RESUMO
Micromorphological differences between hairs of the two-toed sloth (Choloepus hoffmanni) and of the three-toed sloth (Bradypus variegatus) were observed by means of scanning electron microscopy. Hairs of the two-toed had longitudinal grooves which exposed a uniform cortex when viewed in cross section. Hairs of the three-toed sloth have irregular transverse fissures and a cortex that contains scattered fusi. These morphological differences support the placement of the two sloth genera into separate families. Hairs of four other xenarthran species are also illustrated.
Assuntos
Cabelo/ultraestrutura , Bichos-Preguiça/anatomia & histologia , Xenarthra/anatomia & histologia , AnimaisRESUMO
The genus Chrysosphaerella, originally described by Lauterborn as having a single flagellum and later emended by Korshikov who observed a second flagellum, was studied using the electron microscope. Electron micrographs confirm Korshikov's observation ivhich in most recent classification schemes has been overlooked.