The remote and poorly studied Gambier Islands, French Polynesia, has surprised scientists with a new coral species, Echinophyllia tarae, the occurrence of which is yet not credited to any other place. Echinophyllia tarae dwells in protected reef habitats and was found between 5 and 20 meters depth. It is a zooxanthellate species which usually grows on dead coral fragments, which are also covered by crustose coralline algae and fleshy macroalgae.
The species is found to grow on well illuminated surfaces but also known to encrust shaded underhangs and contributes to a great extent in the formation of coral reefs in the Gambier. It is mainly characterized by large polyps and bright often mottled colorations and it is very plastic in morphology like most hard corals, according to a Pensoft statement.
Patterns of partial death and recovery of the species were often observed and could be due to war with other benthic invertebrates like the soft-bodied corallimorpharians or zoanthids which can co-occur with this species. The discovery of this species is credited a muddy area where the pattern was commonly seen.
The new species has morphological affinities with both E. echinata and with Echinomorpha nishihirai, from which it can be discriminated on the basis of the diameter and the protrusion of the largest corallite, the thickness of the septa, and the development of the size of the crown of paliform lobes.
Stony corals are currently under threat and most of the species are getting extinct by the effects of global warming, ocean acidification and anthropogenic changes of reef structures. Although corals symbolize a comparatively well studied group of fascinating marine invertebrates, much has still to be understood of their biology, evolution, diversity, and biogeography. The discovery of this new species in French Polynesia is evidence that our knowledge of hard coral diversity is still deficient and that the exploration efforts of recent scientific expeditions like Tara Oceans can lead to new insights in a secluded and previously poorly studied locations.
This newly discovered 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 characteristically featuring pointed skeletal structures. In the same language, Tara is also the name of a sea goddess. The new species has given a new hope to the scientists to lead their exploration towards the poorly studied areas that could have surprises in store for them just like the Gambier Islands.
The original source of this study is the Zookeys journal.