Primnoa ghostbusteri?

By Lance Morgan

The Finding Coral team found large red tree coral (Primnoa) at several sites. After our discovery of Primnoa at Juan Perez Sound, we found additional colonies at Portland Inlet and East Dixon Entrance.

Red tree coral form lush forests of habitat where we observed rockfish, shrimp and other invertebrates among the branches. Also lurking in the forest were sea stars (Hippasteria) and sea slugs (the innocently named, orange-peel nudibranch) that dine on Primnoa.  

To counter these voracious predators, corals have developed several lines of defense. One is to armour themselves with plates and spines to protect their fleshy polyps.  Another is to mount a chemical defense, usually involving lots of--you guessed it--slime!

Bamboo corals are probably the record setting slime producers, but interestingly one of our red-tree corals also produced a large quantity of slime, while none of the others did. This is a curious observation, and we are not sure why this difference exists. Perhaps the slime is a characteristic of a different species. Gross examintion of the branches indicated that the slime producing red tree coral was a darker colour, and a quick examination of it under the microscope suggested its spicules (variously shaped spines made from calcium carbonate) were different than the other non-slime producers. 

The taxonomy of deep sea corals is still relatively poorly worked out compared to other species, and undoubtedly new species will be found and described in the coming years. Samples from our red tree corals were collected to help in identifying them--and if it turns out that this is a new species, well we have a name ready - ghostbusteri.  Scientists commonly latinize a word pertaining to a key distinctive feature when naming a new species - such as slime. Who ya gonna call? 

We will send our samples to experts at the Smithsonian Institute in Washington D.C.