Mezhov B.V. 2004. Three new species of the genus Macrostylis G.O. Sars, 1864 (Crustacea: Isopoda: Macrostylidae) from the Indian Ocean // Arthropoda Selecta. Vol.12 (for 2003). No.2: 95–100 [in English].
Zoological Museum of the Moscow State University, Bolshaya Nikitskaya Str. 6, Moscow 125009 Russia.
ABSTRACT. Three species of the genus Macrostylis G.O. Sars, 1864, new for science, are described from the abyssal zone of the Indian Ocean. M. expolita sp.n. (14°33’–16°09.3’N, 56°54’–92°37.1’E; 2478–2519 m) differs from the related M. foveata Mezhov, 2000 by strong setation of the body, the number and shape of the excavations on the tergites, the posterolateral processes of tergite IV, the shape of the pleotelson, the presence of three spines and a hook-like frontal spine on the sternal surface of the pereon’s anterior division, the shape and setation of operculum. M. latiuscula sp.n. (26°19.5’S, 89°59.5’E; 4730–4808 m) differs from other representatives of the genus by the following combination of characters: the comparatively wide body, the shortened pleotelson, the presence of the original tubercles on the sternal surface of the pereonal anterior division, the short antennae II, the rather poorly advanced pereopod III and the elliptical operculum. M. lacunosa sp.n. (2°03.2’S, 86°44’E; 4706–4737 m) differs from other species of the genus by the combination of the narrow, oblong body and pits on the head, the tergites and pleotelson without any setation, the single sternal spine, the short antenna II, the elongated narrow tooth process of the mandible, the broadened fourth article of the maxillipedal palp and the short, wide operculum.
KEY WORDS: Isopoda, Macrostylis, new species, abyssal zone, Indian Ocean.