Callianassidae Family of Ghost Shrimp

Bay Ghost Shrimp, Neotrypaea californiensis. A representative of the Callianassidae Family of Ghost Shrimp.

Phylogeny:  Ghost Shrimp are a member of the Callianassidae Family. The Family is a taxonomically active with multiple subfamilies and reclassifications on-going. Like crabs, crayfish and lobsters the Ghost Shrimp belong to the Phylum Arthropoda. They are in the Class Malacostraca and the Order Decapoda.

Distribution:  Ghost Shrimp are found worldwide in temperate and tropical seas from the intertidal zone intertidally (or subtidally) to depths as great as 1,050 m (3,444 feet). There are two hundred and thirty-four species in the Callianassidae Family of which five are found along Mexico’s Pacific Coast.

Morphology:  Callianassid have 5 head segments, 8 thoracic segments, 6 abdominal segments, 5 pairs of appendages function as legs (pereiopods), 3 pairs function as mouth parts (maxillipeds), and 1 pair is modified into enlarged unequally sized pincers (chalae). The first abdominal segment is shorter and narrower than the remaining segments; the abdominal appendages are not oar-shaped. The head and thorax are usually combined as a cephalothorax. Their head includes a pair of antennae, a pair of antennules, and the mouth. These animals have a two chambered stomach. Ghost Shrimp can reach a maximum of 15 cm (5.9 inches) in length. The Ghost Shrimp are pale to whitish in color, from which they derive their name.

Ecosystems Roles:  Ghost Shrimp are burrowers, that usually reside in extensive burrows in sand or mud substrate. Most burrows are branched, with multiple entrances. Some burrows extend 75 cm (2 feet 4 inches) below the surface of the substrate. Some species may be found in burrows in porous rock or coral, or under rocks. They utilize the hairs on their legs to feed on detritus and plankton, which they filter from the ambient water, or the sediment. They often store dead plant matter in their burrows. In turn Ghost Shrimp are preyed upon by crustaceans, fish, and mollusks. Ghost Shrimp often share their burrows with other animals, including clams, gobies,  pistol shrimp and polychaeta worms. The burrowing activity of Ghost Shrimp influences the chemical and geophysical properties of the sediment (bioturbation), and plays an important ecological role.