Alexandrella subchelata Holman and Watling, 1983

Berge, Jørgen & Vader, Wim, 2005, The amphipod genus Alexandrella (Amphipoda, Stilipedidae): taxonomic status, allometric growth and description of two new species, Journal of Natural History 39 (17), pp. 1327-1346 : 1344-1345

Alexandrella subchelata Holman and Watling, 1983

( Figure 10 )

Alexandrella subchelata Holman and Watling 1983, p 42 .

Alexandrella subchelata: Barnard and Karaman 1991, p 703 .

Material examined

Immature 11 mm, 49 ° 409S, 178 ° 539W, 103 m, collected on the RV Eltanin, 3 January 1967, cruise 27, station 1880 ( USNM); immature 8 mm, 41 ° 569S, 160 ° 079E, 4846– 4929 m, collected on the RV Eltanin, 8 December 1966, cruise 26, station 4 ( USNM); immature 6 mm, 65 ° 209400S, 54 ° 149110W, 1123 m, collected on the RV Polarstern, 7 March 2002, cruise 61 ( ANDEEP II), station 133-3, epibenthic sledge .

Distribution

All material of this species has been collected from the South Pacific, except for one specimen from the Weddell Sea (see below) .

Remarks

All three examined specimens were immature, and generally fit the original description by Holman and Watling (1983, p 44, Figures 6–8 ). The dorsal projections on pleonites 1–3, a character which seems to vary considerably within the genus, do, however, vary among the three specimens. The largest specimen (11 mm) closely resembles the figures of the holotype, whereas the second largest (immature 8 mm, from New Zealand) specimen possesses larger and more conspicuous acute projections dorsally on pleonites 1–3 (see Figure 10 ). The third examined specimen, collected in the Weddell Sea , does not possess any dorsal ridge on either pleonites 1 or 2 (as described from the type material and from the above-mentioned material), and the gnathopods are only weakly subchelate. However , due to the fact that all specimens are immature and that only scattered material from the Weddell Sea and the South Pacific is available, they are herein treated as all belonging to the same species .

Figures

Figure 6. Alexandrella mandibulata n. sp. Holotype.

Figure 7. Alexandrella martae n. sp. Holotype.

Figure 8. Alexandrella martae n. sp. Holotype.

Figure 10. Alexandrella subchelata. Upper: immature 8 mm, RV Eltanin, cruise 26, station 4. Lower: immature 6 mm, RV Polarstern, ANDEEP station 133-3.