Pacific Science, Volume 61, Number 1, 2007

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    New Species of Extinct Rails (Aves: Rallidae) from Archaeological Sites in the Marquesas Islands, French Polynesia.
    (Honolulu, University of Hawaii Press, 2007-01) Kirchman, Jeremy J. ; Steadman, David W.
    We examined 53 bones of rails (Rallidae), previously referred to Gallirallus n. spp., from archaeological sites on four islands in the Marquesas Islands, French Polynesia. We describe three new, extinct, flightless species of Gallirallus: G. roletti (Tahuata), G. gracilitibia (Ua Huka), and G. epulare (Nuku Hiva). Two bones from Hiva Oa, although probably representing another extinct species of Gallirallus, are regarded as an inadequate basis for describing a species. At first human contact, the genus Gallirallus probably included many scores if not hundreds of flightless species on islands from the far western Pacific (Okinawa, Philippines, Halmahera) eastward across most of Oceania. As currently understood, the Marquesas Islands represent the eastern range limit of Gallirallus.
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    Redescription of Yirrkala g jellerupi, a Poorly Known Freshwater Indo-Pacific Snake Eel (Anguilliformes: Ophichthidae).
    (Honolulu, University of Hawaii Press, 2007-01) McCosker, John E. ; Boseto, David ; Aaron Jenkins
    Yirrkala g jellerupi (Weber & de Beaufort, 1916), unknown since the brief and unfigured original description of the holotype from New Guinea, is herein diagnosed, described, and illustrated, based on specimens recently captured in a Fijian freshwater stream. Other eels collected there and nearby include Anguilla megastoma, A. obscura, Lamnostoma kampeni, and an unidentified moringuid. Living far from the sea is very atypical for an adult ophichthid.
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    Laboratory Observations of Reproduction in the Deep-Water Zoarcids Lycodes cortezianus and Lycodapus mandibularis (Teleostei: Zoarcidae).
    (Honolulu, University of Hawaii Press, 2007-01) Ferry-Graham, Lara A. ; Drazen, Jeffrey C. ; Veronica Franklin
    The first observations of reproduction and associated behaviors in captive bigfin eelpout, Lycodes cortezianus, and pallid eelpout, Lycodapus mandibularis, are reported here. One Lycodes cortezianus pair produced 13 transparent and negatively buoyant eggs that were approximately 6 mm in diameter. These were laid on a hydroid-covered rock. The development period was about 7 months, and the young that emerged were approximately 2 cm in total length. An additional captive pair also exhibited mating behavior as the male repeatedly nudged the female and the pair produced a burrow under a sponge; however the male died before any mating. Two gravid female Lycodapus mandibularis were captured and laid between 23 and 46 eggs that were about 4 mm in diameter. These were released on the sandy substrate after the females moved the sand about the tank, and the eggs were negatively buoyant. These eggs were all unfertilized. Additional burrowing behavior was observed from other captive individuals, but no eggs were subsequently produced. Taken together, our observations suggest that burrowing or use of other protective structures is a reproductive behavior of central importance to zoarcids. Contrary to some earlier hypotheses, even midwater species likely return to the sediment to burrow and/or deposit eggs. This behavior means that field data regarding reproduction in this family will continue to be difficult to obtain, and the contribution of further study in laboratory situations should not be underestimated.
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    Age and Growth of the Finescale Triggerfish, Balistes polylepis (Teleostei: Balistidae), on the Coast of Mazatla´n, Sinaloa, Mexico.
    (Honolulu, University of Hawaii Press, 2007-01) Barroso-Soto, Ithandehui ; Castillo-Gallardo, Emerita ; Quinonez-Vela´zquez, Casimiro ; Mora´n-Angulo, Ramo´n E.
    To estimate the weight-length relationship, determine age, and describe growth of the finescale triggerfish, Balistes polylepis Steindachner, 1876, 552 specimens were measured and weighed, and 318 first dorsal spines were collected from the artisanal catch in Mazatla´n, Sinaloa, Mexico, between October 2000 and October 2001. Fish ranged between 16 and 53 cm in total length (TL), and distribution was biased toward small sizes. Age was assigned according to the number of opaque-hyaline bands in spines, identifying seven age groups (1–7), with age groups 2, 3, and 4 jointly representing over 80% of the collection. The von Bertalanffy model was adequately fitted to the age-TL data and accounted for 91% of the variation in TL. Parameters were estimated as TLy ¼ 55:8 cm; K ¼ 0.17 yr_1, and t0 ¼ _1:7 yr. The total weight (TW) of the finescale triggerfish ranged between 75 and 2,200 g, and the TW-TL relationship showed a negative allometric growth ðb ¼ 2:7Þ. These results are the first reported for age and growth of this species.
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    Feeding Preferences of Acanthaster planci (Echinodermata: Asteroidea) under Controlled Conditions of Food Availability.
    (Honolulu, University of Hawaii Press, 2007-01) Pratchett, Morgan S.
    Feeding preferences of the crown-of-thorns sea star, Acanthaster planci (L.), were studied in a series of laboratory-based feeding trials wherein sea stars were provided with equal availability of six different coral species. The order in which corals were consumed was then used to ascertain feeding preferences. Crown-of-thorns sea stars exhibited strong and consistent feeding preferences across replicate feeding trials. The most readily eaten coral species was Acropora hyacinthus, followed by A. gemmifera, A. nasuta, A. formosa, Stylophora pistillata, Montipora undata, and Pocillopora damicornis. Crown-of-thorns sea stars also consumed Goniopora lobata, Fungia fungites, Goniastrea retiformes, and Pavona cactus but only after all Acropora and Montipora (Family Acroporidae) as well as Pocillopora and Stylophora (Family Pocilloporidae) were eaten. The leastpreferred corals were Favites abidita, Porites lobata, Symphyllia recta, Echinopora horrida, and Porites cylindrica. Of these, P. cylindrica was never eaten in any of the feeding trials in which it was offered. Observed feeding preferences substantiate findings from previous studies, where corals from the families Acroporidae and Pocilloporidae were preferred over all other corals. Further research is required to assess the underlying basis of feeding preferences of A. planci, but this study confirms that these starfish readily distinguish between different corals and have innate preferences for certain species. Still, most corals were eventually consumed, showing that when food is limited (during population outbreaks) A. planci is likely to consume virtually all different coral species, causing extreme devastation to coral reef ecosystems.