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Identifier

000448967

Title

Στοιχεία μορφολογικής αναγνώρισης και βιολογίας ενός νέου ξενικού είδους κεφαλοπόδου του γένους Sepioteuthis

Alternative Title

Morphological identification and biology of a new alien cephalopod species of the genus Sepioteuthis

Author

Αλ Μπελμπέισι, Ρούλα O.

Thesis advisor

Τσερπές, Γιώργος

Reviewer

Κουμουνδούρος, Γιώργος
Σωμαράκης, Στυλιανός

Abstract

Recently, a cephalopod species of the genus Sepioteuthis has entered the Eastern Mediterranean from the Red Sea, via the Suez Canal. This species, also known as ‘soupiocalamaro’ in Greece, was first recorded off the coast of Turkey in 2002 and it is, until now, the only Lessepsian squid migrant in the Mediterranean. Based on its morphological characteristics, previous researchers identified it as Sepioteuthis lessoniana, a species widely distributed in the Indo-Pacific Ocean and the Red Sea. It is indicated that S. lessoniana comprises a cryptic species complex, which consists of multiple distinct genetic clades, with little or no morphological differences. In the Red Sea, two distinct genetic groups of the species were found, one of which, S. cf. lessoniana, has a large genetic distance from the previously reported clades. S. cf. lessoniana was genetically identified with samples collected in Crete, as well. Despite the particular interest in the S. lessoniana species complex, research has been limited to its molecular analysis, and there are no morphological descriptions of the individual genetic clades. Thus, in the present study, S. cf. lessoniana of Crete is morphologically described and a number of morphometric indices for all Sepioteuthis species are compared. In addition, elements of the species biology and ecology in the new environment are studied. For the present work, numerous morphometric and meristic measurements were taken, while morphometric and biological data were analyzed for 93 individuals of the species collected in Crete. The morphological description of S. cf. lessoniana was more in line with the already known descriptions of S. lessoniana species, while the position of the maximum width of the mantle, the number of the buccal mass’s suckers, and the shape of the fin (only in a few individuals) differed significantly. Moreover, it is shown that sexual dimorphism in the shape of body structures occurs, with e.g., females significantly exhibiting greater gladius width than males. The spawning season seems to last the whole year round with a peak in spring. Mature individuals were collected during the whole year, while immature ones were only found in autumn and winter. All males collected in spring were reproductively mature. The stomach contents were analyzed through metabarcoding using two barcodes, 16S and CO1. The diet consisted of 9 different species of fish and one species of ascidians, the majority of which were benthopelagic and common in depths up to 100 m.

Language

Greek

Subject

Crete

Lesseptian migrant

Morphology

Κρήτη

Λεσσεψιανή μετανάστευση

Μορφολογία

Issue date

2022-07-29

Collection