Abstract

Pyrosomes, belonging to the Pyrosomatidae family, are pelagic, colonial tunicates composed of thousands of zooids within a common, gelatinous tunic. They are known for their long-lived bioluminescence and occasional large-scale blooms. Pyrosoma atlanticum Peron, 1804 is the only representative of pyrosomes in the Mediterranean. On 9 February 2025, a single colony of P. atlanticum was observed during a scuba dive at a depth of 12 m in Mersin Bay, Türkiye. The present study reports an additional record for the pelagic tunicate P. atlanticum in the northeastern Mediterranean.

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