PHEW.
I have some bills to pay. This will help. And why do I have bills? Because I have spent many years studying one group of animals, and one group only.
Brittlestars, serpentstars, basketstars....ophiuroids all.
Unfortunately, frozenguy gets the check. Hope he will share some though.
Yes, what he has shown is the only tank species that is a known predator, well documented in the wild, though it may or may not be in captivity.
AND YES...
THERE IS NO BIOLOGICAL DIFFERENCE BETWEEN BRITTLESTARS AND SERPENTSTARS. IT IS A DISTINCTION MADE IN THE TRADE ONLY.
Therefore, the green brittlestar, and the green serpentstar as I know them, are the same beast. And believe me, I know quite a few of them. So, please show me the predatory green serpentstar!? It is the same critter.
"Brittlestars" are apparently those with arm spines, serpentstars are those without. This is, in fact, BS. Both have arm spines, but brittlestar hold the spines perpendicular to the arm, and serpentstars generally have shorted spines that are held adpressed, or parallel, to the arm. But they both have arm spines, and they both can be either a brittlestar or a serpenstar at any given time, with any observer. It is almost random.
The confusion comes from the common names of the group. The "Ophiuroidea" are a class of Echinoderms, that are described as "snake" or "serpent" like (the term "Ophios"is reference to this). However, all of these animals can readily autonomize, or drop arms, leading to the other common name of brittlestar.
Doesn't matter. Both the same. I can talk to you at length about it.
The green brittle/serpentstar (and YES, I have seen it called both), is more appropriately called Ophiarachna incrassata. It is a KNOWN PREDATOR in the wild. Indeed, lets know what animal we are talking about, shall we? Let's use the proper scientific Latin!! I'm game!
But, I HAVE HEARD NEARLY EVERY OTHER SPECIES OF BRITTLESTAR IN THE TRADE IMPLICATED IN SOME ATTACK. And I have every reason to believe some of the stories.
The simple fact is we are not able to study the range of behaviors and feeding strategies available to these animals in the wild, though donations such as the reward mentioned will help. I believe brittlestars are incredibly opportunistic. They will take advantage of any dead, weak or stressed animal in the tank, and they will, sometimes, take healthy animals too. They will eat a wide range of things, should the opportunity presents itself. Indeed, we are learning that more and more species are quite predatory. Generally, they will be drawn to dying things, acting as opportunistic scavengers, but this does not describe all individuals, or all species in any given situation.
The purpose in nature is to grow large and reproduce...you don't do this by letting a free meal get away.
rescue, you may wish to elaborate on your situation, the age of the tank, water parameters, fish involved, etc. Never jump to conclusions, or you may miss the true answer. What sort of brittlestar do you have? Do you feed it? And yes, CBS also are known to eat fish now and again.
jwishy, all I can ask is that you learn to contribute in a productive manner. I suspect you are not one of my colleagues....another brittlestar researcher (get my drift?). You are entitled to your opinion regarding the predatory nature of certain species. Lord knows I think most are wrongly implicated in such attacks, and I can be rather abrupt at these times, but there are overall, constructive ways to provide input.