molluscs

Geukensia demissa

Trophic Level: Herbivore

Characteristics: bivalve; thin, long shells with brown, green, or purple exterior and iridescent interior

Range: Atlantic coast of the U.S. until northern FL

Size: shells average 2-5in (5-13cm) in length

Habitat: marsh platform

Fun Fact: grows in clusters near the base of Spartina plants and holds fast to the plant’s roots with byssal threads

Where It's Found: Low marsh

Lolliguncula brevis

Trophic Level: Carnivore

Characteristics: cephalopod; body covered in chromatophores; large eyes; arms and tentacles surround mouth and sharp beak

Range: NJ to FL, and northern Gulf of Mexico

Size: up to 5in (13cm) in length

Habitat: estuaries, tidal creeks

Fun Fact: internal shell is referred to as the “pen shell” because it is said that sailors used to dip it in ink to write with

Where It's Found: Tidal creek

Busycotypus canaliculatus

Trophic Level: Carnivore

Characteristics: gastropod; 5-6 whorls; fine beading toward tip of spire

Range: Atlantic coast of the U.S.

Size: 4-8in (10-20cm) in length

Habitat: sand and mud flats, oyster reefs, offshore to 60ft deep

Fun Fact: uses a muscular foot to hold bivalve prey while chipping at its hinge until it can pry the shells apart

Where It's Found: Tidal creek

Crassostrea virginica

Trophic Level: Herbivore

Characteristics: bivalve; shell narrow at the hinge and widening to a rough oval shape; gray exterior with glossy white interior

Range: Atlantic coast of the U.S.

Size: shells average 2-6in (5-15cm) in length

Habitat: tidal creeks, intertidal in Southeast, also subtidal in NC

Fun Fact: oyster beds provide important living habitat for many species of fish and invertebrates

Where It's Found: Tidal creek

Ilyanassa obsoleta

Trophic Level: Detritivore

Characteristics: gastropod; black or dark brown conical shell

Range: Native to Atlantic coast of the U.S., now invasive along the Pacific coast

Size: up to 1in (3cm) in length

Habitat: intertidal mud flats

Fun Fact: highly active scavengers, swarms of mud snails will break down organic matter on the surface of the mud

Where It's Found: Tidal creek

Busycon carica

Trophic Level: Carnivore

Characteristics: gastropod; shell has an average of 6 whorls with protruding knobs evenly spaced; shell opening on the right

Range: Atlantic coast of the U.S.

Size: 4-10in (4-25cm) in length

Habitat: tidal creeks, often found on oyster reefs, up to 30ft deep

Fun Fact: lays a string of egg capsules that can often be found washed ashore

Where It's Found: Tidal creek

Littoraria irrorata

Trophic Level: Detritivore

Characteristics: gastropod; shell color dark brown to white

Range: New England to the Gulf Coast of Texas

Size: up to 1in (3cm) in length

Habitat: stalks of living and dead <em>Spartina</em>, low marsh to the upland border

Fun Fact: feeds on microalgae and detritus, plays a key role in decomposition and the recycling of marsh nutrients

Where It's Found: Low marsh, High marsh

Mercenaria mercenaria

Trophic Level: Herbivore

Characteristics: bivalve; thick oval shell with noticeable growth rings and tan exterior color

Range: Atlantic coast of the U.S., the Gulf of Mexico

Size: shells average 2-5in (5-13cm) wide

Habitat: intertidal to subtidal; coarse, shelly sand

Fun Fact: most valuable clam harvested in the US; may live more than 40 years

Where It's Found: Tidal creek