Coexistence of five Cercopithifilaria species in the Japanese rupicaprine bovid, Capricornis crispus.

The Japanese serow, Capricornis crispus (Bovidae, Caprinae, Rupicaprini), is parasitized by five Cercopithifilaria species: C. shohoi , recently described, and reexamined in this paper, C. multicaudan . sp., C. minutan . sp., C. tumidicervicata n. sp., and C. bulboidea n. sp. Coinfections are frequent. The location (skin or subcutaneous regions) in the host of adult worms differed between the species, as did many morphological characters of both adults and microfilariae. The location (limbs, trunk, etc.) in the host of adult worms and dermal microfilariae seemed to differ depending on the species. Male and female worms of the same species had similar head shapes, buccal capsules, and, in four species, swellings in the anterior region of the body (because of the presence of a giant ventral pseudocoelomocyte). The Cercopithifilaria spp. from C. crispus were related to the primitive forms of the genus, parasites of Bovidae and Cervidae, presently recorded in Africa and Europe. C. bulboidea was particularly close to the most primitive species, C. ruandae and C. dermicola , in Africa, with the pairs of caudal papillae numbered 8 and 9 being distant from each other, but the species also had several specialized characters. Like C. rugosicauda in a European cervid, the four other species had pairs 8 and 9 close to each other; they reflect an evolutionary trend (hypertrophy of pair 6, and reduction and posterior migration of pair 7) that suggests diversification in the host.