A Maastrichtian (Late Cretaceous) record of the brachylepadid cirripede genus Pycnolepas from northeast Belgium

摘要

A new species of the genus Pycnolepas WITHERS, 1914 (Cirripedia, Brachylepadomorpha), Pycnolepas industriosa sp. nov., is described. Based on a single rostrum from Interval 4 of the Vijlen Member (Gulpen Formation; lower upper Maastrichtian in belemnitellid coleoid terms) at Altembroeck (Voer, northeast Belgium), it would appear to be most closely related to the late Paleocene P. landenica Withers, 1953, also from Belgium. Unlike the only other extinct brachylepadid genus, Brachylepas WOODWARD, 1901, of which at least nine species of late Turonian to latest Maastrichtian age are now known from North America, Europe and Kazakhstan, Pycnolepas is extremely rare in Campanian and Maastrichtian strata across Europe and Asia. The only previous records are those of P. ignabergensis CARLSSON, 1953 (uppermost lower Campanian; southern Sweden) and P.? orientalis KOLOSVARY, 1966 (unspecified Upper Cretaceous; Azerbaijan). In view of the fact that both the original description and illustrations of the latter species are insufficient, and that the current whereabouts of the type material is unknown, it is best considered a nomen dubium. Species of Pycnolepas currently considered valid are of early(?) Aptian, early Albian to late(?) Cenomanian, early Campanian, late Maastrichtian, early and late Paleocene and early Miocene age, with records from Antarctica, Europe (including Ukraine), Kazakhstan and Far East Russia.