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crustacea text index | photo index
Phylum Arthropoda > Subphylum Crustacea > Class Cirripedia
Photo index of barnacles on Singapore shores

Acorn barnacles

Star barnacles

Volcano barnacles
To about 1 cm across. Conical shell made up of plates. Commonly seen on boulders on many of our shores usually crowded in lower portions and shaded crevices. Also on living crabs and living snails. 0.5-1cm across. Flatter shell forms star-like rays where it attaches to the rock. Operculum conical and protrudes from the opening. Usually found higher up on rocks and walls in small crowded clusters. To about 3cm across. Tall conical shells not made up of plates, with a ridged texture, small shell opening operculum recessed. On large boulders.    

Stalked barnacles

Parasitic barnacles

Coral barnacles

Sponge barnacles
Membranobalanus longirostrum

About 2cm. Usually attached to hard surfaces that float in the open sea, and rarely found on the shore. Shells thin made up of several plates, on a leathery stalk. Sometimes seen on large objects that have been floating in the open sea. Barnacle is invisible, but eventually produces tiny egg sacs that emerge through the joints of the infected crab. Infected crabs sometimes seen on our Northern shores. Tiny slits (0.2cm) sometimes blue on the surface of hard corals. Sometimes seen on our Southern shores. Tiny feet (0.5cm long) with white spots, sticking o ut of holes in the Chocolate sponge. Sometimes seen on some of our shores.  

These are NOT barnacles

Phylum Mollusca

Slipper snails
Phylum Mollusca
Family Crepidulidae

Phylum Mollusca
Family Ostreidae

Jingle shell snail
Phylum Mollusca
Family Anomiidae
Also found on rocks, near barnacles. These are snails that can move around at high tide. These are snails that settle inside shells occupied by a hermit crab. These are bivalves that settle on rocks. These are bivalves that settle under stones, on mangrove tree trunks and leaves.  

how to tell apart limpets and barnacles

photo index of
crustaceans on this site
all crustaceans

all shrimps and shrimp-like

Crabs and crab-like
all crabs and crab-like


Other crustaceans
others crustaceans
sea slaters, beachfleas, mussel shrimps
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