The family Acroporidae (Scleractinia) formerly contained four genera such as Acropora, Anacropora, Astreopora, and Montipora (for examples, Veron and Wallace 1984; Nishihira and Veron 1995; Veron 2000). Recently, Wallace et al. (2007) has elevated the subgenus Isopora, which was one of two subgenera in the genus Acropora, to genus, based on the morphological, ecological and molecular data. Then number of genera in the Acroporidae becomes five. Nevertheless, in Japan, this fact is not generally known and the genus name Acropora is still applied to the species, which should belong to the new genus Isopora. In this paper, to make public the name of the genus Isopora, and to propose the Japanese name of this genus, we summarize the morphological and ecological characters of this genus. The contents of this paper are mainly based on Wallace et al. (2007). In addition, we show morphological and ecological data from samples of Isopora that were collected in Japan. On the basis of the International Code of Zoological Nomenclature (Art. 69.2.2), we note that type species of Isopora is Madrepora labrosa Dana, 1846, not Astrea palifera Lamarck, 1816.

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A typhoon is one of environmental factors to affect coral reef ecosystems. Winds and ocean wave (wind wave and swell) induced by typhoons generates various effects of mechanical destruction (dislodgement, overturned, breakage), sedimentation, change in reef topography, and sea-water cooling. Sediment and nutrients discharges induced by heavy rainfall have impacts on benthic organisms. Some climate models project that typhoons and the corresponding maximum wind velocity and precipitation will become more intense (i.e., super typhoon) with time. Future reef ecosystems are thus expected to be more affected by the super typhoons. In this paper, we describe the effects of typhoons on coral reef ecosystems and summarize the aim of the research. In addition, we review the latest studies of effects of super typhoons on coral reef ecosystems and give guidance to further studies.

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Skeletal growth parameters (extension rate, density and calcification rate) were determined for annual growth bands in skeletal slabs and tips of the zoothanthellate scleractinian (hermatypic) coral Dipsastraea speciosa (Dana, 1846) [= Favia speciosa (Dana, 1846)] at Iriomote Island in the southwestern part of the Ryukyus (24°25′N, 123°47′E) and at Fukue, Wakamatsu, Iki and Tsushima islands in the northwestern part of Kyushu (32°39′N – 34°24′N, 128°39′E – 129°40′E), Japan. Relationships among these three parameters along a latitudinal gradient in annual mean sea surface temperatures (SSTs) were also examined. Annual mean density and calcification rate in D. speciosa of Iriomote Island located in a subtropical region (Iriomote Is.) were higher than those of the other islands in temperate regions, although there was no significant difference in the extension rates between the two regions. These results agreed well with those of Porites astreoides Lamarck, 1816 in the Atrantic rather than those of the Atlantic Orbicella (= Montastraea) and the Pacifc Porites species. Both Dipsastraea speciosa and Porites astreoides are geographically widespread species, and they have lower extension and calcification rates than other neighboring genera/species. Of the three growth parameters of D. speciosa, the calcification rate showed the highest significant correlation with the annual mean SSTs. It suggests that while D. speciosa distributed in the Japanese islands could keep their calcification rates stable for each site, they change their extension rates and densities in response to the latitudinal gradient in annual mean SSTs.

