The first record of Gnathostenetroididea Kussakin, 1967 from Australian waters with description of four new species of Gnathostenetroides Amar, 1957 (Crustacea: Isopoda: Asellota) from the Great Barrier Reef Author Malyutina, Marina V. Author L. Bruce, Niel text Zootaxa 2019 2019-02-11 4554 2 301 350 journal article 27574 10.11646/zootaxa.4554.2.1 f2fd53f0-4029-4df6-bd91-d9b2ea0fc8c2 1175-5326 2623588 24BF4E57-F9EA-440C-8D07-069A0756FBC0 Family Gnathostenetroididae Kussakin, 1967 Diagnosis: Body with subparallel lateral margins, cephalon with rostral projection of varying size; eyes, if present, dorsolaterally rounded, of 3–8 ommatidia. Pleon subequal in size to two posterior pereonites, two pleonites anterior to pleotelson. Pereopods 1–4 inserted anteriorly, bases directed posteriorly; dorsal margin of pereopod articles oriented anteriorly. Pereopods 5–7 inserted posteriorly, bases directed anteriorly; dorsal margin of pereopod articles oriented posteriorly. Pereopods 2–7 dactylus with two strong, subequal claws. Pereopod 1 largest, subchelate, with broad enlarged prododus. Pereopod 1 of male longer and more stout than in female. Penes tubular, inserted from coxae of pereopods 7. Pleopod 1 of male longer than branchial cavity, covering remaining pleopods; protopod short, fused, rami separate, broad, lamellar. Pleopod 2 of male separate, less than half pleopod 1 length, exopod short, stout, inserting distomedially on protopod; copulatory stylet of endopod widening distally to setal fringed structure. Female pleopod 2 fused, covering remaining pleopods. Pleopod 3 endopod with 3 distal plumose setae; exopod elongate, slender. Pleopod 4 biramous, pleopod 5 uniramous. Uropods inserted ventrally adjacent to anus, protopod stout, rami relatively well developed. Anus not covered by pleopods, separated from pleopod chamber by preanal bar. Remarks . The Gnathostenetroididae can be identified and distinguished from the Protojaniridae by the presence of two free (unfused) pleonites, while Protojaniridae is characterized by absence of free pleonites.