Mollusca · mollusks

Softshell clam

Mya arenaria

Myidae · softshell clamsIUCN: Not evaluated
Softshell clam
Photo: Author not stated on Commons · CC BY-SA 3.0 · Wikimedia Commons · resized

Also called the steamer clam. It burrows deep in mudflats with a long siphon.

Fun factWhen disturbed, it squirts water out of its siphon hole.

Waters
Northeast US, Northwest Atlantic, Northeast Atlantic
Depth zone
Intertidal shore, Coastal shallows & estuaries
Diet
Plankton (filter feeder)
Size
Shell up to 15 cm

Classification

Mollusca › Bivalvia › Myidae

  1. Kingdom Animalia animals
    • Many-celled organisms that eat other living things for energy (heterotrophs)
    • Cells have no cell walls
    • Most can move at some stage of life
  2. Clade Bilateria bilateral animals
    • Body has a left and right side that mirror each other (bilateral symmetry)
    • Head end with concentrated nerves; three tissue layers
    • Includes about 99% of all living animal species
  3. Clade Protostomia protostomes
    • In the embryo, the first opening usually becomes the mouth
    • Main nerve cord runs along the belly (ventral)
    • Includes mollusks, worms, and arthropods
  4. Clade Spiralia mollusks, worms & kin
    • Embryos usually divide in a spiral pattern (spiral cleavage)
    • Many have a swimming larva with a band of cilia (trochophore)
    • Includes mollusks and segmented worms
  5. Phylum Mollusca mollusks
    • Soft body with a muscular foot and a fold of tissue (mantle) that makes the shell
    • Most have a rasping, tongue-like ribbon of teeth (radula)
    • Includes snails, clams, octopuses, and chitons
  6. Class Bivalvia clams, oysters & kin
    • Body enclosed in two hinged shells (valves)
    • No head and no radula
    • Most filter food from water with large gills
  7. Subclass Heterodonta clams & cockles
    • Hinge has distinct cardinal and lateral teeth
    • Many burrow in sediment using a long siphon
    • Includes clams and cockles
  8. Family Myidae softshell clams
    • Softshell clams: thin, gaping shells
    • Burrow deep with a long siphon that can't fully retract
  9. Genus Mya
    • Species in the same genus are very close relatives and often look alike.
  10. Species Mya arenaria Softshell clam

Closest relatives in the guide