Macrostylidae Hansen, 1916

Brandt, Angelika, 2004, New deep­sea species of Macrostylidae (Asellota: Isopoda: Malacostraca) from the Angola Basin off Namibia, South West Africa, Zootaxa 448, pp. 1-35 : 2

Macrostylidae Hansen, 1916

Macrostylis Sars, 1864: 13 . —Beddard, 1886: 173. — Hansen, 1916: 75. — Wolff, 1956: 99. — Wolff, 1962: 91. — Menzies, 1962: 128. — Brandt, 1992: 69. — Mezhov, 1992: 83; 2000: 69; 2002: 3.

Type species: Macrostylis spinifera Sars 1864 (by monotypy).

Diagnosis: Body elongate, at least 3.0 as long as broad. Head broader than long. Antennule short or minute with 3–5 articles, with at least one thick distal aesthetasc, often more. Last peduncular article of antenna distally with one broom seta. Pars incisiva of mandibles slender, narrow, with 1–3 cusps, lacinia mobilis of left mandible very small, pars molaris with many setae at apex. Maxilliped palp of 5 articles, epipod long­oval, slen­ der, distally rounded. Pereopods subsimilar, pereopod 3 with ischium bearing large dorsal triangular lobe, with at least one stout, acute dorsal spine; pereopod 4 shortest. Female operculum oval, with setae at caudal tip; covering anus. Pleopod 5 present, uniramous. Uropod uniramous, ramus length one­third of sympod, distally with broom and sensory setae.

Gender feminine.

Remarks: The diagnosis of Macrostylis is revised drawing from earlier the diagnoses and descriptions of Sars (1864), Wolff (1956, 1962) and Brandt (1992) as well as the new species described here. Sars (1864) gave a Latin diagnosis for the monotypic genus, comparing Macrostylis to Eurycope , and pointed out that the typical shape of the posterior pereopods of Eurycope (swimming legs) were not present in Macrostylis . He also noted that species Macrostylis are smaller in size than those of Eurycope .

In the following diagnoses, only the supposed autapomorphic characters of the species are presented.