First report of Gongylonema sp. in a free ranging callitrichid from the Brazilian Atlantic Forest: case report

This is the first report of parasitism by Gongylonema sp. in a free-ranging callitrichid from the Atlantic forest of Espirito Santo, Brazil. A juvenile male of Geoffroy's marmoset (Callithrix geoffroyi) was euthanized due to poor prognosis, then necropsied. Samples of the tongue were collected for routine histological processing. Microscopically, there were transversal sections of adult nematodes within the epithelial layer of the mucosa of the tongue. Lingual scraping demonstrated a small number of oval embryonated eggs with a thick capsule. The morphology of the adult parasites and the eggs, associated with its location, were compatible with the Spirurida nematode of the genus Gongylonema. Further studies are needed to evaluate the impact of this parasite on free-ranging callitrichid populations.