A giant squid (Architeuthis dux) off Reunion Island, western Indian Ocean: the greatest giant ever?

Abstract

A freshly dead individual of the giant squid Architeuthis dux, presumably mutilated by a predator of bigger or comparable size, is reported from the south-western Indian Ocean in proximity to Reunion Island. The species was identified from body and beak morphology and validated genetically. The dorsal mantle length (DML) estimated from beak measurements (lower rostral length, LRL) varied between 2153 and 3060 mm depending on the allometric equation used. The Architeuthis dux individual described here is the biggest giant squid ever reported for the region.

How old are giant squids? First approach to aging Architeuthis beaks

“…The higher occurrence of findings in this season could be influenced by exposition to warm water currents, because it has been suggested that giant squids may suffocate from arterial desaturation when high increases in ambient temperatures are experienced (Brix 1983). Recent studies (e.g., Romanov et al 2017) support the observations made in the present study of severe mutilations due to predation on the specimens recovered from the sea surface, and injuries at the mantle tip suggest predation by a large animal, probably a sperm whale. Eight of the ten individuals of the present study were found in the southwest of Tenerife Island, an area with a steep deepwater canyon in the channel between the islands of Tenerife and La Gomera, hosting a resident population of shortfin pilot whales Globicephala macrorhynchus Gray, 1846.…”

Ficha de Architeuthis dux

“…Architeuthis dux é o maior cefalópode (e molusco) conhecido (em peso) e, provavelmente, o maior invertebrado marinho. Os maiores exemplares atingem até 5 m de comprimento do manto (CM) e comprimento total (CT) de 18-20 m, sendo a maioria dos registros entre 6 e 12 m de comprimento total (Roper, 2016;Romanov et al, 2018). É uma espécie semelpárea, reproduzindo-se uma vez na vida.…”

“…A espécie parece estar associada à cânions submarinos na margem continental no Brasil e em outras localidades do mundo (Martins & Perez, 2009;Guerra et al, 2011). Atinge cerca de 20 m de comprimento total (Romanov et al, 2018).…”