MV Blog

DISPLAYING POSTS TAGGED: starfish (1)

Tiny star on film

Author
by Blair
Publish date
3 July 2011
Comments
Comments (6)

In 2007, Museum Victoria research scientists described the world's tiniest starfish, the Paddle-spined Seastar. Here are three of them under the microscope last week, filmed by Ben Healley.

 

Like all starfish, these animals are powered by many legs called tube feet. Each has a sucker on the tip which is how they crawl around and hang upside down under rocks. On the video they appear transparent so are difficult to see moving out from underneath each arm. They stick to the glass and drag the animal across the surface.

They don’t have eyes but they do have eyespots. You can also see these on the video. They are the dark patches at the tip of each arm, on top of the animal. Detecting light and dark, they help the animal tell if it is under a ledge or on top of it, or whether something large, like a possible predator, is passing overhead.

Interestingly, the individual pictured in reports when this species was discovered has five legs, not six. According to MV curator Dr Tim O'Hara, "it’s typical for this species to have six arms but every now and then, you’ll get an uneven split during reproduction and end up with a five-armed individual.”

Links:

MV News: Tiny star

About this blog

Updates on what's happening at Melbourne Museum, the Immigration Museum, Scienceworks, the Royal Exhibition Building, and beyond.

Categories