Osteoderm morphology and taxonomy of Pampatheriidae (Cingulata, Xenarthra) from the Quaternary of the Neotropical region

Author(s)

Ferreira, Thais Matos Pereira ; Casali, Daniel de Melo ; Das Neves, Simone Baes ; Ribeiro, Ana Maria

• Document type: Journal article
• Source: HISTORICAL BIOLOGY; v. N/A, p. 19-pg., 2025-01-08.

Abstract

This study analyses Neotropical Quaternary pampatheriids' osteoderm morphology and reviews their taxonomic history since the first publications accounting for dermal plates. The main objectives are to illustrate and describe for the first time the first osteoderms attributed to Pampatherium humboldtii and the lectotype of Holmesina major, both from Lund's publications; as much as the neotype of P. typum from Ameghino's first records, and the hypodigms designated in this paper; and also, to re-evaluate the taxonomy and redescribe in greater detail the osteoderms from the hypodigm of P. mexicanum, H. paulacoutoi, and H. occidentalis. The taxa Tonnicinctus mirus, H. cryptae, H. floridana, H. septentrionalis, Plaina intermedia, Pl. subintermedia, and Pl. brocherense are used solely for comparative analysis. The results allowed the definition of morphological patterns. All taxa are considered to be valid, except for the synonymy herein proposed between H. major and H. paulacoutoi, based on morphological, geographical, and historical data, with H. major taking precedence. Furthermore, the morphological pattern of the osteoderms of H. cryptae is considered equivalent to that of the genus Pampatherium. It is suggested that future studies should be carried out using cranial and other skeletal elements to further evaluate the taxonomic status of H. cryptae. (AU)

• FAPESP's process: 22/00044-7 - Phylogeny, divergence times and historical biogeography of Xenarthra (Mammalia, Eutheria): combining morphological and molecular data
• Grantee: Daniel de Melo Casali
• Support Opportunities: Scholarships in Brazil - Post-Doctoral