North-eastern Atlantic Amphipoda: Aoridae

R. King & A.A. Myers

Autonoe longipes (Liljeborg, 1852)

Gammarus longipes Liljeborg, 1852: 10.

Autonoe longipes. --Bruzelius, 1859: 28. --Sars, 1895: 549, pl. 195. --Norman, 1895: 490.

Microdentopus longipes. --Bate, 1862: 166.

Lembos longipes Stebbing, 1895: 207. --Stebbing, 1906: 597. --Chevreux & Fage, 1925: 304. --Lincoln, 1979: 492, fig. 236. --Myers, 1979b: 249-256, figs. 187-191.

Autonoe plumosa Boeck, 1871: 239.

Type material. Unknown.

Type locality. Unknown.

Description. Based on Myers, 1979b: 249-256, figs. 187-191.

Head. Rostrum absent or vestigial; Lateral cephalic lobes apically round, anteroventral margin shallowly excavate, moderately recessed. Antenna 1 flagellum with 20 or less articles; accessory flagellum present and multiarticulate. Antenna 2 with few long setae. Labium with fine setae only. Maxilla 1 inner plate with 1 long pectinate apical seta. Maxilliped basis without strong flange on anterior margin. Mandible, palp article 3 subequal to 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 brush of long setae, anterodistal margin with strong flange, with a weak distomedial lobe or absent; ischium anterior margin with rounded or acute flange, posterior margin with setae sparse or absent; merus not greatly elongated, fused along its entire length with carpus, posterior margin with sparse setae or setae absent, 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 or margin forming a broad excavate sinus, palm defined by strong posterodistal spine, with robust seta defining palm, with spine near base of dactylus, with subtriangular, apically acute spine; dactylus about half length of propodus, fitting palm. Gnathopod 2 subchelate; basis anterodistal margin with flange, posterodistal margin without robust setae; with few setae along length of basis; carpus longer than propodus, anterior margin not lobate, densely setose; propodus densely setose, without robust seta or spine defining palm. Pereopod 6 basis not or weakly produced posterodistally. Pereopod 7 significantly greater 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, rami subequal, inner ramus one and one half times length of peduncle. Telson with distal fine setae and robust setae.

Habitat. Unknown.

Depth zones. Littoral, or Continental shelf, or Continental slope.

Remarks. Found at about 20-375 metres (Lincoln, 1979).

Distribution. North Atlantic, North Sea, Arctic Ocean, European coasts from north west Norway to north west France (Lincoln, 1979).

(Variant) Female (sexually dimorphic characters).

Peraeon. Sternal spines absent. Gnathopod 1 basis slender, much less than half as broad as long, posterodistal margin with setae sparse or absent; with setae sparse or absent; anterior margin weakly to moderately setiferous, margin entire, palm defined by rounded or oblique corner, without spine near base of dactylus; dactylus more than half length of propodus, significantly overlapping palm. Gnathopod 2 basis anterodistal margin without flange; carpus subequal with or shorter than propodus, moderately to sparsely setiferous; propodus moderately to sparsely setose, palm with robust seta(e) defining palm.

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).