Aquatic nematodes from Ethiopia II

Abstract

Eight species of the genus Monhystrella, six of which are new to science, are described from bottom samples collected from three lakes, two rivers and a hot spring in Ethiopia. Monhystrella hoogewijsi n. sp. is identified by a distinctive bulge on the lip region, position of the amphids, offset and well developed single pharyngeal terminal bulb, tail shorter than vulva-anus distance, tail elongate-conoid for two-thirds of its length, and by the shape and size of the spinneret outlet; M. jacobsi n. sp. by its slender body, distinctively offset and distended lip region, indistinct and weakly expanding single terminal pharyngeal bulb, and shape and size of the tail and spinneret outlet; M. arsiensis n. sp. by its single terminal pharyngeal bulb, position of amphids, shape and length of tail and spinneret outlet; M. woitorum n. sp. by its hemispherical lip region, double terminal pharyngeal bulb, shape and length of the spinneret outlet, and shape and length of tail; M. ethiopica n. sp. by its bipartite stoma, size of amphid in relation to corresponding body width, filiform tail and shape and length of spinneret outlet. M. atteae n. sp. differs from all known Monhystrella species in having an inflated cap-like lip region and fine crystalloid bodies. M. macrura (de Man, 1880) Andrassy, 1981 and M. lepidura altherri (Juget, 1969) Jacobs, 1987 are reported from Ethiopia for the first time. Crystalloid bodies in the genus Monhystrella is reported here for the first time. Also the presence of a hyaline coelomocyte next to the germinal zone of the reproductive system is reported for the first time in the genus here in all eight species. The structures used in the taxonomy of the genus are reviewed.