Mollusca · mollusks

Knobbed whelk

Busycon carica

Busyconidae · busycon whelksIUCN: Not evaluated
Knobbed whelk
Photo: JoshuaDavisPhotography. COM · CC BY-SA 2.0 · Wikimedia Commons · resized

A heavy, left-handed whelk with knobs on its shoulder, found from Massachusetts to Florida.

Fun factIt is the state shell of New Jersey and Georgia.

Waters
Northeast US, Northwest Atlantic
Depth zone
Coastal shallows & estuaries
Diet
Clams & oysters
Size
Shell up to 23 cm

Classification

Mollusca › Gastropoda › Neogastropoda › Busyconidae

  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 Gastropoda snails & slugs
    • Snails and slugs, most with a single, often coiled shell
    • Body twists 180 degrees during development (torsion)
    • Crawl on a broad muscular foot
  7. Subclass Caenogastropoda whelks, periwinkles & kin
    • Most have a single gill and a shell door (operculum)
    • Many have a siphon to sample water
    • Includes periwinkles, whelks, and conchs
  8. Order Neogastropoda whelks & cone snails
    • Mostly predators and scavengers
    • Long siphon in a groove (siphonal canal) at the shell opening
  9. Family Busyconidae busycon whelks
    • Large whelks of the western Atlantic
    • Pear-shaped shells with a long siphonal canal
  10. Genus Busycon
    • Species in the same genus are very close relatives and often look alike.
  11. Species Busycon carica Knobbed whelk

Closest relatives in the guide