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


Acorn barnacles
Balanus
sp.

Star barnacles
Cthalamus
sp.

Volcano barnacles
Tetraclita
sp.
   
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
Lepas
sp.


Parasitic barnacles
Thompsonia
sp.


Coral barnacles
Pygoma
sp.


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

Limpets
Phylum Mollusca

Slipper snails
Phylum Mollusca
Family Crepidulidae

Oysters
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
Crustaceans
all crustaceans

Shrimps
all shrimps and shrimp-like


Crabs and crab-like
all crabs and crab-like

Barnacles
barnacles

Other crustaceans
others crustaceans
sea slaters, beachfleas, mussel shrimps
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