title: Biology of the swimming acorn worm Glandiceps hacksi from the Seto Inland Sea of Japan.
abstract: The enteropneust hemichordate Glandiceps hacksi inhabits the muddy bottoms of the intertidal to subtidal zones of Koguno-shima Island, located in the central part of the Seto Inland Sea of Japan. Monthly collections from October 2005 to September 2007 revealed that their spawning occurs once a year, in the latter half of May. Parameters such as density and sex ratio, as well as the type of sediment, were also examined. Worm behavior and type of burrows revealed that G. hacksi are infaunal burrowers. Autotomy and regeneration of their posterior regions, and swimming behavior were also observed in an aquarium environment. This is the first comprehensive study on the biology of G. hacksi, the swimming acorn worm.
authors.affiliation: Marine Biological Laboratory, Graduate School of Science, Hiroshima University, 2445 Mukaishima-cho, Onomichi, Hiroshima 722-0073, Japan. urata@hiroshima-u.ac.jp
authors.forename: Makoto
authors.initials: M
authors.lastname: Urata
authors.forename: Sadaharu
authors.initials: S
authors.lastname: Iwasaki
authors.forename: Susumu
authors.initials: S
authors.lastname: Ohtsuka
mesh_terms: D000818:Animals; D017753:Ecosystem; D005260:Female; D019015:Geologic Sediments; D007448:Invertebrates / Q000502:physiology*; D007564:Japan; D008297:Male; D009792:Oceans and Seas; D012098:Reproduction; D013550:Swimming; D013997:Time Factors