Magnapinna sp. A
Introduction
Magnapinna sp. A is based on a single specimen taken from the North Atlantic that was captured intact with damage only to the tips of the appendages. The holotype (US National Museum of Natural History cat. no. USNM xxxxxx), 59 mm ML, immature female, was captured in the Gulf of Mexico at 27°09’N, 86°07’W on 16 Sept., 1995.
Diagnosis
A magnapinnid with:
- Tentacle bases narrower than adjacent arm bases.
- Proximal tentacle without suckers but with glandular structures.
- Pigment mostly in functional chromatophores
Characteristics
- Arms
- Arms short, thick, weakly muscled and decreasing abruptly in diameter distally to form sucker-bearing filaments (mostly lost due to damage)
- Proximal-arms with suckers in two series (except at tips in some proximal-arms), ocasionally appearing slightly irregular.
- Tentacles
- Proximal-tentacles more slender than arms IV.
- Proximal- tentacles short, thin and without suckers; distal-tentacles (filaments) very narrow and bearing small suckers mostly around 0.08 mm in diameter.
- Distal third of proximal-tentacle with large, apparently glandular, lobes.
- Fins and tail
- Fins extremely large, about 90% of the mantle length.
- Fins appear not to have been drawn-out into V-shaped point.
- Tail presently a bare gladius with tip missing; extends at least 4 mm beyond fins.
- Pigmentation
- Head, mantle, funnel, collars and fins with numerous scattered chromatophores.
Comments
More details of the description can be found here.
Magnapinna sp. A differs greatly from M. pacifica in the much thinner tentacles, the lack of suckers on the proximal tentacles, the presence of large, glandular regions on the proximal tentacles, two sucker series on the arms rather than three to four and numerous other features. These differences are great enough to suggest that they may belong in separate genera. The thin, bare proximal-tentacles are shared with the other Atlantic species.
References
Fischer, H. and L. Joubin. 1907. Expéditions scientifiques du TRAVAILLEUR et du TALISMAN. Céphalopodes, 8: 313-353.
Hardy, A. 1956. The Open Sea. Fisher, J., J. Gilmour, J. Huxley, M. Davies, and E. Hosking, Eds., Collins, London, 1956.
M. Vecchione, R.E. Young, A. Guerra, D.J. Lindsay, D.A. Clague, J.M. Bernhard, W.W. Sager, A.F. Gonzalez, F.J. Rocha, and M. Segonzac. 2001. Worldwide observations of remarkable deep-sea squids. Science, 294: 2505-2506.
Vecchione, M., Young R. E. Submitted. The squid family Magnapinnidae (Mollusca; Cephalopoda) in the North Atlantic with a description of a new species.