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Many corals depend upon the highly specialised and intricate relationship they form with Symbiodiniaceae algal symbionts. Porites lutea is a massive reef-building coral found throughout Southeast Asia that hosts these endosymbionts obligately. Yet despite the prevalence and importance of P. lutea as one of the most dominant corals here, its associated Symbiodiniaceae communities have not been precisely characterised. In this study, we used high-throughput DNA amplicon sequencing of the nuclear internal transcribed spacer 2 (ITS2) to characterise the diversity, community structure and biogeographic distribution of Symbiodiniaceae in P. lutea throughout Singapore and Peninsular Malaysia. Consistent with previous studies, we found that Cladocopium was the most dominant genus among all samples, and Cladocopium C15 was the most dominant type (or subclade) with 100% occurrence in all samples from every study site. Results also revealed numerous Symbiodiniaceae types associated with P. lutea that were previously undetected in Southeast Asia. Endosymbiont diversity and community variation are driven by a combination of site-specific mean monthly cloud cover and variance in monthly sea surface temperature. This study contributes baseline data toward understanding differences in Symbiodiniaceae assemblages hosted by P. lutea, shedding light on how they might be indicative of particular environmental conditions and coral responses.

Bacterial diseases affecting corals pose an enormous threat to the health of coral reefs. The relationship between certain bacterial species and coral diseases remain largely unknown. Pigment abnormalities are common in Porites lutea. Here we used Illumina 16S rRNA gene sequencing to analyze the bacterial communities associated with healthy P. lutea and P. lutea with pigment abnormalities. We observed an increase of alpha diversity of the bacterial community of P. lutea with pigment abnormalities, relative to healthy corals. We then identified changes in the abundance of individual operational taxonomic units (OTUs) between pigmented and healthy corals. We were able to identify eight OTUs associated with pigment abnormalities, which are possibly the causative agents of pigment abnormalities.

Geochemical ratios in coral reef skeletons could be used as proxies to reconstruct past climatological and environmental records in data-poor regions. Using a 103-year data set (1902 to 2005), the annual variations in Ba/Ca and Mn/Ca ratios of Porites lutea skeletons at an eastern offshore area of Hainan Island (19°12´28.4´´N, 110°37´38.8´´E) were analyzed using inductively coupled plasma-optic emission spectrometry (ICP-OES). The analysis results showed that Ba/Ca ratios varied from a minimum of 3.120 μmol mol−1 in 1903 to a maximum of 10.064 μmol mol−1 in 1944, with an average of 5.256 μmol mol−1. Mn/Ca ratios varied from 0.206 to 5.708 μmol mol−1 with an annual average of 1.234 μmol mol−1, with peak values in 2001, 1964 and 1932, that correlated with strong rainfall events caused by typhoons. Variation in Ba/Ca and Mn/Ca ratios were compared with available river discharge and precipitation records, providing insight into past climatological events. Human activities and their indirect effects could impact the strength of the relationship between Ba/Ca and Mn/Ca ratios and observed precipitation and terrestrial input in the future.

Total genomic DNA of eight colonies for each of the two species, Acropora muricata and Porites lutea, sampled on the west coast of Reunion Island, was isolated using DNeasy Blood & Tissue kit (Qiagen™) following the manufacturer’s instructions and sent to GenoScreen, Lille, France (www.genoscreen.fr).

The reef coral Goniastrea aspera is regarded as one of the most environmentally tolerant species on Indo-Pacific reefs. Its demise, following a severe bleaching event in the Andaman Sea in the north-eastern Indian Ocean in 2010, was surprising in view of the rapid recovery of co-existing species such as Porites lutea. Demographic studies of G. aspera at this site showed the population was mainly composed of large individuals, which recruited in the early 1990s. These results, and size-specific mortality observed in G. aspera, post-bleaching, suggest that factors, related to size and age, may have contributed to the coral’s marked decline.

Coral reefs are threatened throughout the world. A major factor contributing to their decline is outbreaks and propagation of coral diseases. Due to the complexity of coral-associated microbe communities, little is understood in terms of disease agents, hosts and vectors. It is known that compromised health in corals is correlated with shifts in bacterial assemblages colonizing coral mucus and tissue. However, general disease patterns remain, to a large extent, ambiguous as comparative studies over species, regions, or diseases are scarce. Here, we compare bacterial assemblages of samples from healthy (HH) colonies and such displaying signs of White Plague Disease (WPD) of two different coral species (Pavona duerdeni and Porites lutea) from the same reef in Koh Tao, Thailand, using 16S rRNA gene microarrays. In line with other studies, we found an increase of bacterial diversity in diseased (DD) corals, and a higher abundance of taxa from the families that include known coral pathogens (Alteromonadaceae, Rhodobacteraceae, Vibrionaceae). In our comparative framework analysis, we found differences in microbial assemblages between coral species and coral health states. Notably, patterns of bacterial community structures from HH and DD corals were maintained over species boundaries. Moreover, microbes that differentiated the two coral species did not overlap with microbes that were indicative of HH and DD corals. This suggests that while corals harbor distinct species-specific microbial assemblages, disease-specific bacterial abundance patterns exist that are maintained over coral species boundaries. published

Nha Trang Bay (NTB) is located on the Central Vietnam coast, western South China Sea. Recent coastal development of Nha Trang City has raised public concern over an increasing level of pollution within the bay and degradation of nearby coral reefs. In this study, multiple proxies (e.g., trace metals, rare earth elements (REEs), and Y/Ho) recorded in a massive Porites lutea coral colony were used to reconstruct changes in seawater conditions in the NTB from 1995 to 2009. A 14-year record of REEs and other trace metals revealed that the concentrations of terrestrial trace metals have increased dramatically in response to an increase in coastal development projects such as road, port, and resort constructions, port and river dredging, and dumping activities since 2000. The effects of such developmental processes are also evident in changes in REE patterns and Y/Ho ratios through time, suggesting that both parameters are critical proxies for marine pollution.

