North-eastern Atlantic Amphipoda: Aoridae

R. King & A.A. Myers

Lembos websteri Bate, 1857

Lembos websteri Bate, 1857: 142. --Chevreux & Fage, 1925: 303, fig. 313. --Myers, 1979b: 256�263, figs.192�195. --Myers, 1982a: 127, fig. 84.

Microdeutopus websterii (sic). --Bate, 1862: 164, pl. 30, fig. 2.

Microdeutopus bidentatus Stebbing, 1876: 73, pl. 4 fig. 1a, pl. 5 figs. 1, 1b.

Autonoe longipes (partim). --Della Valle, 1893: 403, pl. 3 fig. 13, pl. 10, figs. 20�30 (non L. longipes (Liljeborg, 1852): 10).

Autonoe websteri. --Sars, 1894: 547, pl. 194.

Type material. Unknown.

Type locality. Falmouth, Devon, England.

Description. Based on Myers, 1982a: 127, fig. 84; Myers, 1979b: 256�263, figs.192�195.

Head. Rostrum absent or vestigial; Lateral cephalic lobes apically round, anteroventral margin moderately excavate, scarcely recessed. Antenna 1 flagellum with 20 or less articles; accessory flagellum present and multiarticulate. Antenna 2 with few long setae. Labium with fine setae and stout setae. Maxilla 1 inner plate with 1 long pectinate apical seta. Maxilliped basis with strong flange on anterior margin; palp with wing-like flanges on anterior margin of basis, ischium and merus. Mandible, palp article 3 longer than 2, posterior margin strongly falcate or widest medially, mandible palp posterior margin setae of more than two distinct lengths.

Peraeon. Sternal spines present, on other pereonites, apically acute. Gnathopod 1 enlarged in males only; coxa distinctly produced anterodistally, acute; basis robust, half or more as broad as long, without a spine, anterior margin without stridulating ridges, posterodistal margin with setae sparse or absent, anterodistal margin with flange weak or absent, with a weak distomedial lobe or absent; ischium anterior margin without flange, posterior margin with setae sparse or absent; merus not greatly elongated, fused along its entire length with carpus, posterior margin with dense rows of setae, without posterodistal spine; carpus two thirds length of propodus, anterior margin without stridulating ridges, with long dense setae, anterior surface with no spine, without an oblique row of long setae on medial face, posterior margin without spines; propodus longer than carpus, anterior-distal margin densely clothed in long setae, posterior margin straight or evenly convex, palm present, palm delimited from posterior margin, margin forming a narrow sinus, palm defined by strong posterodistal spine, with robust seta defining palm, without spine near base of dactylus; dactylus less than half length of propodus, significantly overlapping palm. Gnathopod 2 subchelate; basis anterodistal margin with flange, posterodistal margin without robust setae; with few setae along length of basis; carpus subequal with or shorter than propodus, anterior margin not lobate, densely setose; propodus densely setose, palm with robust seta(e) defining palm. Pereopod 6 basis not or weakly produced posterodistally. Pereopod 7 significantly less than 125% length of pereopod 6.

Pleon. Epimeron 3 posterodistal margin rounded. Uropod 1 biramous, rami rami subequal, peduncle much longer than broad, distoventral interramal spine shorter than peduncle. Uropod 2 peduncle with distoventral interramal spine. Uropod 3 biramous, outer ramus shorter than inner, inner ramus subequal with length of peduncle. Telson with distal fine setae only.

Habitat. Among algae, phanerogams, hydroids, polyzoans, sponges, oysters etc. (Myers, 1982a).

Depth zones. Littoral.

Distribution. Altantic Ocean, Mediterranean Sea.

(Variant) Female (sexually dimorphic characters).

Peraeon. Sternal spines absent. Gnathopod 1 coxa distinctly produced anterodistally, sub-acute; posterior margin with sparse setae or setae absent; with setae sparse or absent; anterior margin weakly to moderately setiferous, palm evenly continuous with posterior margin, margin entire, palm defined by rounded or oblique corner or corner undefined; dactylus about half length of propodus, fitting palm. Gnathopod 2 basis anterodistal margin without flange; moderately to sparsely setiferous; propodus moderately to sparsely setose.

Cite this publication as: 'King, R. & A.A. Myers (2001 onwards). North-eastern Atlantic Amphipoda: Aoridae. Version 1: 1 September 2001.'. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).