Little is known about effects of large storm systems on mesophotic reefs. This study reports on how Typhoon 17 (Jelawat) affected Ryugu Reef on Okinawa-jima, Japan in September 2012. Benthic communities were surveyed before and after the typhoon using line intercept transect method. Comparison of the benthic assemblages showed highly significant differences in coral coverage at depths of 25–32 m before and after Typhoon 17. A large deep stand of Pachyseris foliosa was apparently less resistant to the storm than the shallower high diversity area of this reef. Contradictory to common perception, this research shows that large foliose corals at deeper depths are just as susceptible to typhoon damage as shallower branching corals. However, descriptive functional group analyses resulted in only minor changes after the disturbance, suggesting the high likelihood of recovery and the high resilience capacity of this mesophotic reef.

Oyster veligers Ostrea edulis fed on Pavlova lutheri at 21 °C gave a functional feeding response with micro-algal concentration of the hyperbolic type, Ingestion, /, being represented by the formulaF o being nitration rate in units of volume/time, C concentration of suspension and T having dimensions of time. This formula has the advantage not only of being consistent logically at high and low concentration, but also that its two constants have a simple meaning, F o is the rate of nitration asC->o and x/r is the rate as C -> 00.Maximum filtration rates are achieved only at low micro-algal concentrations, and tend to a maximum ingestion rate at high concentrations, as almost universally observed by other workers. In O. edulis the equation / = 151 C/(i +00062 C), where C is cells /il' 1 , represented feeding over a range of C = 20-260 /A' 1 , and / is in cells h" 1 .The hyperbolic relation is identical with the Holling's disc equation for predator-prey encounter, but it is suggested that this may be just a pragmatic similarity or true for quite different reasons, since pelagic larvae do not stop filtering (equivalent to the predator's searching activity) while handling. For example, it is demonstrated that viscous properties of a mucus concentrate of about 10 5 times that of the ambient suspension derived from ingested algae would account for the same relation. Calculations from feeding/concentration curves of other workers lead to similar hyperbolic relationships, though the behaviour of different batches of larvae may result in considerable variation in F g , the filtration rate extrapolated to zero concentration.The temperature coefficient of feeding reaches a maximum at ca. 20 °C and has a Q l0 of 3-4. It will therefore compensate for the increased metabolic loss at higher temperature.Veliger larvae appear not to discriminate between algal species or algal sizes when fed on mixtures of Nannochloris (5.2 /im 3 ), Isochrysis (23 /an 3 ) and Tetraselmis (230 /tm 3 ). This is consistent with the theory of viscous interference with rate of uptake at high cell density, but further work on large and small microalgae would be desirable to test the theory further.The functional response is used to calculate energy budgets at different cell suspension densities. Our results together with those of Jespersen & Olsen and of Sprung indicate that whereas larvae of Mytilus edulis can grow at cell suspension levels described for average sea and estuarine conditions, oyster larvae require higher food levels to maintain adequate growth, indeed levels more characteristic of hatchery practice. Two possibilities are put forward to account for survival under natural conditions; first, supplementation by very small nutrient particles such as smaller flagellates, bacteria and detritus which normally escape being recorded; secondly, direct uptake of dissolved nutrients. * Present address: Pollution Research Unit, The University, Manchester M13 9PL.

Okinawa, Japan is known for its high marine biodiversity, yet little work has been performed on examining impacts of numerous large-scale coastal development projects on its marine ecosystems. Here, we examine apparent impacts of the construction of the Kaichu-Doro causeway, which was built over 40 years ago. The causeway is a 4.75 km long embankment that divides a large tidal flat and has only two points of water exchange along its entire length. We employed quadrats, transects, sampling, visual surveys, and microbial community analyses combined with environmental, water quality data, and 1m cores, at five stations of two paired sites each (one on each side of Kaichu-Doro) to investigate how the environment and biota have changed since the Kaichu-Doro was built. Results indicate reduction in water flow, and site S1 was particularly heavily impacted by poor water quality, with low diversity and disturbed biotic communities.

The taxonomy of the amphipod family Leucothoidae has been reviewed and changes are proposed. Currently, there are 139 described species of leucothoids in two clades. The anamixid clade contains 39 species and the leucothoid clade contains 100 species. For the first time in a single work, diagnoses, distributions, and available host data are presented for all extant species of the Leucothoidae. The genus Leucothoella has been suppressed based on morphological similarities to the genus Leucothoe. The genera Anamixis and Paranamixis need revision, as the major defining character of Paranamixis (absence of gnathopod 1) is likely developmental. However, due to lack of available data, the genera currently remain separate. Identification keys are provided for all but five poorly described species in the family.