Cranial anatomy of the giant anteater from northwestern Venezuela (Myrmecophaga tridactyla artata, Pilosa: Myrmecophagidae)

Anatomía craneana del oso hormiguero gigante del noroccidente de Venezuela (Myrmecophaga tridactyla artata, Pilosa: Myrmecophagidae)

• Juan D. Carrillo University of Fribourg, Fribourg, Switzerland.
• Luis E. Sibira Universidad del Zulia, Maracaibo, Venezuela.
• Tito R. Barros Universidad del Zulia, Maracaibo, Venezuela.

DOI: https://doi.org/10.5281/zenodo.7131289

Keywords: Xenarthra, crania, South America, tropics, morphology

Abstract

The giant anteater (Myrmecophaga tridactyla) has a wide geographical distribution in Central and South America. Three subspecies are tentatively recognized for populations in Central America and west of the northern Andes (M. tridactyla centralis Lyon, 1906), northern Colombia and northwestern Venezuela (M. tridactyla artata Osgood, 1912), and the rest of South America (M. tridactyla tridactyla Linnaeus, 1758). Myrmecophaga tridactyla artata is the less known of the three subspecies, and few specimens are deposited in zoological collections. Recent collecting efforts of specimens from north-western Venezuela allow us to better characterize this morphotype and evaluate morphological differences with the other two subspecies. We found that adult specimens of M. t. artata show smaller cranial dimensions in comparison with M. t. centralis and M. t. tridacytyla. We document a higher morphological variation than previously recognized in the cranial sutures that have been hypothesized to differentiate the subspecies. Although M. t. artata shows smaller cranial dimensions than M. t. centralis and M. t. tridactyla, additional data integrating information from the genetic variation and other morphological regions is required to further evaluate the morphological and genetic differences of the three recognized subspecies. The recently collected specimens of M. t. artata studied herein shed light on the cranial morphological variation and overlap among the three recognized subspecies of the giant anteater.

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