Notes to the Nematoda of the genus Heligmosomum Railliet et Henry, 1909 (Nematoda, Heligmosomidae) parasitizing Rodentia in Japan

Abstract

Performed is the analysis of the hitherto findings of Nematoda from the genus Heligmosomum Railliet et Henry, 1909 in Japan. It is stated that in Japan the members of two subgenera, namely Heligmosomum and Paraheligmosomum parasitize rodents. They are the following species: H. (H.) costellatum (Du-jardin, 1845), H. (P.) hasegawai Asakawa, 1987, H. (P.) yamagutii Chabaud, Rausch, Durette-Desset, 1963, H. (P.) asakawai N´Zobadila, Boyer, Durette-Desset, 1996, Heligmosomum (P.) mixtum Schulz, 1954, Heligmosomum (P.) sp. Asakawa, 1995. The key for determination of all above species is established Heligmosomidae, Heligmosomum, Rodentia, Japan, parasitic Nematoda The history of findings of parasitic nematodes from the genus Heligmosomum, parasitizing the rodents of Japan, is relatively short but though very complicated. The first finding was reported by Yamaguti (1954) who determined the Nematoda found as the species Heligmosomum costellatum. He was evidently influenced by the studies of Travassos and Darriba (1929) and Travassos (1937). Later on, Chabaud et al. (1963), on the new material, revised the conclusions by Yamaguti (1954) and described the new species Heligmosomum yamagutii. Another finding belongs to the species Heligmosomum halli (Schulz, 1926). The latter species is reported by Hasegawa and Otsuru (1981) from Japan from the host Microtus montebelli. This finding is questionable, because already earlier Desportes (1943) and later others (review in Tenora et al. 2002a, b) declared H. halli as the synonym of H. costellatum. Other case concerns the finding of Heligmosomum mixtum (cf. Asakawa and Satoh, 1987, Asakawa, 1995). N´Zobadila et al. (1996) judge about this finding that an incorrect determination of the new species Heligmosomum asakawai is concerned. Other questionable case is the finding of Nematoda determined by Asakawa (1995) as H. (P.) yamagutii. As well, the characteristics of a set of the known species from the subgenus Paraheligmosomum (review in Asakawa, 1995) (which is criticized in the study by N´Zobadila et al., 1996), indicates the necessity to make more precise the diagnosis of the latter subgenus. All this, already presented is the reason for critical evaluation of the hitherto findings from the genus Heligmosomum in Japan and for realisation of critical analysis. Ročník LII 3 Číslo 2, 2004 23