|Budget Amount *help
¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1992 : ¥600,000 (Direct Cost : ¥600,000)
Fiscal Year 1991 : ¥1,400,000 (Direct Cost : ¥1,400,000)
The polychaetous annelids of the family Polynoidae collected from world-wide hydrothermal vents and cold-seeps were studied. The collection was made by the Institute Francais de Recherche pour l'Exploitation de la Mer and Japan Marine Science and Technology Center. The sampling sites were : 1) White Lady site, North Fiji Basin, 2) Hine Hina and Vailili sites, Lau Basin, 3) Genesis and Totem sites, East Pacific Rise, 4) Snake Pit site, Mid-Atlantic Ridge, 5) Minami-Ensei Knoll, Izena Holl, and Iheya Ridge, Okinawa Trough, 6) Kaikata and Nikko Seamount, Izu-Ogasawara Ark System, 7) Hatsushima cold-seep site, Sagami Bay. The collection contained 13 species with a new subfamily, 3 new genera and 4 new species. Among them, only the species of the subfamily Branchipolynoinae were clearly divided in the geographical distribution. Branchipolynoe symmytilida distributes only in Atlantic waters, such as Gulf of Mexico and Mid-Atlantic Ridge. This species has large elytra and biramous parapodia with well-developed notopodia, and thus is thought to have primitive characters. Branchipolynoe seepensis distributes only in East Pacific areas, and Branchipolynoe pettiboneae occurs only in West Pacific areas. These two species have smaller erytra and subbiramous parapodia and thus are thought to have more advanced morphological characters. In the evolutionary process, the Pacific species group might be firstly divided from the stem species and then the two Pacific species may be divided each other. This process looks like well concordant with the geohistorical crustal movements, however we need more information on the animal community of the hydrothermal vents and cold-seeps of the world.