A new species of Polymastia (Porifera, Hadromerida, Polymastiidae) from the Aleutian Islands, Alaska, USA

Polymastia fluegeli n. sp. is described from deep water off the Aleutian Islands (Alaska, USA). P. fluegeli is disc-shaped and lives partly buried in the sediment, with only the papillae protruding above the surface. This new species has a basal layer of agglutinated sediment particles occurring between the choanosome and the ectosomal lower layer. This conspicuous sediment layer is not described for other species of Polymastia. Occurring spicule types and sizes are different from known species of the area.     

Belonoperca pylei, a new species of seabass (Teleostei: Serranidae: Epinephelinae: Diploprionini) from the cook islands with comments on relationships among diploprionins

Belonoperca pylei is described from five specimens collected at depths of 68–122m from Rarotonga, Cook Islands. It differs from all other known diploprionin serranids in having IX, 10 dorsal-fin rays, III, 7 anal-fin rays, and a color pattern composed primarily of yellow and organge pigments. Cladistic analysis of epinepheline morphology supports monophyly of the diploprionin generaBelonoperca andDiploprion and suggests thatBelonoperca is the sister group ofDiploprion plus the monotypicAulacocephalus.     

The end of an 80-million year experiment: a review of evidence describing the impact of introduced rodents on New Zealand’s ‘mammal-free’ invertebrate fauna

Since separating from its super-continental origin 80 million years ago, New Zealand has effectively been isolated from the impacts of terrestrial mammals. The arrival of Polynesians in 13th C heralded the end of this era, with the introduction of kiore, (Rattus exulans, or Pacific rat), which had far-reaching effects on plant regeneration, survival of small ground vertebrates, larger invertebrates, and seabird breeding colonies. This paper reviews the evidence available from raptor nest sites and Quaternary beetle fossils to summarise extinctions thought to be caused by kiore in New Zealand. It also utilises invertebrate comparisons between islands with and without rats, or where rats have been eradicated, in order to document the impacts of rats (R. exulans, R. norvegicus) on invertebrate abundance, body mass, and the behavioural responses of some large New Zealand insects to the presence of rats. The role of a ‘mammal-free’ evolutionary history is discussed.     

Rapid community change at a tropical upwelling site in the Galápagos Marine Reserve

The high biodiversity of tropical marine communities has attractedconsiderable interest, yet we still lack a clear understanding of the tempo ofdiversity change in these systems []. Knowledge of the conditions associated with fast or slow community assembly inthe tropics would enhance our ability to predict recovery from natural andanthropogenic disturbance and to conserve biodiversity. Here we report anunusually rapid doubling of species richness within a year in a tropical,subtidal sessile invertebrate community in a protected (non-extractive) zone ofthe Galápagos Marine Reserve (GMR). Diversity changes in the rock wallcommunity were accompanied by large increases in the percent cover, densityand/or biomass of sponges, barnacles, ascidians, and an ahermatypic coral,Tubastrea coccinea, over the 1-year studyperiod (1999–2000). Barnacle (Megabalanuspeninsularis) and ascidian (Didemnum cineraceum)biomasses increased by an order of magnitude from 1999 to 2000. The greaterabundance of sessile invertebrate prey was accompanied by significant increasesin the abundance of barnacle and Tubastrea predators(Hexaplex princeps, Asperiscalabilleeana). An estimated 37% of barnacle tissue biomass productionwas consumed in 1 year. Temperature monitoring during the studyperiod showed that this site is characterized by strong upwelling, where rapid,3.0–9.0 °C decreases in temperature occurred at harmonicsof the semi-diurnal tidal periodicity during warm (January–February), butnot during cool months (June–July). Short-term acoustic current metermeasurements revealed strong, highly variable upwelling at the study site, withevents ranging from 2–111 min in duration and maximumupwelling velocities of 32.3 cm s^–1. Thesefindings suggest that the turnover of diversity and biomass may be unusuallyrapid at tropical upwelling sites, especially where invertebrate predators areprotected from harvesting. Consequently, upwelling sites may warrant specialconsideration in the planning of marine reserves to ensure the conservation ofbiodiversity.