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As evolutionary relationships among some coral species still remain unclear, studies on unstudied area such as the Persian Gulf (PG), as part of the western Indo-Pacific, may reveal a better understanding of phylogenetic positions and relationships of corals. In the present study, the phylogenetic relationships of eight common coral species (Favites pentagona, Platygyra daedalea, Cyphastrea microphthalma, Siderastrea savignyana, Pavona decussata, Pavona cactus, Goniopora columna, and Goniopora djiboutiensis) collected from two Iranian Islands were compared with the congeneric sequences from the Indo-Pacific (IP) using rDNA region. The result shows that some coral species which were hitherto considered as representatives of widespread species from IP are related to distinct lineages. Further, it appears that morphological convergence between the taxa leads to an underestimation of the real coral species diversity in the PG. The current study is the first attempt to investigate the phylogenetic position of coral species from the PG in comparison to their counterparts from the IP. As conservation planning hinges on the identification of species, taxonomic revisions have to be undertaken in order to obtain a more reliable picture of coral species diversity in the PG.

Coral reefs are increasingly threatened by thermal bleaching and tropical storm events associated with rising sea surface temperatures. Deeper habitats offer some protection from these impacts and may safeguard reef-coral biodiversity, but their faunas are largely undescribed for the Indo-Pacific. Here, we show high species richness of scleractinian corals in mesophotic habitats (30-125 m) for the northern Great Barrier Reef region that greatly exceeds previous records for mesophotic habitats globally. Overall, 45% of shallow-reef species (less than or equal to 30 m), 78% of genera, and all families extended below 30 m depth, with 13% of species, 41% of genera, and 78% of families extending below 45 m. Maximum depth of occurrence showed a weak relationship to phylogeny, but a strong correlation with maximum latitudinal extent. Species recorded in the mesophotic had a significantly greater than expected probability of also occurring in shaded microhabitats and at higher latitudes, consistent with light as a common limiting factor. The findings suggest an important role for deeper habitats, particularly depths 30-45 m, in preserving evolutionary lineages of Indo-Pacific corals. Deeper reef areas are clearly more diverse than previously acknowledged and therefore deserve full consideration in our efforts to protect the world's coral reef biodiversity.

Recent phylogenetic analyses have demonstrated the limits of traditional coral taxonomy based solely on skeletal morphology. In this phylogenetic context, Faviidae and Mussidae are ecologically dominant families comprising one third of scleractinian reef coral genera, but their phylogenies remain partially unresolved. Many of their taxa are scattered throughout most of the clades of the Robust group, and major systematic incongruences exist. Numerous genera and species remain unstudied, and the entire biogeographic area of the Indian Ocean remains largely unsampled. In this study, we analyzed a portion of the mitochondrial cytochrome c oxidase subunit 1 gene and a portion of ribosomal DNA for 14 genera and 27 species of the Faviidae and Mussidae collected from the Indian Ocean and New Caledonia and this is the first analysis of five of these species. For some taxa, newly discovered evolutionary relationships were detected, such as the evolutionary distinctiveness of Acanthastrea maxima, the genetic overlap of Parasimplastrea omanensis and Blastomussa merleti, and the peculiar position of Favites peresi in clade XVII together with Echinopora and Montastraea salebrosa. Moreover, numerous cases of intraspecific divergences between Indian Ocean and Pacific Ocean populations were detected. The most striking cases involve the genera Favites and Favia, and in particular Favites complanata, F. halicora, Favia favus, F. pallida, F. matthaii, and F. rotumana, but divergence also is evident in Blastomussa merleti, Cyphastrea serailia, and Echinopora gemmacea. High morphological variability characterizes most of these taxa, thus traditional skeletal characteristics, such as corallite arrangement, seem to be evolutionary misleading and are plagued by convergence. Our results indicate that the systematics of the Faviidae and the Mussidae is far from being resolved and that the inclusion of conspecific populations of different geographical origin represents an unavoidable step when redescribing the taxonomy and systematics of scleractinian corals. More molecular phylogenies are needed to define the evolutionary lineages that could be corroborated by known and newly discovered micromorphological characters., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Coral reefs are increasingly threatened by thermal bleaching and tropical storm events associated with rising sea surface temperatures. Deeper habitats offer some protection from these impacts and may safeguard reef-coral biodiversity, but their faunas are largely undescribed for the Indo-Pacific. Here, we show high species richness of scleractinian corals in mesophotic habitats (30-125 m) for the northern Great Barrier Reef region that greatly exceeds previous records for mesophotic habitats globally. Overall, 45% of shallow-reef species (less than or equal to 30 m), 78% of genera, and all families extended below 30 m depth, with 13% of species, 41% of genera, and 78% of families extending below 45 m. Maximum depth of occurrence showed a weak relationship to phylogeny, but a strong correlation with maximum latitudinal extent. Species recorded in the mesophotic had a significantly greater than expected probability of also occurring in shaded microhabitats and at higher latitudes, consistent with light as a common limiting factor. The findings suggest an important role for deeper habitats, particularly depths 30-45 m, in preserving evolutionary lineages of Indo-Pacific corals. Deeper reef areas are clearly more diverse than previously acknowledged and therefore deserve full consideration in our efforts to protect the world's coral reef biodiversity. [ABSTRACT FROM AUTHOR]

