Whilst I often see sea spiders (Pycnogonids) in kelp forests around the South Island, it wasn’t until I visited Antarctica that I got a little creeped out by them. Like many marine invertebrate taxa, sea spiders in Antarctica display gigantism – the largest species can have a leg span of half a meter, and bodies up to 5 cm long! It turns out I didn’t have any reason to fear for my life… these “spiders” don’t have killer venom, or spin human-sized webs. Instead they suck the juices of soft-bodied invertebrates like anemones and ascidians (sea squirts), or eat small hydroids and bryozoans. At last count there were 264 different species of pycnogonids in Antarctic and sub-Antarctic waters – here are a few pictures to whet your appetite.
Colossendeis sp. Photo: Dale Stokes
Pycnogonid loving - all legs... the males carry the fertilized eggs around until they hatch. Pycnogonids don't have a pelagic larval stage, so don't spread very far. Photo: Dale Stokes
They look pretty cool. It’s a shame about the lack of venom. Then you could pretend they were really scary.
I’ve got to wonder though, how you take photos of them? There must be quite a few technical challenges to taking photos in the Antarctic waters.