The following image shows the general morphology of shrimp of the Caridina genus.
The cephalothorax is the fused head and thorax of the shrimp, containing organs such as the heart.
The carapace is the section of the hard chitinous cuticle that covers the cephalothorax, protecting its soft tissues.
The rostrum is the region of the carapace that extends past the eyes and projects ahead of the shrimp like a beak.
The eyes of a shrimp are used to sense light and changes in light. They are compound eyes, and are usually stalked.
The antennae are paired appendages used to sense the surroundings. These are found on the antennal spines.
The antennules are small antennae found on the antennular peduncles.
Maxillipeds are appendages afore the pereiopods that assist in feeding.
Pereiopods are the legs of the shrimp. The hind three pairs are used for locomotion, whereas the front two pairs are more concerned with gathering food. These front legs often bear claws (known as chelae) or fans, and are known as as chelipeds.
Pleopods are the ‘swimmerets’ of the shrimp, and are used for swimming. Females also use the pleopods for carrying eggs when brooding.
The abdomen is the lower section of the body of the shrimp, which contains the digestive tract and reproductive organs.
The abdominal somites are the hard segmental plates of cuticle that cover the abdomen, protecting the tissue underneath but allowing for movement.
The tailfan of a shrimp is simply its paddle-like ‘tail’, consisting of the telson and a pair of uropods that flank it. The tailfan allows the shrimp to steer whilst swimming with rhythmic fanning of the pleopods. It also allows the shrimp to propel itself extremely quickly in ‘flicking’ motions by bending its body at the abdomen and straightening it. This is known as the caridoid escape reaction.
The uropods have two sections: the endopod, which is closest to the telson, and the exopod, which is furthest from the telson.
The telson is the extension past the abdominal somites.
- “The Raffles Bulletin of Zoology 2009 57(2): 343-452
Diagram showing Caridina species morphology.