Tara discovers a new coral reef species

© Corail

A new shallow water coral species, Echinophyllia tarae sp. n., is described from the Gambier Islands, French Polynesia.

The remote and poorly known Gambier islands were explored by the Tara Oceans international research expedition in 2011. Scleractinia, also called stony corals, are ancient and structurally simple marine animals which have the ability to form hard skeletons and are involved in the build up of coral reefs. This new coral is common in the lagoon reefs of the Gambier, and was observed in muddy environments where several colonies showed partial mortality and re-growth. The paper devoted to the new species was published in the open access journal ZooKeys.

The new species Echinophyllia tarae is described from the remote and poorly studied Gambier Islands, French Polynesia. Although the new species is common in the lagoon of Gambier Islands, its occurrence elsewhere is unknown. Echinophyllia tarae lives in protected reef habitats and was observed between 5 and 20 m depth. It is a zooxanthellate species which commonly grows on dead coral fragments, which are also covered by crustose coralline algae and fleshy macroalgae. This species can grow on well illuminated surfaces but also encrusts shaded underhangs and contributes to the formation of coral reefs in the Gambier. It is characterized by large polyps and bright often mottled colourations and it is very plastic in morphology like most hard corals. Patterns of partial death and recovery of the species were often observed and could be due to competition with other benthic invertebrates like the soft-bodied corallimorpharians or zoanthids which can co-occur with this species.

Stony corals are currently under threat by the effects of global warming, ocean acidification and anthropogenic changes of reef structures. Although corals represent a relatively well studied group of charismatic marine invertebrates, much has still to be understood of their biology, evolution, diversity, and biogeography. The discovery of this new species in French Polynesia confirms that our knowledge of hard coral diversity is still incomplete and that the exploration efforts of recent scientific expeditions like Tara Oceans can lead to new insights in a remote and previously poorly studied locations.

This species is named after the Tara vessel which allowed the exploration of coral reefs in Gambier. Moreover, the name “tara” in the Polynesian language may refer to a spiny, pointed object, which applies well to the new species typically featuring pointed skeletal structures. In the same language, Tara is also the name of a sea goddess.


From 2009 to 2012, Tara traveled the world’s oceans exploring marine micro-organisms.
Though the Tara Oceans expedition was primarily devoted to the study of plankton, a hundred coral sites were sampled, allowing scientists to collect nearly 200 samples in large reefs all over the world, from Djibouti to St. Brandon and Mayotte. It turns out that a dozen unknown species were discovered !

2013: New expedition to the Far North, Tara Oceans Polar Circle 

From May to November, Tara circumnavigates the Arctic Ocean by the Northeast and Northwest Passages. Most of the scientists and institutes involved in the previous Tara Oceans expedition also participate in this project to study the polar marine ecosystem and complement the work done since 2009. New research programs specific to this region are added concerning plastic particles and other pollutants. The expedition has also a political purpose by putting on center stage a region at the heart of the world’s climate system.

Yann Chavance

Reference

Benzoni F. (2013) Echinophyllia tarae sp. n. (Cnidaria, Anthozoa, Scleractinia), a new reef coral species from the Gambier Islands, French Polynesia

To read the publication in ZooKeys: click here