Clam wont stay upright

[Clyde]

I m wondering.. is it a squasamosa or a maxima ?

it doesnt open as wide as my green squas clam this tan one keeps tipping over, or huffing deeper and deeper inthe sand, now I m wondering is it a maxima, and its trying to find a rock to latch on ? or is it showing displeasure and wants a new place ?

[Clyde]

oops forgot to add the clam pict

http://www.cityofacros.com/ReefCentralPicts/tanclam.jpg

[chromis]

pic dosnt work for me, I think shots of the byssal openings might help....