Dental microwear in the orthodentine of the Xenarthra (Mammalia) and its use in reconstructing the palaeodiet of extinct taxa: the case study of Nothrotheriops shastensis (Xenarthra, Tardigrada, Nothrotheriidae)

The utility of orthodentine microwear analysis as a proxy for dietary reconstruction in xenarthrans (tree sloths, armadillos) was quantitatively and statistically accessed via low‐magnification stereomicroscopy. Features such as number of scratches and pits, as well as presence of gouges, hypercoarse scratches, > four large pits, > four cross scratches, and fine, mixed or coarse scratch texture were recorded in 255 teeth from 20 extant xenarthran species. Feature patterns are consistent with scar formation through abrasional (tooth–food) and attritional (tooth–tooth) contact. Number of scratches is the most dietary diagnostic microwear variable for xenarthrans, with herbivorous sloths characterized by > ten scratches and nonherbivorous armadillos by