Contribution to the bioecology of Abraliopsis morsii Verany, 1839 (Cephalopoda, Enoploteuthidae) off the Canary Islands

Abstract

In the Atlantic Ocean, Abraliopsis morisii (Vérany, 1839) is distributed along the tropical and subtropical zones. The species is relatively abundant and plays an important role in the trophic web of oceanic waters. The present work is based on individuals caught in 1997, 1999, 2000 and 2002 by the S/V La Bocaina, including two trawl series of 4 tows at four discrete levels during day and night times, using a commercial fishing gear. Sexual dimorphism was observed, being males smaller than 30 mm mantle length, while females reached larger sizes. The average number of ripe oocytes was 564 (range 420 - 692 oocytes), and the average number of spermatophores was 33, oscillating between 14 and 69. The length of the spermatophores ranged between 6.5 and 12 mm. This short life span species is abundant along the year around the islands. This species fed on small zooplankton. Squid showed nocturnal migrations to surface and the species was more abundant around eastern islands. This is the first contribution to the biology of Abraliopsis morissi in the Canary Islands zone, the northeast part of its distribution area.