First record of pearlfish (Carapus acus) in the western Algerian coast

First record of pearlfish (Carapus acus) in the western Algerian coast

Karim Mezali, Ihcene Khodja

ORCID IDs: K.M. 0000-0002-7222-9002; I.K. 0000-0003-3905-974X

Protection, Valorization of Coastal Marine Resources and Molecular Systematics Laboratory, Department of Marine Science and Aquaculture, Faculty of Natural Sciences and Life, Abdelhamid Ibn Badis University – Mostaganem, PO Box 227, Route nationale N° 11, Kharrouba, 27000, Mostaganem, ALGERIA


Commensalism between the pearlfish Carapus acus and the holothurian Parastichopus regalis is one of the most common associations between vertebrate and an invertebrate in the Mediterranean Sea. Seven individuals of Carapus acus were found inside the Parastichopus regalis coelomic cavity at three stations off the western Algerian coast with a depth of between 53 and 117 m. The wet weight of these individuals varied from 1.24 to 4.11 g and the total length from 12.30 to 16.60 cm. These values and other morphometric characteristics of C. acus individuals were compared with those reported on the Tunisian and Moroccan coasts.

Keywords: Carapidae, Stichopodidae, commensalism, morphometrics, Algeria

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