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Ichibengops, new eutherocephalian synapsid from Upper Permian of Zambia

Ben Creisler

A new online paper:

Ichibengops munyamadziensis

Adam K. Huttenlocker, Christian A. Sidor & Kenneth D. Angielczyk (2015)
A new eutherocephalian (Therapsida, Therocephalia) from the upper
Permian Madumabisa Mudstone Formation (Luangwa Basin) of Zambia.
Journal of Vertebrate Paleontology (advance online publication)

A new therocephalian therapsid, Ichibengops munyamadziensis, gen. et
sp. nov., is described on the basis of two partial skulls from the
upper Permian (Wuchiapingian) upper Madumabisa Mudstone Formation of
the Luangwa Basin, Zambia. The specimens offer insights into the
diversity of therocephalians in a poorly sampled region, preserving
unique maxillary structures, dental morphology that is intermediate
between basal therocephalians and eutherocephalians, and a
maxillovomerine bridge forming an incipient secondary palate. A
phylogenetic analysis of 135 craniodental and postcranial characters
from 56 therapsid taxa (including 49 therocephalians) recovered I.
munyamadziensis as the sister taxon of the Russian Chthonosaurus, with
both taxa resolving near the hofmeyriid + whaitsiid + baurioid clade
(either as the sister group to this clade or nested near whaitsiids).
Ichibengops shares with Chthonosaurus several features, including a
ventral maxillary flange in which the upper postcanines are situated
(also in Lycosuchus), anteroposteriorly short suborbital vacuities
with strongly scalloped anterior borders, a furrowed or ridged surface
texture on the palatal surface of the palatine, and a possible
maxillovomerine bridge (although this latter structure is incompletely
preserved in Chthonosaurus). The new taxon, along with its proposed
relationship to Chthonosaurus, adds to a list of sister-group pairs of
Wuchiapingian tetrapods in southern Gondwana and Laurasia, indicating
that effective, though largely unknown, dispersal routes persisted in
Pangea at least through early late Permian times.