A species-group key and notes on phylogeny and character evolution in New Guinean Exocelina Broun, 1886 diving beetles (Coleoptera, Dytiscidae, Copelatinae)

Abstract

Detailed information about the known species groups of Exocelina Broun, 1886 from New Guinea is presented, including species numbers, distribution, and references of species-group diagnoses, keys to the species, and species descriptions. An identification key to all species groups is provided. Phylogeny and morphological character evolution are discussed.

Austrelatus gen. nov., a new genus of Australasian diving beetles (Coleoptera, Dytiscidae, Copelatinae), with the discovery of 31 new species from New Guinea

“… Copelatinae , the second largest subfamily of Dytiscidae , has been so far represented in Australasia by two genera, Copelatus Erichson, 1832 and Exocelina Broun, 1886, and the majority of species occurs in New Guinea. One hundred and fifty-two species of New Guinean Exocelina were treated in our previous publications, the results being summarised by Shaverdo and Balke (2022) . Copelatus , the most speciose diving beetle group, is known in New Guinea only from 17 described species ( Régimbart 1899 ; Zimmermann 1919 ; Balfour-Browne 1939 , 1945 ; Guignot 1942 , 1956 ; Guéorguiev 1968 , 1978 ; Guéorguiev and Rocchi 1993 ; Shaverdo et al 2008 ; Megna et al 2017 ; Hendrich et al 2019 ; Nilsson and Hájek 2023 ).…”