Studies on the genus Axonchium cobb, 1920 from India

Abstract

Three new species of Axonchium, one each belonging to the subgenera Axonchium, Epaxonchium and Spiculaxonchium n. subgenus are described from India. The new subgenus Spiculaxonchium is similar to the subgenera Metaxonchium and Epaxonchium but differs from both in the shape of spicules and in having very weakly developed lateral guiding pieces and ventromedian supplements. Axonchium (Spiculaxonchium) spiculum n. sp. (L = 1.65-1.88 mm, V = 52-54) is similar to A. (M. ) vaginatum and A. (M.) leptocephalum. Axonchium (Axonchium) vallum n. sp. (L = 1.59-1.95 mm, V = 52-59, odontostyle = 10-12 μ m, odontophore = 13-14 μ m, spicules = 55-57 μ m) has only 1-3 ventromedian supplements and is similar to A. (A. ) siddiqii and A. (A. ) shamimi. Axonchium (Epaxonchium) tacitum n. sp. (L = 1.76-1.96 mm; V = 55-57, odontostyle = 10-12 μ m, odontophore = 15-16 μ m, spicules = 52-57 μ m, ventromedian supplements = 7-9) is similar to A. (E.) valvulatum. Males of A. (A. ) shamimi and A. (M.) vaginatum are reported for the first time. The latter species, which was originally described from a single female is redescribed.