1983, with description of the male of L. grouvellei (Régimbart, 1895) and a revised phylogeny of the tribe Laccophilini (Coleoptera: Dytiscidae: Laccophilinae). Zootaxa, 5862 (1), 105–126. https://doi.org/10.11646/zootaxa.5862.1.4