Mollusca · mollusks

Ribbed mussel

Geukensia demissa

Mytilidae · musselsIUCN: Not evaluated
Ribbed mussel
Photo: United States Geological Survey · Public domain · Wikimedia Commons · resized

A ridged mussel that lives half-buried among salt marsh cordgrass roots.

Fun factIts byssal threads bind marsh soil, and its waste fertilizes the cordgrass.

Waters
Northeast US, Northwest Atlantic
Depth zone
Intertidal shore
Diet
Plankton (filter feeder)
Size
Shell up to 10 cm

Classification

Mollusca › Bivalvia › Mytilidae

  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 Pteriomorphia oysters, scallops & mussels
    • Often attach to surfaces with threads (byssus) or cement
    • Includes oysters, scallops, mussels, and pearl oysters
  8. Family Mytilidae mussels
    • Mussels: elongated shells
    • Attach with strong byssal threads, forming dense beds
  9. Genus Geukensia
    • Species in the same genus are very close relatives and often look alike.
  10. Species Geukensia demissa Ribbed mussel

Closest relatives in the guide