Structural Characterization and Profiles of Saponins from Two Algerian Sea Cucumbers.

Sea cucumbers are benthic marine invertebrate members of the phylum Echinodermata. Due to the absence of a rigid skeleton, these species have developed chemical defenses based on the production of saponins (triterpene glycosides). These secondary metabolites are bioactive molecules with a broad biological, ecological, and pharmaceutical spectrum.

On the presence of Ocnus planci Brandt, 1935 (Echinodermata: Dendrochirotida: Cucumariidae) in the Mostaganem region (Western Algerian coast).

In Algeria, few studies have been carried on the Holothuriodea especially the family Cucumariidae Ludwig, 1894. A specimen was caught as bycatch from a commercial benthic trawler on the Mostaganem coast (northwest of Algeria). Based on a detailed study of the morphological, anatomical and endoskeletal characters, this specimen is confirmed to be Ocnus planci (Brandt, 1835).

Morphological distinction of the Ophioderma Müller & Troschel, 1840 species (Echinodermata: Ophiuroidea: Ophiacanthida: Ophiodermatidae) from the Algerian west coast.

Ophioderma longicaudum (Bruzelius, 1805) is a very common brittlestar in the Mediterranean Sea that had been considered as a complex of cryptic species since 2009. Recently, five species were separated from this complex, but they remain morphologically very close. The aim of this study is to attempt for the first time to identify the species of Ophioderma found at the Algerian west coast, using morphological and morphometric analysis.

First record of Luidia atlantidea Madsen, 1950 (Echinodermata: Asteroidea: Paxillosida: Luidiidae) in the Sidi-Medjdoub areaMostaganem (West Algerian coast, Mediterranean Sea).

The genus Luidia is currently represented in the Mediterranean Sea by three species, namely Luidia ciliaris (Philippi, 1837), Luidia sarsii sarsii (Dben Koren in Dben, 1844) and Luidia atlantidea (Madsen, 1950) which is an Atlantic species recently reported from the Spanish and Tunisian coasts. Two individuals of Luidia atlantidea were collected as bycatch from small-scale fisheries in the region of Sidi-Medjdoub (Mostaganem, Algeria) at a depth of 53 m. The detailed study of the morphological and anatomical characters allowed us to formally identify the two individuals of Luidia atlantidea and therefore to report it for the first time in the Algerian West coast.

Multiple records and polymorphism of Parastichopus regalis (Cuvier, 1817) (Echinodermata: Holothuroidea: Stichopodidae) along the Algerian coast.

The family Stichopodidae is represented in the Mediterranean Sea by the genus Parastichopus which includes two non-endemic species; Parastichopus tremulus (Gunnerus, 1767) and Parastichopus regalis (Cuvier, 1817). On the Algerian coast (southwestern Mediterranean Sea), two morphotypes of P. regalis were observed, one with dark spots on the dorsal surface and the other non-spotted.

On the taxonomic status of Holothuria (Holothuria) tubulosa (s.s.) from the Algerian coast with the description of a new Mediterranean species, Holothuria (Holothuria) algeriensis n. sp. (Echinodermata: Holothuroidea: Holothuriidae).

In this study we redescribe the taxonomy of some holothuriid species collected from different localities of the Algerian coastal waters. Morphological (anatomical and endoskeletal) and previous molecular studies show the presence of two distinct morphotypes of Holothuria (Holothuria) tubulosa "A" "B". Morphotype "A" corresponds to the classical Holothuria (Holothuria) tubulosa Gmelin 1791, described by Koehler (1921) and hereafter referred to as H.

Paraleptopentacta, a new Mediterranean and north-west Atlantic sea cucumber genus, with the first record of P. tergestina n. comb. (Echinodermata: Dendrochirotida: Cucumariidae) from the north-western Algerian coast.

The genus Leptopentacta H.L. Clark, 1938 is here reviewed and restricted to include only the type species and related tropical Pacific forms, while a new genus Paraleptopentacta is erected to accommodate the Mediterranean and some north-west Atlantic species, formerly assigned to Leptopentacta.