Amphilochidae

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The key includes 17 of the 18 northeast Atlantic species: Apolochus brunneus (Della Valle, 1893) is excluded, as it is mostly Mediterranean, with a few uncertain registrations from the Atlantic side of Gibraltar.

About the key

Amphipods of the family Amphilochidae Boeck, 1871 are relatively small (mostly between 1 and 5mm length) and somewhat stout. They can often be recognised from the combined characters of small, pointed rostrum, elongate triangular and entire telson, biramous uropod 3 and large, rounded coxal plates 2 to 4, with coxa 2 covering most of the much smaller coxa 1 and coxa 4 being excavate posteriorly allowing the much shorter coxa 5 room. They are not very fast swimmers.

The family consists today of 14 genera, of which the two largest are considered possibly paraphyletic; thus the taxonomy is still uncertain for several of the included taxa.

The family is cosmopolitan, but the smaller genera seem to be fairly restricted geographically. In the northeast Atlantic 18 species from six genera have been registered, of which 16 have been found in Nordic and Nordic Arctic waters. When present, Amphilochidae can be quite abundant, and they can be found at all depths and in the entire temperature range of the area. Little is known about their ecology and life history.

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A collection of different species of Amphilocidae. Reykjanes Ridge, N Atlantic.

References

Boeck, A (1871) Crustacea Amphipoda Borealia et Arctica. Videnskaps Selskabets Forhandlinger, Kristiania, 1870: 1-222.

Boeck, A (1873) De skandinaviske og arktiske amfipoder. Christiania, 864 pp.

Brix, S et al (2018) Amphipod family distributions around Iceland. ZooKeys 731: 41-53.

Hoover, PM & Bousfield, EL (2001) The amphipod superfamily Leucothoidea on the Pacific coast of North America: Family Amphilochidae: Systematics and distributional ecology. Amphipacifica 3: 3-28.

Krapp-Schickel, G (1982) Family Amphilochidae. In: Ruffo, S (ed) The Amphipoda of the Mediterranean Mémoirs de l´Institut Océanographique 13: 70-93.

Lincoln, RJ (1979) British Marine Amphipoda: Gammaridea. British Museum (Natural History). London, 658pp.

Sars, GO (1890-95) Amphipoda. An Account of the Crustacea of Norway With Short Descriptions and Figures of Alle Species, 1. Al. Cammermeyer. Christiania, 717 pp.

Stephensen, K (1935) The Amphipoda of N. Norway and Spitsbergen with adjacent waters. Tromsø Museums Skrifter 3: 1-140.

Tandberg, AHS & Vader, W (2018) On a new species of Amphilochus from deep and cold Atlantic waters, with a note on the genus Amphilochopsis (Amphipoda, Gammaridea, Amphilochidae). ZooKeys 731: 103-134

Intro and key based on

Tandberg, AHS & Vader, W (2018) On a new species of Amphilochus from deep and cold Atlantic waters, with a note on the genus Amphilochopsis (Amphipoda, Gammaridea, Amphilochidae). ZooKeys 731: 103-134