Just when we thought 2013 was going to be mediocre for new coral species descriptions, along comes Ctenactis triangularis to show us there’s still some surprises in stony corals this year. Described from three specimens in the Andaman Sea, Ctenactis triangularis stands out from other members of this genus, literally, with an extra lobe that projects the colony outline into a triangle.
We know what you’re thinking,there’s plenty of examples of triangular and cross-shaped Herpolitha tongue and Polyphyllia slipper corals and they aren’t elevated to species level. But apparently, the researchers Mondal and Ranghunathal found a number of other morphological differences to distinguish C. triangularis from other species in the genus Ctenactis. In their own words:
“Morphological plasticity can be observed among these species, but this is not morphological differentiation of previously described species as all the characters of key components such as septa, costae, mouth and their arrangement is totally different from previously recorded species. The analytical result of all the characters of the described species is definitely a new description. “
We were able to find other examples of triangular shaped Ctenactis corals from places as far flung from the Andaman Islands as the northern Red Sea and Japan. The Red Sea triangular Ctenactis was photographed in Eilat Aqaba in the Gulf of Aqaba while the Japanese specimen is a skeleton in a collection with an undivulged location, so there’s no telling where it was discovered.
Without close examination it’s not exactly possible to tell whether these other triangular Ctenactis specimens are morphological mutants of pre-existing Ctenactis species or if they represent a range extension for C. triangularis. The newest species in the Fungiidae family is described in the August 2013 volume of the Journal of Threatened Taxa.