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Large benthic foraminifer (LBF) is a collective term for benthic foraminifers with a relatively large shell size, living in coral reef and associated environments. Current knowledge of taxonomy, phylogeny, physiology and ecology of LBFs is reviewed. Extant LBFs belong to at least 24 genera, six families, and two orders. Fossil records of LBFs demonstrated that all modern genera originated before the Pleistocene (Quaternary).
LBFs have endosymbiotic relationships with different types of microalgae such as dinoflagellates, chrolophytes, pennete diatoms, and rhodophytes. Algal symbiosis is advantageous in nutrient-deficient, clear, well-lit environments. The degree of dependence to algal symbiosis varies with taxa; miliolids are less dependent to algal symbiosis than rotaliids. Most morphological characters possessed in each taxon are considered to be the adaptation to algal symbiosis. Algal symbiosis may be a key driver to the morphological evolution of LBFs.
LBFs grow by adding a new chamber along with protoplasmic growths. The processes of chamber formation and calcification mechanisms differ between rotaliids and miliolids. Life cycles of LBFs are characterized by the alternation of sexual and asexual generations called dimorphism or trimorphism. Gamonts reproduce sexually by releasing free-swimming gametes in the surrounding water. Agamont or schizont reproduces asexually by multiple fission either inside the shell (internal schizogony) or outside the shell (external schizogony).
The biogeographic distribution of LBFs is divided into four regions (West Pacific, Indian to central Pacific, West Indian to the Middle East, Caribbean and Atlantic). Depth distributions of algal symbiont-bearing LBFs are restricted to photic zones (down to 130m in depth) of tropical and subtropical seas. Different genera and species show different preferences along environmental gradients of water depth and reef flats. LBFs are epifauna living on surfaces of macroalgae, seagrass, coral rubble, and sediment.
Population densities and structures of LBFs vary with habitats and seasons; the population density in subtropical environments increases during spring and summer, and decreases during fall and winter. The longevity of LBFs generally ranges from a few months to 1.5 years. Survivorship curves of LBFs may be determined by the size of juveniles and the mode of asexual reproduction. Carbonate production rates of LBFs are generally from 10 to 10³g CaCO₃ m^-2 yr^-1.

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Chronological changes in heavy metal concentrations were investigated by chemical analysis of core sediments from Manko tidal land, downstream area of the Kokuba and Noha rivers in Naha city. It is located in a densely-populated area, and the soil has been contaminated with heavy metals from development upstream flowing into the tidal land. The sedimentation rate of cores measured using the ²¹⁰ Pb _ex method was estimated to be 1.1-1.9cmy^-1 (2.1-3.7gcm^-2y^-1), a relatively rapid rate. Depth profiles of the aluminum content in the sediment showed only a small variation, whereas the calcium content tended to increase. Lead also showed a tendency to increase through the 1980s, but has decreased ever since likely influenced by the popularization of unleaded gasoline. Other heavy metals such as Ni, Cu and Hg showed a low concentration downstream of the Noha river but showed a high concentration in the confluence area of the two rivers. This result suggests that these elements in the sediment likely originated from the Kokuba river.

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Monitoring the health of coral is imperative following the global coral-bleaching episode that occurred in 1998, and because climate change is ongoing. However, the usual method employed to monitor coral is visual inspection, which is unable to determine some fine-detailed changes. It is known that symbiotic zooxanthellae supply coral with many nutrients and cause some changes in the reflection spectrum of the coral. Thus, we believe it is possible to monitor coral by monitoring zooxanthellae. By performing pixel operations on two pictures, taken in blue and near-infrared light, a “normalized difference vegetation index for coral” (hereafter referred to as NDCI) can be defined. Measuring photosynthetic activity by PAM, in the same area as measured by NDCI, shows high correlation between Fv/Fm and NDCI (Saito et al. 2008). We used this system to obtain estimates of the seasonal and diurnal variations of coral and converted them into numbers using the NDCI. The measurements of coral in this investigation were performed on the Ishigaki Island Shiraho reef during 2009-2010 and 2011-2012. It was found that seasonal variation of the NDCI value shows an inverse correlation with water temperature. Furthermore, the seasonal variation in the range of the NDCI value was found to depend on the species of coral. We conclude that coral exhibits change, both seasonally and diurnally, in response to low and high temperature, stress induced by light levels, and incursions of mud. Interestingly, we can also report that we observed strong and weak bleaching and deviations of the NDCI value following the passage of a typhoon.

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In 2012, Dr. Ann F. Budd and colleagues revised the taxonomy of the families Mussidae and Faviidae, based on the published molecular phylogenetic data and the detailed skeletal morphological analyses. In this revision, Atlantic Mussidae and Faviidae were treated as the separate families from the Indo-Pacific ones. According to this revision, Indo-Pacific Mussidae and Faviidae, and also the genera Favia and Montastraea were revised taxonomically and these names were changed. These changes may confuse some coral scientists on various situations such as writing papers. Therefore, in this paper, I summarized the revision of the families Mussidae and Faviidae, explaining the reason why they were revised.

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