Macarorchestia Stock, 1989

Wildish, David J., 2014, New genus and two new species of driftwood hoppers (Crustacea, Amphipoda, Talitridae) from northeast Atlantic and Mediterranean coastal regions, Zoosystematics and Evolution 90 (2), pp. 133-146 : 133

Taxon classification Animalia Amphipoda Talitridae

Genus Macarorchestia Stock, 1989

Macarorchestia Stock 1989: 1109; Ruffo 1993: 738.

Type species.

Macarorchestia martini Stock, 1989

Component species.

Currently includes five species: M. martini, M. roffensis, M. remyi, M. pavesiae sp. n., Macarorchestia microphtalma (Amanieu & Salvat, 1963) new comb.

Diagnosis.

As in Stock (1989) except that the lacinia mobilis of the left mandible is 4 - 5 -dentate. The propodus of the seventh peraeopod carries distinctive tufts of long, slender setae, which are sexually dimorphic. The first antenna with up to 5 articles (versus 3 in Stock). The pleopods are biramous with a basis which is not reduced, but both rami are variously reduced dependant on the total body length of the largest adults of the species. Thus in the smallest species, martini, there is no segmentation in the rami and 1-3 plumose setae and in the largest, microphtalma, there up to 5 segments and 11 plumose setae. The pleopod rami may be sexually dimorphic, as in male Macarorchestia remyi , and the second antennal flagellum articles are sexually dimorphic in female Macarorchestia pavesiae sp. n. In addition all species are small, that is to say < 15 mm in total body length and lack epidermal pigment patterns.