Akrophryxus, Williams & Boyko, 2021

Williams, Jason D. & Boyko, Christopher B., 2021, Out on a limb: novel morphology and position on appendages of two new genera and three new species of ectoparasitic isopods (Epicaridea: Dajidae) infesting isopod and decapod hosts, Zoosystema 43 (4), pp. 79-100 : 84

Genus Akrophryxus n. gen.

urn:lsid:zoobank.org:act:223FBBB0-B294-4C38-ADEA-37C5E561BCB0

TYPE SPECIES. — Akrophryxus milvus n. sp.

ETYMOLOGY. — The genus name is derived from the Greek prefix άκρο- (ákro-), meaning “limb” or “extremity” in reference to the specialization of the female of the species on the antennule of the host crab rather than on the host body, in combination with - phryxus, from the Boeotian prince Phryxus (Φρίξος) of Greek mythology, a common ending for dajid, as well as some bopyrid, genera. The gender is masculine.

INCLUDED SPECIES. — Akrophryxus milvus n. sp. (type species).

DIAGNOSIS. — Female. Body spheroid; cephalon externally indistinguishable from pereon. Antennules absent, antennae each as oblong flat plate lateral to oral cone. Maxillipeds ovate with recurved digitiform extension. Pereopods 1-5 subequal in size and shape. Oostegite 1 largest, broadly ovate with small posterior accessory lobe; oostegites 2/3, 4, 5 progressively larger; oostegite 2 thin and closely applied to oostegite 3. Pleon apparently modified as oblong, narrow, thickened plate with three circular medial holes: largest surrounding antennule of host, smallest hole at midpoint of plate, intermediate sized hole farthest from mouthparts of parasite.

Male. Cephalon fused with pereomere 1; cephalic slits present. Antennules of three stacked discs, flagella absent; antennae broad elongate lobes lateral to oral cone, flagella absent. Pereomeres 2-6 distinct; pereomere 7 fused with pleon, lateral margins recurved ventrally. Pereopods 1-6 subequal in size and shape; pereopod 7 lacking. Pleon rounded, all segments fused and fused with pereomere 7; pleopods lacking.

REMARKS

See Remarks below under Akrophryxus milvus n. gen., n. sp. for comparison of female and male characters of Akrophryxus n. gen., Telephryxus n. gen., and other dajid genera.