Australian Amphipoda: Melitae

J.K. Lowry, P.B Berents & R.T. Springthorpe

Ceradocus (Denticeradocus) yandala Berents, 1983

Ceradocus (Denticeradocus) yandala Berents, 1983: 109, figs 7-8.

Type material. HOLOTYPE: male, 4.5 mm, AM P31718. PARATYPES: female, 4.0 mm, AM P31719; 3 specimens, AM P31720; 1 specimen, AM P31721.

Type locality. Fringing reef between Bird Islet and South Island, Lizard Island, Great Barrier Reef (14º 42'S 145º 28'E), reef rock, 12 m depth.

Description. Based on Berents, 1983: 109, figs 7-8. Head with anteroventral notch or slit, anteroventral corner with acute/subacute tooth. Antenna 1 longer than antenna 2; peduncular article 1 not geniculate with article 2, longer than article 2, with 2 robust setae along posterior margin; flagellum with 8 articles; accessory flagellum with 4 articles. Antenna 2 peduncular article 2 cone gland not reaching to end of peduncular article 3; article 4 subequal to article 5; flagellum with 5 articles. Mandible palp present, well developed, article 3 cone-like, setose on distomedial margin, subequal to article 1, article 2 longer than article 3, article 1 produced distally, shorter than article 2. Maxilla 1 inner plate with setae mainly terminal.

Pereon. Gnathopod 1 not sexually dimorphic; coxa anteroventral corner produced, acute, coxa posteroventral corner notch absent; merus without posterodistal tooth; carpus about 2 x as long as broad; propodus without anterodistal projection, posterodistal margin not swollen, palm acute, convex, defined by posterodistal corner, without posterodistal robust setae. Gnathopod 2 sexually dimorphic; subchelate; left and right gnathopods unequal in size; coxa posteroventral corner notch absent; (larger) merus with sharp posterventral tooth; palm angle nearly transverse, straight, defined by posterodistal tooth, with robust setae; dactylus apically blunt; palm convex, without posteroventral tooth. Peraeopod 6 propodus not expanded posterodistally. Peraeopod 7 basis with posterior margin smooth or minutely castelloserrate, posteroventral corner insignificant. Peraeopod 7 propodus not expanded posterodistally.

Pleon. Pleonite 1 with dorsal serrations, without dorsodistal spines, not dorsally bicarinate. Pleonite 2 with dorsal serrations, without dorsodistal spines, not dorsally bicarinate. Pleonite 3 with dorsal serrations, without dorsodistal spines, dorsally smooth. Epimeron 1 anteroventral corner without curved spine. Epimera 1-2 posteroventral margin with 1 to 2 large or small spines above spine defining posteroventral corner. Epimeron 3 posterior margin serrate, posteroventral corner subquadrate or with small acute spine, posteroventral margin serrate. Urosomite 1 without dorsal carina, without a small dorsal hump, not dorsally bicarinate. Urosomite 1 without posterodorsal spine. Urosomite 3 without dorsal robust setae. Uropod 1 peduncle without distoventral spur. Uropod 3 inner ramus shorter than outer ramus, or subequal in length to outer ramus. Telson cleft. Telson without robust setae on inner margins. Telson each lobe with 2 apical/subapical robust setae, apical conical extension reaching scarcely one third along longest seta.

Habitat. Marine; living in algae, coral rubble and reef rock.

Depth zone. Littoral (12 to 25 m).

Distribution. Queensland: Lizard Island, Great Barrier Reef (Berents, 1983).

Australian geographic areas. North-eastern Australia.

(Variant) Female (sexually dimorphic characters).

Description. Flagellum with 16 articles.

Pereon. Gnathopod 2 left and right gnathopods subequal in size; merus with sharp posteroventral tooth; carpus short; propodus without medial depression, palm acute, convex, sculptured, lined with robust setae, without posterodistal robust setae, defined by posteroventral tooth; apically acute/subacute.

Pleon. Remarks. This species closely resembles C. mahafalensis recorded from Madagascar by Ledoyer, 1979. The females have less spinous palms on gnathopods 1 and 2, the carpus and propodus of peraeopods 3-4 are less spinous, pleonites 1-3 have 9, 11, 14 teeth respectively and epimeron 3 has ventral margin bearing 2 teeth.

Cite this publication as: 'J.K. Lowry, P.B Berents & R.T. Springthorpe (2000 onwards). Australian Amphipoda: Melitae Descriptions, Illustrations, Identification and Information Retrieval. Version: 2 October 2000.'.