A new species of box jellyfish, Carybdea wayamba sp. nov. (Cnidaria: Scyphozoa: Cubomedusae: Carybdeidae) from Sri Lanka

: A new species of box jellyfish, Carybdea wayamba sp. nov. is described here based on forty specimens collected from the south and northeast coasts of Sri Lanka, with the type location being Bonavista Reef, Galle Bay. This species is classified in the genus Carybdea due to the possession of a typical heart-shaped rhopaliar niche ostia with only one upper scale and epaulette-shaped gastric phacellae in the four corners of the stomach. This new species can be distinguished from other valid members of the genus Carybdea by the combination of the structure of the two velarial canal roots per octant with one broadly bi-forked velarial canal with narrow, lateral lobations on each root, and other morphological characters such as having typical knee-shaped pedalial canal bends without any appendages, and epaulette-shaped gastric phacellae with single-rooted, brush-shaped, multiple (three to five) short-stemmed, dendritically branched (both short and long branches) gastric filaments. This is the first novel cubomedusa described from Sri Lankan waters; and the first Carybdea species described with material from the North Indian Ocean.