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Menadon besairiei, cynodont from Madagascar Triassic now found in Brazil

Ben Creisler

A new paper:

Tomaz Panceri Melo, Fernando Abdala & Marina Bento Soares (2015)
The Malagasy Cynodont Menadon besairiei (Cynodontia; Traversodontidae)
in the Middle–Upper Triassic of Brazil.
Journal of Vertebrate Paleontology (advance online publication)
DOI: 10.1080/02724634.2014.1002562

The traversodontid cynodont Menadon besairiei, previously known from
the ‘Isalo II’ group of Madagascar, is reported for the first time
from the Triassic of southern Brazil. New material referable to M.
besairiei was collected in the Schoenstatt outcrop (Santa Cruz do Sul
municipality), which belongs to the Santacruzodon Assemblage Zone
(Carnian) in the Santa Maria Supersequence. Their attribution to the
Malagasy taxon is based on the presence of a deep snout; four upper
incisors, with procumbent first and second incisors, and three lower,
procumbent incisors; five upper postcanines, the first one ‘peg-like’;
six lower postcanines, the two most anterior and the most posterior
being reduced; the quadrangular form of the postcanines; a pterygoid
reaching the jugal and excluding the maxilla from the suborbital
fenestra; a mandible with a tall coronoid process covering the last
lower postcanine laterally; and a posteriorly projected angular
process. A cladistic analysis of traversodontid cynodonts was
performed based on a matrix composed of 30 taxa and 78 characters. In
the resulting trees, M. besairiei nested within the clade
Gomphodontosuchinae, the only traversodontid subclade reasonably well
supported. Thus, the presence of M. besairiei is established in the
Santa Cruz do Sul fauna, constituting the first record for South
America and confirming the previously proposed biostratigraphic
correlation between the ‘Isalo II’ and the Santacruzodon Assemblage