Macrostylis gerdesi (Brandt, 2002) Brandt, 2002

Riehl, Torben & Brandt, Angelika, 2010, Descriptions of two new species in the genus Macrostylis Sars, 1864 (Isopoda, Asellota, Macrostylidae) from the Weddell Sea (Southern Ocean), with a synonymisation of the genus Desmostylis Brandt, 1992 with Macrostylis, ZooKeys 57, pp. 9-49 : 37

Macrostylis gerdesi (Brandt, 2002) comb. n. Fig. 19

Desmostylis gerdesi Brandt, 2002, p. 616-626, Fig. 1-4.

Additions to original description.

Ventral spine in pereonite 1, directed onteriorly; ventral spines in pereonites 2-3 and 5-7, directed posteriorly. Pereonites 4-6 slightly constricted towards anterior margin.

Remarks.

Re-examination revealed spines on all sternites not illustrated before, except from pereonite 4. In the latter a ventral constriction is present close to the posterior margin. In Macrostylis gerdesi comb. n. long sensory terminal setae on dactyli and additionally long sensory setae on propodi of posterior pereopods are considered to be apomorphies for Desmostylis . The value of these characters to discriminate between genera is discussed above. However, a dactylus is present in pereopod 4 and in contrast to the Macrostylis obscurus comb. n. holotype, pereopod 3 ischium is triangularly expanded in Macrostylis gerdesi comb. n. As a consequence of the character discussion listed above this species is transferred the genus Macrostylis .