Time filter

Source Type

Chatan, Japan

Weese D.A.,Auburn University | Fujita Y.,University of Ryukyus | Fujita Y.,Marine Learning Center | Santos S.R.,Auburn University
Biological Bulletin

Archipelagos of the Indo-West Pacific are considered to be among the richest in the world in biodiversity, and phylogeographic studies generally support either the center of origin or the center of accumulation hypothesis to explain this pattern. To differentiate between these competing hypotheses for organisms from the Indo-West Pacific anchialine ecosystem, defined as coastal bodies of mixohaline water fluctuating with the tides but having no direct oceanic connections, we investigated the genetic variation, population structure, and evolutionary history of three caridean shrimp species (Antecaridina lauensis, Halocaridinides trigonophthalma, and Metabetaeus minutus) in the Ryukyu Archipelago, Japan. We used two mitochondrial genes-cytochrome c oxidase subunit I (COI) and large ribosomal subunit (16S-rDNA)- complemented with ge-netic examination of available specimens from the same or closely related species from the Indian and Pacific Oceans. In the Ryukyus, each species encompassed 2-3 divergent (9.52%-19.2% COI p-distance) lineages, each having significant population structure and varying geographic distributions. Phylogenetically, the A. lauensis and M. minutus lineages in the Ryukyus were more closely related to ones from outside the archipelago than to one another. These results, when interpreted in the context of Pacific oceanographic currents and geologic history of the Ryukyus, imply multiple colonizations of the archipelago by the three species, consistent with the center of accumulation hypothesis. While this study contributes toward understanding the biodiversity, ecology, and evolution of organisms in the Ryukyus and the Indo-West Pacific, it also has potential utility in establishing conservation strategies for anchialine fauna of the Pacific Basin in general. © 2013 Marine Biological Laboratory. Source

Clark P.F.,Natural History Museum in London | Fujita Y.,University of Ryukyus | Fujita Y.,Marine Learning Center | Ball A.D.,Natural History Museum in London | Ng P.K.L.,National University of Singapore

Traditionally, Crossotonotus spinipes (De Man, 1888) and Pseudopalicus serripes (Alcock & Anderson, 1895) were assigned to the Crossotonotinae Moosa & Serène, 1981, and Palicinae Bouvier, 1898, respectively. However, Ng et al. (2008:127) listed a number of major adult characters that suggested both subfamilies should be recognised as distinct families within the Palicoidea Bouvier, 1898 (see also Castro 2010, 2011; Guinot et al. in prep.). Recently, ovigerous specimens of C. spinipes and P. serripes were collected from Okinawajima and Kumejima, central Ryukyu Islands, Japan. The first zoeal stages of both species were hatched in the laboratory, dissected, examined, and the appendages illustrated and described. Crossotonotus spinipes first stage zoeas were distinguished by three characters: the absence of lateral carapace spines (present in P. serripes), abdominal somite 4 with a pair of dorsolateral processes directed ventrally (absent in P. serripes) and the presence of a small lateral spine on the telson (absent in P. serripes). These distinguishing features appear to support the recent division of the Palicoidea into two families. Copyright © 2012. Magnolia Press. Source

Komai T.,Natural History Museum and Institute | Fujita Y.,University of Ryukyus | Fujita Y.,Marine Learning Center | Maenosono T.,Kankyosha

Two species referred to the callianassid ghost shrimp genus Rayllianassa Komai & Tachikawa, 2008 are reported here-with. Additional locality records from Japan are provided for R. amboinensis (de Man, 1888), and the synonymy of Calli mass a ngochoae Sakai, 1999 with R. amboinensis is discussed. It is shown that R. amboinensis is associated with sponges or alcyonacean soft corals, representing unusual habitats for callianassids. Rayllianassa rudisulcus n. sp. is described on the basis of a single ovigerous female from shallow soft sediment in Ohura Bay, Okinawa Island, Ryukyu Islands. The new species is distinguished from R. amboinensis by the absence of a dorsal oval on the carapace, the antennal peduncle being longer than the antennular peduncle, and the different shape of the third maxilliped. The status of Rayllianassa is also briefly discussed. Copyright © 2014 Magnolia Press. Source

Komai T.,Natural History Museum and Institute | Fujita Y.,University of Ryukyus | Fujita Y.,Marine Learning Center

Three species of the processid shrimp genus Processa Leach, 1815, including two new species, are reported from shallow coastal waters in Okinawa Island, Ryukyu Islands, Japan: P. affinis Hayashi, 1975, P. filipes n. sp. and P. hayashii n. sp. The present specimens of P. affinis represent the rediscovery and range extension of this poorly known species, originally described from Indonesia. Male characteristics of P. affinis are documented for the first time. The two new species are referred to the P. aequimana Paulson, 1875 species group. Processa filipes n. sp. is characteristic in the greatly elongate fifth pereopod and the transverse ridge on thoracic sternite 8 consisting of soft cuticle. Processa hayashii n. sp. is charac-terized by the presence of a deep concavity on the anterolateral margin of the carapace just inferior to the antennal tooth. The number of species of Processa known from Japanese waters is raised from five to eight. Copyright © 2014 Magnolia Press. Source

Anthessius isamusi n. sp. is described based on female and male specimens from a turbinid gastropod, Turbo marmoratus Linnaeus, collected in the East China Sea off Kumejima Island, the Ryukyu Islands, southern Japan, during the KUMEJIMA 2009 Expedition. The female of the new species is differentiated from its congeners by the following combination of characters: 1) the absence of denticles on the ventral surface of the anal somite; 2) the length to width ratio of the caudal ramus; 3) the antenna bearing 4 claws; 4) the maxilla with 3 distal teeth; 5) the exopod of leg 4 with 3 spines on the terminal segment, and; 6) leg 5 with a rod-like terminal segment. Copyright © 2012. Magnolia Press. Source

Discover hidden collaborations