Tiaricodon Orientalis Sp. Nov., A New Species (Hydrozoa, Anthoathecata, Halimedusidae) From Sagami Bay, Eastern Japan

A new hydromedusa belonging to the order Anthoathecata is reported from Sagami Bay, eastern Japan. Tiaricodon orientalis sp. nov. can be distinguished from other Tiaricodon species by the umbrella size of the medusa, manubrium length, interradial peaks in the subumbrella, and a red band on the upper part of the manubrium. A comparative table of the primary diagnostic characters of the genus is provided. Our morphological and molecular phylogenetic analyses suggest that Tiaricodon from China is not Tiaricodon coeruleus but Tiaricodon orientalis.