Jaw anatomy of Potamogale velox (Tenrecidae, Afrotheria) with a focus on cranial arteries and the coronoid canal in mammals.
Afrotheria is a strongly supported clade within placental mammals, but morphological synapomorphies for the entire group have only recently come to light. Soft tissue characters represent an underutilized source of data for phylogenetic analysis, but nonetheless provide features shared by some or all members of Afrotheria. Here, we investigate the developmental anatomy of Potamogale velox (Tenrecidae) with histological and computerized tomographic data at different ontogenetic ages, combined with osteological data from other mammals, to investigate patterns of cranial arterial supply and the distribution of the coronoid canal. Potamogale is atypical among placental mammals in exhibiting a small superior stapedial artery, a primary supply of the posterior auricular by the posterior stapedial artery, and the development of vascular plexuses (possibly with relevance for heat exchange) in the posterior and dorsal regions of its neck. In addition, the posterior aspect of Meckel's cartilage increases its medial deflection in larger embryonic specimens as the mandibular condyle extends mediolaterally during embryogenesis. We also map the distribution of the coronoid canal across mammals, and discuss potential confusion of this feature with alveoli of the posterior teeth. The widespread distribution of the coronoid canal among living and fossil proboscideans, sirenians, and hyracoids supports previous interpretations that a patent coronoid canal is a synapomorphy of paenungulates, but not afrotherians as a whole.
Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom; Department of Zoology, University of Cambridge, Cambridge, United Kingdom.
Robert J
RJ
Brocklehurst
Department of Zoology, University of Cambridge, Cambridge, United Kingdom; Research Department of Cell & Developmental Biology, University College London, United Kingdom.
Nick
N
Crumpton
Department of Zoology, University of Cambridge , Cambridge , United Kingdom.
Evie
E
Button
Department of Zoology, University of Cambridge , Cambridge , United Kingdom.
Robert J
RJ
Asher
Afrotheria; Arteries; Coronoid canal; Mandible; Ontogeny; Paenungulata; Soft tissues