Gyrinus oblongus Boisduval, 1835

Fery, Hans & Hájek, Jiří, 2016, Nomenclatural notes on some Palaearctic Gyrinidae (Coleoptera), Acta Entomologica Musei Nationalis Pragae 56 (2), pp. 645-663 : 651

Gyrinus oblongus Boisduval, 1835

Recently, we found a work of Ludwig Heinrich Freiherrn von Block ( BLOCK 1799) in which also eight hydradephagan species are dealt with. This work is mainly a list of species which have been found at that time in the ‘Plauischer Grund’, a landscape in the south-west of Dresden ( Germany). In this list are included descriptions of a few new taxa, the single hydradephagan of them is Gyrinus oblongus Block, 1799 on page 100 (see also BOUSQUET 2016: 81). The only other Gyrinidae species listed is Gyrinus natator . The description is rather short and scarce, and can be applied to several Gyrinus species known to occur near Dresden. We have no information on the whereabouts of Block’s collection, and thus it seems to be impossible to clear the identity of his species. As far as we know, Gyrinus oblongus Block was never mentioned as the valid name of any species since its description, in particular not after 1899. Accordingly, Gyrinus oblongus Boisduval, 1835: 52 (currently in Macrogyrus ) described from ‘Nouvelle-Hollande’ [= Australia] is a junior primary homonym of Gyrinus oblongus Block, 1799 , and thus Boisduval’s name should be permanently invalid.

However, mainly due to the fact, that Macrogyrus oblongus was one of the first Coleoptera species with completely sequenced mitochondrial genome, there exist at least 30 works published during last 50 years and by more than 10 authors (see Appendix) in which M. oblongus is mentioned as a valid name of the species. According to Article 23.9.2 of the ICZN (1999), we fix here the precedence of the younger name Gyrinus oblongus Boisduval, 1835 over the older name Gyrinus oblongus Block, 1799 , and thus Boisduval’s name is qualified by the term nomen protectum and Block’s invalid, but older, name by the term nomen oblitum.