AnimaliaCerianthariaArachnactidaeStamparSérgio N.DidiSuraia O. ElPaulayGustavBerumenMichael L.A new species of Arachnanthus from the Red Sea (Cnidaria, Ceriantharia)Zookeys442018201874811010.3897/zookeys.748.22914 Arachnanthus Carlgren, 1912Diagnosis.

Arachnactidae with sterile protomesenteries; metamesenteries in duplets (M and B), long (‘M’) metamesenteries with gonads and a double mesenteric filament, short (B) betamesenteries sterile, with single, convoluted mesenteric filament; very long stomodeum; lacking a directive labial tentacle; cnidome with p-mastigophores and b-mastigophores (after Carlgren 1912, 1924, 1937 and den Hartog 1977).

Type species.

Arachnanthus oligopodus (Cerfontaine, 1891)

Valid species

Arachnanthus australiae Carlgren, 1937

Arachnanthus bockii Carlgren, 1924

Arachnanthus oligopodus (Cerfontaine, 1891)

Arachnanthus sarsi Carlgren, 1912

Arachnanthus lilith sp. n.

Distribution.

North Sea, Mediterranean Sea, Red Sea, East Australia, and Melanesia.

 CarlgrenO (1912) Ceriantharia. Danish Ingolf-Expeditie 5(3): 1–78. CarlgrenO (1924) Papers from Dr. Th. Mortensen´s Pacific Expedition 1914–16 XVI. Ceriantharia. Videnskabelige Meddelelser fra Dansk Naturhistorisk Forening 75: 169–195. CarlgrenO (1937) Ceriantharia and Zoantharia. Scientific Reports of the Great Barrier Reef Expedition 1928–29, 5: 177–207. den HartogJC (1977) Descriptions of two new Ceriantharia from the Caribbean Region, Pachycerianthus curacaoensis n. sp. and Arachnanthus nocturnus n.sp., with a discussion of the cnidome and of the classification of the Ceriantharia. Zoologische Mededelingen 51: 211–248.