Squilla

Squilla is a genus of mantis shrimp found in marine habitats in tropical and sub-tropical climates all over the world, such as the Indian Ocean and Mediterranean sea. They are often caught unintentionally by fisheries in their climate, and they are not used for human food or fish meal, though valuable compounds such as chitin and chitosan can be extracted from their shells. The genus first appeared in the fossil record 145 million years ago.

Squilla is a genus of mantis shrimp found in marine habitats in tropical and sub-tropical climates all over the world, such as the Indian Ocean and Mediterranean sea. They are often caught unintentionally by fisheries in their climate, and they are not used for human food or fish meal, though valuable compounds such as chitin and chitosan can be extracted from their shells. The genus first appeared in the fossil record 145 million years ago. ==Taxonomy== This genus includes the following species: Squilla aculeata Bigelow, 1893 Squilla biformis Bigelow, 1891 Squilla bigelowi Schmitt, 1940 Squilla brasiliensis Calman, 1917 Squilla cadenati Manning, 1970 Squilla caribaea Manning, 1969 Squilla chydaea Manning, 1962 Squilla deceptrix Manning, 1969 Squilla discors Manning, 1962 Squilla edentata (Lunz, 1937) Squilla empusa Say, 1818 Squilla grenadensis Manning, 1969 Squilla hancocki Schmitt, 1940 Squilla intermedia Bigelow, 1893 Squilla latreillei Squilla lijdingi Holthuis, 1959 Squilla mantis (Linnaeus, 1758) Squilla mantoidea Bigelow, 1893 Squilla obtusa Holthuis, 1959 Squilla panamensis Bigelow, 1891 Squilla parva Bigelow, 1891 Squilla rugosa Bigelow, 1893 Squilla surinamica Holthuis, 1959 Squilla tiburonensis Schmitt, 1940 ==Description== Though the many species of the Squilla genus vary greatly in location, they are all defined by a few common shared traits, or synapomorphies. One of those notable ones is the number of teeth on their claw, which tends to be of a middling size. Because Squilla lack a hardened "smashing" appendage like some of their fellow stomatopod genera, they cannot break open hard shells, and thus largely subsist on soft-bodied prey for food. The claw of the Squilla genus is known to have six teeth. Another defining trait is the lack of a raised ridge in the exoskeleton of Squilla — or rather, the extension of the ridge over the entire exoskeleton, as such creating the appearance of the lack of a ridge. Often referred to as a "carina", this ridge can be used to differentiate Squilla from other similar stomatopods. Aside from these major features used to differentiate Squilla, other features include a tail plate with four to six spines, unlike the fused tail plates found in other stomatopods, and shorter antennular peduncles, which are the structures at the base of the shrimp's antennae that attach them to their head. Squilla are small, bilaterally symmetrical marine organisms, with a size range of . The males and females tend to be the same size. All the different species possess a form that is typical of most other stomatopods, consisting of extended eyestalks, a rostrum, carapace, and a raptorial claw used for hunting. Additionally, Squilla have developed a nauplius eye, which is an eye that is composed of three to four pigment ocelli. Likely, this eye only allows the organism to determine the location of a light source. This means species within the Squilla genus have poorer eyesight than their more famous counterparts of the Odontodactylus genus, which can see more colors than even humans. ==References==

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