Megatheriidae

Casali, Daniel M, Boscaini, Alberto, Gaudin, Timothy J & Perini, Fernando A, 2022, Reassessing the phylogeny and divergence times of sloths (Mammalia: Pilosa: Folivora), exploring alternative morphological partitioning and dating models, Zoological Journal of the Linnean Society 196 (4), pp. 1505-1551 : 1528

Megatheriidae

PP = 100, age = 20.43 Mya (18.28–22.99).

This clade is composed of the genus Analcimorphus and the clades Prepotheriinae , Nothrotheriinae and Megatheriinae . Megatheriidae was recovered in all MP analyses and all BI analyses with H models, and was absent in all analyses with UN and A models, given the nested position of Mylodontoidea in this clade. Analcimorphus was consistently recovered as a stem member of this clade.

Megatheriidae was supported by 12 synapomorphies (eight for both methods and four exclusively for BI): presence of fossa anterior to Cf1 (BI); snout length greater than its width, but no longer than two times the width; uniform nasal width in its posterior half, with lateral margins parallel (BI); premolariform portion of palate roughly equal or longer than molariform toothrow; absence of a crest at median suture of palatine (BI); absence of a marked postorbital constriction; well-developed ventral nuchal crest; carotid foramen fully covered in ventral view; entotympanic dorsal edge with a strong concave curvature in lateral view, and a dorsal projection at anterior end; entotympanic forming almost the entire floor of the tympanic cavity medial wall; nuchal and exoccipital crests parallel (BI); and lateral expansion of metatarsal V proximolaterally oriented.