Longibrachium arariensis, a new species of Onuphidae (Annelida: Polychaeta) from the shallow water of Izu Peninsula, central Japan, with notes on its feeding behavior

A new species, Longibrachium arariensis, is described from shallow sandy bottoms, at the western side of Izu Peninsula, Shizuoka Prefecture, Pacific side of central Honshu, Japan. Longibrachium arariensis most closely resembles the Australian L. longipes Paxton, 1986 and European L. falcigerum Paxton and Gillet, 2004 in having a combination of large and small hooks in its prolonged parapodia. The new species can be distinguished from these two species by having shorter antennae and recurved hooks with differently arranged spines. This is the first record of the genus from Japan. We are reporting a unique collecting method of this large onuphid worm using hook and line and illustrating with underwater photographs the feeding behavior of the new species.