Publications:

Wagner et al. 2011


scientific article | Proc Biol Sci | open access Open access

Azooxanthellate? Most Hawaiian black corals contain Symbiodinium

Wagner D, Pochon X, Irwin L, Toonen RJ, Gates RD

Adobe pdf
Www
Gscholar
Abstract

The ecological success of shallow-water reef-building corals (Hexacorallia: Scleractinia) is framed by their intimate endosymbiosis with photosynthetic dinoflagellates in the genus Symbiodinium (zooxanthellae). In contrast, the closely related black corals (Hexacorallia: Anthipatharia) are described as azooxanthellate (lacking Symbiodinium), a trait thought to reflect their preference for low-light environments that do not support photosynthesis. We examined 14 antipatharian species collected between 10 and 396 m from Hawai'i and Johnston Atoll for the presence of Symbiodinium using molecular typing and histology. Symbiodinium internal transcribed spacer-2 (ITS-2) region sequences were retrieved from 43 per cent of the antipatharian samples and 71 per cent of the examined species, and across the entire depth range. The ITS-2 sequences were identical or very similar to those commonly found in shallow-water scleractinian corals throughout the Pacific. Histological analyses revealed low densities of Symbiodinium cells inside antipatharian gastrodermal tissues (0-92 cells mm(-3)), suggesting that the Symbiodinium are endosymbiotic. These findings confirm that the capacity to engage in endosymbiosis with Symbiodinium is evolutionarily conserved across the cnidarian subclass Hexacorallia, and that antipatharians associate with Symbiodinium types found in shallow-water scleractinians. This study represents the deepest record for Symbiodinium to date, and suggests that some members of this dinoflagellate genus have extremely diverse habitat preferences and broad environmental ranges.

10.1098   rspb.2010.1681
Keywords
Meta-data
Depth range
10- 396 m

Mesophotic “mentions”
7 x (total of 3058 words)

Fields
Molecular ecology
Physiology
Evolution

Focusgroups
Antipatharia (Black Corals)
Symbiodinium (zooxanthellae)

Locations
USA - Hawaii
USA - Johnston Atoll

Platforms
Diving - Regular Open-Circuit
Manned Submersible

Author profiles
Xavier Pochon ( 4 pubs)
Rob Toonen ( 12 pubs)
Daniel Wagner ( 23 pubs)