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Molecular evidence shows low species diversity of coral-associated hydroids in Acropora corals.

ABSTRACT: A novel symbiosis between scleractinians and hydroids (Zanclea spp.) was recently discovered using taxonomic approaches for hydroid species identification. In this study, we address the question whether this is a species-specific symbiosis or a cosmopolitan association between Zanclea and its coral hosts. Three molecular markers, including mitochondrial 16S and nuclear 28S ribosomal genes, and internal transcribed spacer (ITS), were utilized to examine the existence of Zanclea species from 14 Acropora species and 4 other Acroporidae genera including 142 coral samples collected from reefs in Kenting and the Penghu Islands, Taiwan, Togian Island, Indonesia, and Osprey Reef and Orpheus Island on the Great Barrier Reef, Australia. Molecular phylogenetic analyses of the 16S and 28S genes showed that Acropora-associated Zanclea was monophyletic, but the genus Zanclea was not. Analysis of the ITS, and 16S and 28S genes showed either identical or extremely low genetic diversity (with mean pairwise distances of 0.009 and 0.006 base substitutions per site for the 16S and 28S genes, respectively) among Zanclea spp. collected from diverse Acropora hosts in different geographic locations, suggesting that a cosmopolitan and probably genus-specific association occurs between Zanclea hydroids and their coral hosts.

SUBMITTER: Fontana S

PROVIDER: S-EPMC3510231 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Molecular evidence shows low species diversity of coral-associated hydroids in Acropora corals.

Fontana Silvia S Keshavmurthy Shashank S Hsieh Hernyi Justin HJ Denis Vianney V Kuo Chao-Yang CY Hsu Chia-Ming CM Leung Julia K L JK Tsai Wan-Sen WS Wallace Carden C CC Chen Chaolun Allen CA

PloS one 20121129 11

A novel symbiosis between scleractinians and hydroids (Zanclea spp.) was recently discovered using taxonomic approaches for hydroid species identification. In this study, we address the question whether this is a species-specific symbiosis or a cosmopolitan association between Zanclea and its coral hosts. Three molecular markers, including mitochondrial 16S and nuclear 28S ribosomal genes, and internal transcribed spacer (ITS), were utilized to examine the existence of Zanclea species from 14 Ac ...[more]

PMID: 23209655

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Molecular evidence shows low species diversity of coral-associated hydroids in Acropora corals.

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Molecular evidence shows low species diversity of coral-associated hydroids in Acropora corals.

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