Double the sea urchins


Sea urchin Parasalenia gratiosa.
Image: Gary Cranitch

 

Friday 20 February 2009
 
WHEN Ashley Miskelly arrived on Lizard Island, the station had a list of 21 known species of sea urchin from the area.
 
That list now stands at about 40 species –with more likely to follow.
 
 Among those species was one, Echinoneus abnormalis, which Ashley has only found close to Australia before.
 
That find was in 1999, halfway to New Caledonia. This time around it's right on the Great Barrier Reef.
 
"It's the first time it's been found in Australian waters," he said.
 
As for increasing the species list, Ashley has a simple explanation – he just knows where to look.
 
"This area's really high in echinoderm biodiversity," he said.
 
However the types of sea urchins he is adding to the list – mostly "infaunal detritovores" – are very small and burrow into the sand.
 
Infaunal detritovores are bilaterally symmetrical, same on both sides of a central axis, and include heart urchins and sand dollars.
 
"They tend to be overlooked. To find them you've really got to dig," Ashley said.