New species of Tanaidacea from Cretaceous Kachin amber, with a brief review of the fossil record of tanaidacean crustaceans

Tanaidaceans are benthic, mostly marine, crustaceans that live burrowed in the substrate or in self-built tubes. The fossil record of Tanaidacea reaches back to the Carboniferous, 350 million years ago, but it is especially species-rich in Cretaceous amber sites from Spain and France. We report and formally describe a new species of Tanaidacea from 100-million-year-old Kachin amber, from the Hukawng Valley, Northern Myanmar, the first record of Cretaceous tanaidaceans outside Europe. The combination of character states of Tanaidaurum kachinensis gen. nov. et sp. nov. suggests that the new species is a representative of the early diversification of an unnamed group (Paratanaoidea+Tanaidoidea), an ingroup of the monophyletic group Tanaidomorpha. We briefly review the biased fossil record of Tanaidacea and present its abundance in European amber sites.