Some sort of bivalve?

[fnerg]

I see these guys all over the place, there's bunches of them at Saltwater State Park. Are they some sort of scallop? This one was at Cove 2, on one of the cinderblocks along the boundary line.




I saw this on the pilings at 100 feet. Is it some sort of tubeworm spawning thing?

Here's the rest of the shots from that dive:
http://www.flickr.com/photos/fnerg/sets ... 980101710/

I managed to get an okay shot of a northern clingfish, and a northern ronquil too!

[oldsalt]

I can't tell for sure from the picture, but your bivalve may be a brachiopod. They are a phylum all their own. I see them often in the San Juans but not down here.
-Curt

[eliseaboo]

The top one is a type of brachiopod (or lampshell some people call them). They've got that neat groove in the shell that looks really neat! I've seen them all the way down the sound to Les Davis at least. I'm sure someone else here knows more specifically than I do. The bottom one looks like a spaghetti worm maybe?

[fnerg]

Wow, when I google brachiopod, or washington brachiopod, I get mostly images and articles about fossils. Not so much about current species. Are they really boring to study or something?

[dwashbur]

The lower one is called a terebellid worm. They burrow into the bottom and use those strings to feed. I don't pretend to know that on my own, I got it from Leslie ages ago when I asked about the same thing

[oldsalt]

Wow, when I google brachiopod, or washington brachiopod, I get mostly images and articles about fossils. Not so much about current species. Are they really boring to study or something?

My elder son majored in geology. It was neat accompanying him on field excursions in Montana and finding all of the brachiopod fossils. When I first encountered brachs on a marine biology field trip, the only student to recognize them was a geologist. That said, they are an interesting animal. In one sense they could be considered a bivalve, since the word just means "two shells". But Bivalvia also labels a class of molluscs.Brachs lack the visceral mass that characterizes molluscs, so they occupy a separate phylum. I think their ancient heritage and their uniqueness make them anything but boring, but I will let the real experts comment further.
-Curt
(also a fossil)