Metopa rubrovittata Sars, 1883

Krapp-Schickel, Traudl & Vader, Wim, 2015, Stenothoids living with or on other animals (Crustacea, Amphipoda), Zoosystematics and Evolution 91 (2), pp. 215-246 : 217-218

Taxon classification Animalia Amphipoda Stenothoidae

Metopa rubrovittata Sars, 1883 Figures 8, 9, 10B, C

Metopa rubrovittata Sars 1883: 90, t. 4, fig. 2, 2a; 1892: 255, pl. 89, fig. 2; Reibisch 1905: 31; Chevreux and Fage 1925: 127, fig., 125; Stephensen 1929: 5; Stephensen 1931: 189; Stephensen 1938: 175; Schellenberg 1942: 120, fig. 98; Gurjanova 1951: 432, fig. 276; Oldevig 1959: 44.

Type locality.

Christiansund (W Norway) and Vadsø (Finnmark)

Material examined.

-7 spec. in alcohol, 2 on slide: Surtsey (Vestmannaeyjar) off Iceland, 63.30 N, - 20.60 W. NA 30 m 18/8/1971 leg. Sigurdsson, det. J. Just. ZMUC-CRU– 4464.

-1 spec. 20/8/1971 same locality as above, ZMUC-CRU– 4465.

- 4 spec. North Sea without date, 4 spec., 57.266667 N 5.5 E. ZMUC-CRU– 4467.

Discussion.

It seemed strange that the sharp eye of Chevreux would have overlooked the synonymy between Metopa rubrovittata (cited by him in the same work Chevreux and Fage 1925: 127, fig. 125) and his newly erected Stenothoides latipes (loc. cit.: 129, fig. 127, 128), later transferred to Stenula and finally synonymized as Stenula rubrovittata (Sars, 1883) by Lincoln 1979. But until now really nobody had looked at the mouthparts of Metopa rubrovittata , an often cited species, which nevertheless is rarely found in Museum collections.

In fact, the studied material shows a classical mandible palp of Metopa species with 3 articles, though it has to be admitted that it was quite a difficult task to see always the articulations. But nevertheless, already the length of the mandible palp is very different in the material from the Channel (cf. Fig. 8 with Fig. 10B, C), thus it can be confirmed that Chevreux was right: both Metopa rubrovittata Sars, 1883 as well as Stenula latipes (Chevreux & Fage, 1925) do exist, and they show extremely similar body morphology, colour pattern and even ecological niche, only the mouthparts are somewhat different. Thus, Metopa rubrovittata Sars, 1892 is herewith revalidated and Stenothoides latipes (Chevreux & Fage, 1925) remains the type species of Stenula . It is not clear what the geographical distribution of the two species is, as all the numerous citations cannot be judged without examining their mandible.

For control Jean-Claude Sorbe sent us material from the Bay of Biscay, and the single specimen he had collected affirms this decision.