Thalassocnini

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 : 1530

Thalassocnini plus Megatheriini

PP = 99, age = 12.03 Mya (10.56–13.75).

This clade was consistently recovered in all analyses performed in this study although, as stated above, a monophyletic Thalassocnini is absent from par_IW5.

The clade was supported by nine synapomorphies (seven for both methods and two exclusively for BI): premolariform portion of palate much shorter than the length of molariform toothrow (BI); lateral and medial palatal processes of maxilla of equivalent length; ectotympanic fused dorsally; hypoglossal foramen recessed dorsally, lies at same level as jugular foramen (BI); hemispherical glenoid fossa; three shallow grooves for tendons of m.flexor hallucis longus, m.flexor digitorum longus and m. tibialis caudalis; odontoid process of astragalus well defined along entire proximodistal length of tibial surface; discoid and odontoid facets of astragalus roughly at right angles to one another in distal view; and proximodistal length of astragalus greater than or equal to anteroposterior length.