Unique occurrence of large-sized diamondback squid Thysanoteuthis rhombus (Troschel, 1857) in the Gulf of Mannar

The presence of the large-sized diamondback squid Thysanoteuthis rhombus (Troschel, 1857) in the Gulf of Mannar biosphere was confirmed after a two-decade absence, based on a single specimen observed during landings at the Pamban lighthouse Fish Landing Centre. A squid measuring 633 mm in mantle length and weighing 15.1 kg was caught in the hook and line at a depth of 20 m. The discovery of this species in the Gulf of Mannar unequivocally confirms that the population is still present in the ecosyste