Affiliation:
1. Faculty of Natural Sciences, Comenius University, Zoological InstituteMlynská dolina B–2, 842 15 BratislavaSlovak Republic
Abstract
A detailed description is given of the cranial anatomy of the Lower Permian tetrapod
Discosauriscus
. This material is three–dimensionally preserved and represents one of the best know seymouriamorph tetrapods. Two species,
D. austriacus
and
D. pulcherrimus
, are distinguished in the material from the Boskovice Furrow.
D. austriacus
is abundant,
D. pulcherrimus
is rare. The two species differ in the following features: (1) the shape of the postorbital and the jugal and the nature of their junction; (2) the shape of the prefrontal and the postfrontal and the position of their contact; and (3) the morphology of the ventral surfaces fo the palatal bones and the arrangement of the denticles on them. The genus
Discosauriscus
represents larval, metamorphic and early juvenile individuals. Comparison of the cranial structures of
Discosauriscus
with those of
Seymouria baylorensis
,
Seymouria sanjuanensis
, and
Seymouria
cf.
S. sanjuanensis
(which is of similar size to the largest individuals of
Discosauriscus
) shows that (i)
Discosauriscus
and
Seymouria
are structurally similar but different genera, (ii)
Discosauriscus
is a member of the taxon Seymouriamorpha, (iii)
Discosauriscus
and
Ariekanerpeton
comprise the family Discosauriscidae and (iv)
Seymouria
is not a reptile (an amniote animal).
Ariekanerpeton
,
Utegenia
,
Urumquia
,
kotlassiids
,
leptorophids
and
Enosuchus
require revision.
Subject
General Agricultural and Biological Sciences,General Biochemistry, Genetics and Molecular Biology
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