Cercopithecus, pen prod. Plin. A marmoset, or a munkey.
Lewis and Short: Latin dictionary
cercŏpĭthēcus, i, m., = kerkopi/qhkos, a monkey with a tail, Varr. ap. Non. p. 201, 26; Plin. 8, 21, 30, 72; Mart. 14, 202; 14, 128; divine honors were paid to it by the Egyptians, Juv. 15, 4.—Acc. cercopithecon, Mart. 7, 87, 4.—II.A proper name, Suet. Ner. 30.