Acta Palaeontologica Polonica

Veliger morphs in Pristiograptus, a robust graptoloid from the Ludlow series (Silurian) of Morocco

Barrie Rickards

Acta Palaeontologica Polonica 46 (3), 2001: 447-451

The velum of veliger morphs is a rare, impersistent, delicate structure developed on the thecal apertures of some graptolites, and which may become stabilised in evolutionary descendants, thereby producing a new morphotype. This paper describes their discovery for the first time in the genus Pristiograptus.

Barrie Rickards [ ], Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.