Species of Hollinella (Palaeocopida: Ostracoda: Crustacea) as stratigraphical indices of the Late Permian-Early Triassic post-extinction interval

Members of the ostracod order Palaeocopida, except three very rare genera (Puncia, Manawa and Promanawa), disappeared from the stratigraphical record close to the Permian-Triassic boundary (PTB) event. Species of the genus Hollinella are often present just after the end-Palaeozoic mass extinction event, in latest Permian and earliest Triassic beds. They are among the last representatives of Palaeocopida, the typical Palaeozoic straight dorsal border ostracods. The Early Triassic species have been assigned by most authors to Hollinella tingi (Patte, 1935), but this assignment is incorrect. This species is present in the latest Permian and the earliest Triassic, and therefore is considered a biostratigraphical index fossil of the post-mass extinction interval. A revision of Hollinella species from this interval is presented here. Three Hollinella species occur in the earliest Triassic: H. panxiensis Wang, 1978; H. magninoda Wang, 1978; and Hollinella (Hollinella) lungcamensis Crasquin sp. nov. The new species of the post-PTB event is present in strata exposed in the northern part of Vietnam. All three species of Hollinella cross the PTB and H. (H.) lungcamensis is characteristic of the post-extinction period (latest Changhsingian-earliest Induan).http://zoobank.org/urn:lsid:zoobank.org:pub:C8BA4418-B7FE-4B28-ADA0-28BE317687A4