Symbiodinium diversity in mesophotic coral communities on the Great Barrier Reef: a first assessment

Marine Ecology Progress Series

Pim Bongaerts¹  Thomas C. L. Bridge¹  Eugenia M. Sampayo¹  Francisca Vermeulen¹  Ove Hoegh-Guldberg¹  Norbert Englebert¹  Tyrone Ridgway¹  Jody M. Webster¹ 

关键词: Symbiodinium;    Mesophotic;    Deep reefs;    Coral;    ITS2;    DGGE;    Great Barrier Reef;   

DOI  :  10.3354/meps09315

学科分类：海洋学与技术

来源: Inter-Research

【 摘 要 】

ABSTRACT: Despite a growing interest in mesophotic coral ecosystems (MCEs), information on the photosynthetic endosymbionts (genus Symbiodinium) associated with scleractinian corals inhabiting deep reef ecosystems is sparse. Here, the deep-water Symbiodinium diversity is assessed from 10 different coral genera at a depth range of 45 to 70 m on the Great Barrier Reef (GBR), Australia. Symbiodinium identity was established using denaturing gradient gel electrophoresis (DGGE) fingerprinting of the internal transcribed spacer region 2 (ITS2) of the ribosomal DNA. Except for the novel Symbiodinium type C131 (found in Porites), all Symbiodinium types have previously been identified in shallow reef corals across the Pacific. Specimens of Seriatopora, Montipora, and Porites harboured similar symbionts as reported in shallow water (e.g. C3n, C3n-hh, C15, and C17), thus adhering to patterns of host-specificity across a wide depth range. However, several other Symbiodinium types were found to transcend previously established patterns of host-specificity at mesophotic depths. For example, ‘host-specialist’ types C3i and C3k (previously only reported in Acropora spp.) were found here to associate with a range of different genera (Leptoseris, Pachyseris, Fungia, and Echinophyllia). Although limited in sample size, this preliminary survey indicates that mesophotic habitats on the GBR may not represent an isolated community in terms of Symbiodinium diversity, which has significant relevance to their potential to act as refugia. Moreover, the present study identifies the need to examine symbiont diversity across broad environmental ranges (including MCEs) in order to gain an accurate understanding of symbiosis specificity and distribution range of specific coral-Symbiodinium associations.

【 授权许可】

Unknown