The braincase of Leptopleuron lacertinum Owen, a leptopleuronine procolophonid from the Late Triassic (lower Norian) of Scotland, is described for the first time. Morphologically, the braincase of Leptopleuron is similar to that of the Early Triassic genus Procolophon, and to a number of other procolophonids currently included in the subfamily Procolophoninae Romer, 1956. Several features of the braincase of Leptopleuron are derived within the Procolophonidae, but others are unique to this genus. Apomorphies include a strongly tripartite occipital condyle, a metotic foramen that is not walled by bone anteriorly, an ‘ascending process’ of the basisphenoid that forms a robust flat-ended expansion, and bears ventrally a thin laterally directed lamella, a ‘processus infrastapedialis columellae’ of the stapes that is aligned with the long axis of the footplate, loss of the foramen for nerve IX on the ventral ramus of the opisthotic, and a greatly expanded, vertical basisphenoid rostrum. These features may be autapomorphic for Leptopleuron, or represent synapomorphies of the Leptopleuroninae Ivakhnenko, 1979.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.