Undescribed fluorescent Palythoa species photographed along the shoreline of PortMiami.

We are happy to announce the publication of a scientific paper in Springer Nature analyzing the presence and potency of palytoxin (PLTX) in Palythoa spp. and Zoanthus spp. Zoantharians conducted by the Mediterranean Institute of Oceanography and Coral Biome in Marseilles, France. PLTX is one of the most potent toxins known on the planet. It is an extremely large and complex organic compound that has been described by biochemists as the ‘Mt. Everest of organic synthesis’. An organism that naturally produces large amounts of PLTX is of great importance for research scientists to better understand its pharmacology. PLTX has been found to have toxic effects on head and neck tumors, and therefore warrants further pharmaceutical investigation.

Initially, this compound was blue-prospected in Hawaii where native Hawaiian people used the the mucous of Palythoa found in a very specific (and taboo) tide pool (known as limu-make-o-Hana, the ‘seaweed of death of Hana’) to coat their spear points before battle. So taboo was this tide pool for outsiders, that when scientists sampled the Palythoa in 1961, they found their lab burned to the ground on the same day. A reminder to scientists to respect native wisdom, culture, and practices when performing science on other cultures’ land!

In this paper we found that an undescribed species (Palythoa aff. clavata) we sampled from PortMiami in 2012 was found to have five times the concentration of the notorious Hawaiian species Palythoa toxica. The experiment also tried to determine whether PLTX was produced by symbiotic microbial symbionts / zooxanthellae, or by the organism itself. Highest concentrations of PLTX were found within the tissue itself, and isolated cultures of zooxanthellae from these polyps failed to produce PLTX in the laboratory. This suggests, but does not confirm, that the Palythoa polyps themselves are producing this toxin. While the mechanism of its biosynthesis remains unknown, it highlights how Miami’s urban marine environs hold important scientific discoveries still waiting to be uncovered.

Read ‘Symbiodiniaceae diversity and characterization of palytoxin in various zoantharians (Anthozoa, Hexacorallia)’:

Colins-Palytoxin-Paper

Unidentified ‘Butterfly’ Palthoas.

Recently while diving off of Key West, I was fortunate to come upon a rare and unidentified species of Palythoa. This was the first time that I have come upon this type in five years of frequent diving throughout the Florida Keys. Apparently it is less rare elsewhere in the Caribbean, but as of now has yet to be properly identified by a zoanthid taxonomist. On its particular patch of reef it was relatively abundant, despite being completely absent in seemingly identical reefs in the surrounding area. And while it might seem logical that it only takes one lucky zoanthid larvae to ultimately colonize a large area, it seems that there were at least 2 separate morphs cohabiting the area, which makes its complete absence from other nearby reefs compelling. And while Caribbean Palythoa display morphologies that seem to overlap, these particular Palythoa have a few traits that make it noticeably distinct:

• Small size (1/4″-3/8″ disc diameter)
• Translucent oral disc, often with teal-bluish iridescent sheen
• Distinctive white splotch, often butterfly shaped
• Eyelash-like tentacles

But considering that the morphologies of Caribbean Palythoa species seem to blur together, genetic analysis will be the most reliable way to determine species-hood. Fortunately our friend James Reimer is a zoanthid expert in Japan’s Ryuku Islands with access to such equipment and expertise. In addition to sending him samples of this Palythoa morph, we will also include a variety of other local Palythoa morphs to see just how distinct the individual species are.