Axiidae Family of Mud Shrimp

One Mud Shrimp of the Axiidae Family can be found in this website:

Keeled Mud Lobster, Calocarides quinqueseriatus. A representative of the Axiidae Family of Burrowing Shrimp, Ghost Shrimp and Mud Shrimp.

Phylogeny:  The Axiids are a member of the Axiidae Family of Burrowing Shrimp, Ghost Shrimp and Mud Shrimp in the phylum Arthropoda. They are in the subphylum crustacea, the class Malacostraca and order Decapoda. They are in the suborder Pleocyemata and the infraorder Axiidea. The Axiidae Family is one of eleven families in this infraorder. The Axiidae Family is large, with forty-eight genera and around two hundred five species. Axiid Shrimps are only distantly related to true shrimp.

Morphology:  Axiids have a shrimp-like body with an extended abdomen and a large abdominal pleura. Their head has six segments, the thorax eight segments, the abdomen six segments, they possess antennules, antennae, compound stalked or sessile eyes and mouth parts; they usually have eight pairs of thoracic legs. The front three pairs of legs (maxillipeds) function as mouth parts. And one pair (chelipeds) serve as enlarged pincers or claws. The rostrum is, at least, twice as long as it is wide, with five or six “teeth” on each side. The first two pairs of legs have pincers (chelae), and the remaining three pairs are simple. They have well developed tail fan utilized for swimming.  Axiids may be white, red, pink, orange, or brown in color. The largest species in the Axiidae Family reaches a maximum of 35 cm (14 inches) in length. Many species in the Axiidae Family demonstrate sexual dimorphism with the female being larger than the males and the males having a larger major cheliped (claw).

Distribution: Axiids are found on soft substrates within burrows that may be simple “U” shaped tunnels, intricately branched tunnels or caverns. They are found from the intertidal zone to depths of greater than 2,000 m (6,560 feet), though the great majority are found in water less than 183 m (600 feet). Some are found in protected bays and estuaries, while others are found in the open ocean. Axiids are found worldwide in tropical to temperate seas.  Seven species of the Axiidae Family are found in Mexican waters.

Reproduction: Axiids may be gonochoric (male or female for life) or simultaneous hermaphrodites (having both male and female reproductive organs).  Reproduction is sexual with an indirect transfer of sperm and external fertilization. The female carries the fertilized eggs attached to her abdomen. The eggs hatch into planktonic larvae.

Ecosystem Roles:  Axiids feed primarily on plant material that is found either in the form of detritus or is suspended in the water column. In turn they are preyed up on shore birds, fish, and octopus.