The morphometric and molecular boundaries between twelve Psammocora (Cnidaria, Scleractinia) nominal species were addressed. The type specimens of Psammocora haimiana, P. togianensis, P. folium, P. digitata, Maeandroseris australiae, P. samoensis, P. superficialis, P. profundacella, P. nierstraszi, P. verrilli, and P. albopicta, were analysed together with specimens from museum collections, including those depicted in widely cited taxonomic descriptions, and material collected for this study in different parts of the Indo-Pacific. Morphometric analyses of the dimensions of skeletal structures allowed the identification of groups of specimens with similar morphologies. Congruency between these groups and current species whose synonymies and descriptions were found in recent taxonomic references was, hence, investigated and the species revised. Finally, the phylogenetic relationships of a representative subset of specimens were reconstructed based on rDNA and COI, thus allowing a direct link between morphologic and genetic information. Incongruence between type of morphology and literature descriptions was evidenced for some widely recognised species. Based on this integrated approach, five species were unambiguously identified. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, , 421-456. [ABSTRACT FROM AUTHOR]

The Indo-Pacific coral genus Psammocora Dana (1846) has never been formally revised, and its phylogeny has only been partially explored. Several synonymies have been proposed for the 11 nominal species which have highly plastic branching growth forms. In the present study, the definition of genetic and morphologic boundaries among three currently recognized branching morpho-species, Psammocora stellata, Psammocora contigua and Psammocora obtusangula, is addressed through a joint morphometric and molecular study using corallite and branch measurements, and a portion of the β-tubulin gene as a marker. The results show a morphological and partial phylogenetic distinction between P. stellata specimens and a complex composed of P. contigua and P. obtusangula, which is interpreted as a synonym species of P. contigua. Among the factors that could be responsible for the lack of reciprocal monophyly of the three species, hybridization is considered the most likely, due to the presence of interspecific recombinant sequences. Type material of nominal species of branching Psammocora is examined and classified based on genetically defined groups, and compared with synonym in the literature. Among the morphological characters used, corallite variables were best for discriminating between the two lineages and allow recognition of putative hybrid specimens. Psammocora stellata is reported for the first time in the western Indian Ocean (Mayotte), thus greatly extending its known distribution range. Finally, a hybrid swarm is identified in the Arabo-Persian Gulf, while no genetic structure is detected elsewhere in the Indo-Pacific region. [ABSTRACT FROM AUTHOR]

Until coral molecular phylogenies were published, the genus Plesiastrea was traditionally part of the family Faviidae and considered by several authors to be closely related to the genus Montastraea. However, genetic data has shown that Plesiastrea versipora, the genus type species, is evolutionarily distinct within the Robust clade of the Scleractinia and does not belong to the large clade grouping most representatives of the families Faviidae, including Montastraea, Mussidae, Merulinidae, Trachyphylliidae, and Pectiniidae. Instead, P. versipora is closely related to non reef-dwelling taxa currently ascribed to the Oculinidae (Cyathelia axillaris) and Caryophylliidae (Trochocyathus efateensis). However, no discussion on the morphologic features of P. versipora compared to other taxa has been published yet. Moreover, no information is available about the phylogenetic placement of Plesiastrea devantieri, the only other species in the genus. The phylogeny of both Plesiastrea species was addressed through molecular analyses (COI and rDNA) and morphological analysis. Morphological differences between the two species included number of septa, cycles of vertical structures in front of the septa and septal micromorphology. On the basis of these data and nuclear and mitochondrial markers, P. devantieri belongs to the Faviidae-Merulinidae-Pectiniidae-Trachyphylliidae clade (Clade XVII sensu Fukami et al., 2008) and is most closely related to Goniastrea aspera and G. palauensis. The type species of the genus Goniastrea, G. retiformis, however, is not closely related to either G. aspera and G. palauensis, or to P. devantieri. Taxonomic implications of these findings and morphologic affinities between the two species and closely related taxa are discussed [ABSTRACT FROM AUTHOR]