TETRAPETALONEMA (T.) COLOMBIENSIS SP. N. (NEMATODA: FILARIOIDEA) FROM COLOMBIAN PRIMATES

Tetrapetalonema (T.) colombiensis sp. n., a filarial nematode from the subcutaneous and inter- muscular connective tissues of squirrel monkeys (Saimiri sciureus) and tufted ringtail monkeys (Cebus apella) from central Colombia is described. Tetrapetalonema colombiensis is a very small species (male 8 mm, females 11-21 mm), and within the subgenus most closely resembles T. panamensis and T. saimiri in dimensions and in general appearance. It can be distinguished from these species by the following major features: smoothly rounded profile of the anterior extremity; single pair of lateral caudal petals in the male; vagina vera directed immediately posteriad in the female; and a large (295-335 by 4.3-6.7 ,im) microfilaria that assumes a gently curved attitude in 2% aqueous formalin preparations (Knott's technique), and which has a conspicuous inner body. In the course of an investigation of the filariae of Neotropical primates, an outstandingly large microfilaria was observed in 2% aqueous for- malin concentrates of blood (Knott's technique) from squirrel monkeys (Saimiri sciureus) and tufted ringtail monkeys (Cebus apella) collected in certain areas of Colombia. This microfilaria