Porites lutea in the Andaman Sea 17 and Diploastrea heliopora in the central Red Sea 2 , is negatively correlated with regional SST. However, these studies also show that the calcification response of corals to ocean warming is highly variable, both taxonomically and geographically. It is this variability in corals’ response to warming that has compelled investigations of the ability of corals to acclimatize and/or adapt to recent and predicted future ocean warming 3 , and whether their unique acclimatization and/or adaptive capacities can be used to improve coral reef management in the face of rapid global climate change 18 .

Most coral species off Australia’s west coast spawn in the austral autumn (March–April), with a few species also spawning in the southern spring or early summer (November–December). This is the reverse timing to spawning recorded off Australia’s east coast. Porites lutea, a gonochoric broadcast spawner that is common on Australia’s west coast, is shown here to spawn in the months of November or December, as it does on Australia’s east coast. Spawning occurred between 2 and 5 nights after full moon, with the majority of spawning activity on night 3. Gametes developed over three to four months with rapid development in the last two weeks before spawning. Zooxanthellae were typically observed in mature oocytes, only a week before spawning so their presence may provide a useful indicator of imminent spawning.

The metabolic plasticity of the two mounding coral species Porites lutea (Milne-Edwards and Haime, 1860) and Diploastrea heliopora (Lamarck, 1816) was investigated in the Similan Islands (Thailand), an offshore Andaman Sea island group subjected to large amplitude internal waves (LAIW). Nutrient concentrations were highly correlated with LAIW intensity and contributed to 3- and 10-fold higher symbiont densities in P. lutea and D. heliopora, respectively, along with elevated pigment concentrations, protein content, host tissue, and symbiont biomass. The comparison of LAIW-exposed and LAIW-sheltered island faces, and LAIW-intense and LAIW-weak years suggests a species-specific metabolic plasticity to LAIW, where D. heliopora benefits more from increased nutrient and organic matter availability than P. lutea. The ubiquitous LAIW in Southeast Asia and beyond may provide so far unexplored clues to coral acclimatization to disturbances on various scales, and hence, a potential key to coral resilience to climate change.

A new species of xarifiid copepod, Orstomella yaliuensis n. sp., is described. It was found living in the polyps of a scleractinian coral, Porites lutea Milne Edwards & Haime, collected off Yaliu in the northern part of Taiwan. The new species can be distinguished from its two congeners, O. faviae Humes & Ho, 1968 and O. lobophylliae Humes & Ho, 1968, by the presence of five (rather than six) segments on the antennule, a spine only (rather than a seta and a spine) at the tip of the antenna, a uniramous leg 2, and a relatively long (rather than short) spine at the tip of the caudal ramus.

High resolution Mg/Ca ratios in the skeleton of aPorites lutea from the coastal area in the North of the South China Sea were precisely analyzed by ICP-MS. Compared with the instrument measured SST records, the Mg/Ca ratios strongly correlate with the SSTs, even in time of 1982/83 El Nino. Therefore, a coral Mg/Ca thermometer for the North of the South China Sea was established. Based on ICP-MS technique it can report sea surface temperatures to an accuracy of ±0.5°C.

[Extract] One of the largest and oldest single hermatypic coral colonies known is a massive Porites coral located on the southwest corner of Ta'u island (14°15S, 169°30W) in the Manu'a group of American Samoa. The coral is believed to be Porites lutea based on colony and corallite morphology; however, Porites taxonomy is notoriously difficult and recent genetic work has revealed surprising levels of cryptic diversity (Forsman et al.2009). Small (1 cm) cores were collected for genetic and microscopic work, and to determine skeletal density. DNA sequence for mitochondrial (COI, COIII) and nuclear (ITS region) markers were deposited in GenBank (accession numbers ITS-FJ416523-6, mt COI-FJ423967, and mt control FJ427369), and skeletal voucher specimens have been deposited at the Bishop Museum (SC4164).

Alternate dense and less-dense skeletal bands in massive corals have been used for many years to record the history of growth in species such as Porites lutea and Montastrea annularis, based on the assumption that one dense band and one less-dense band is equivalent to a year's growth. This report demonstrates that specimens of Porites lutea Edwards and Haime (collected from the same neighbourhood in Phuket, Thailand, from November 1983 through November 1984) produce skeletal bands asynchronously and that one year's growth in corals from certain sites may regularly consist of four bands of varying density. The annual banding pattern observed at all sites includes the deposition of a dense band in response to high sedimentation loads and, probably, reduced light levels.