A New Genus and species of Box Jellyfish (Cubozoa: Carybdeidae) from Tropical Australian Waters

Abstract

A new genus and species of cubozoan is reported from the Northern Territory and Queensland. It possesses the following autapomorphic characters with respect to other known forms in the Tamoya/Irukandji group of carybdeids: a robust, matchbox-sized body; broad and overhanging pedalial inner wings; laminar-branching velarial canals; and qualitatively and quantatively unique nematocysts. Furthermore, while it shares some characters with other taxa in the group, it is unique in its combination of major morphological characters: like Tamoya, Carukia, Malo and 'Morbakka', it has frown-shaped rhopalial niche ostia; like Carukia, Malo and 'Morbakka', it has rhopalial horns, perradial lappets, and lacks gastric cirri; like Tamoya and 'Morbakka', it has a prominent thorn-shaped upwardpointing diverticulum near the base of the pedalial canal and greatly flared tentacle bases; like Malo and 'Morbakka', it has two rows of nematocyst warts on the perradial lappets; like Malo, the rhopaliar horns are short and broad. Its cnidome comprises Type 4 microbasic p-mastigophores on the tentacles, and spherical isorhizas on the bell. Recent molecular phylogenetic studies place it, along with 'Morbakka', intermediate between the Carukia clade and the Malo clade. It is considered a mild health risk to humans.