Squillidae Family of Mantis Shrimp
Two Mantis Shrimp of the Sqillidae Family can be found in this website:
Phylogeny: Squillid Mantis Shrimp of the Squillidae Family are in the phylum Arthropoda. They are in the subphylum Crustacea, the superclass Multicrustacea, the class Malacostraca, the subclass Hoplocarida, the order Stomatopoda, the suborder Unipeltata, and the superfamily Squilloidea. The Squillidae Family is the only family in this superfamily. The Squillidae Family is large, with forty-seven genera and around one hundred ninety-four species. Mantis Shrimp Stomatopods are separated into two categories based on the second pair of thoracic appendages – Spearers and Smashers. Spearers have barbed appendages that they use to spear soft prey such as fish. Smashers have a thickened portion at the “elbow” of the appendage and they strike hard shelled prey with a force equal to that of a small caliber bullet. Squillid Mantis Shrimp are spearers. The name Squillidae comes from both Greek and Latin and means “prawn”, “shrimp”, “lobster”, or “sea onion”. Mantis Shrimp derive their common name from the resemblance of their “arms” and stalked eyes to that of Praying Mantis insects.
Morphology: Squillid Mantis Shrimp have 5 head segments, 8 thoracic segments, and 6 abdominal segments. The head and thorax are combined as a cephalothorax. The head includes a pair of antennae, a pair of antennules, and mouth parts. The second pair of thoracic appendages are the “arms” used for spearing prey and defense. The next 4 pairs of thoracic appendages are subchelate (pincer-like) and are used for handling food and for burrowing. The last 3 pairs are used for walking. The uropods and telson comprise the tail fan. Squillid Mantis Shrimp are characterized by T-shaped eyes with bi-lobed corneas and a well-developed, longitudinal, dorsal, carinae (keel). They have fixed, submedian teeth on a quadriform telson and rounded posterior angles on the carapace. They have six barbs on their second thoracic appendage (raptorial claw). They have eyes that are among the most complex in the animal kingdom that can see the full range of visible light colors, as well as ultraviolet and polarized light. The Stomatopods have 15 classes of photoreceptors; humans have 4 classes. Squillid Mantis Shrimp reach a maximum length of around 40 cm (15.75 inches).
Habitat and Distribution: Squillid Mantis Shrimp are found in “U”-shaped burrows in soft-substrate, or under rocks on soft substrate. Most live in shallow waters, but some are found as deep as 500 m (1,640 feet). Squillid Mantis Shrimp are found in temperate to tropical seas. At least twenty-nine species from this family are found in Mexican waters.
Reproduction: Squillid Mantis Shrimp are gonochoric (either male or female for life). They reproduce sexually, with internal fertilization. Females carry the fertilized eggs on their front appendages (maxillipeds) inside their burrows, keeping them clean and oxygenated. The eggs develop into a planktonic larvae before they settle to the bottom and metamorphose into their adult form. While mating and brooding the males and females share a burrow. In some species, males assist the females by bringing them food. The females can produce 50,000 eggs. Some species of Squillid Mantis Shrimps are monogamous, sharing the same burrow with their partner for many years.
Ecosystems Roles: Squillid Mantis Shrimp may be nocturnal or diurnal. They are carnivorous predators that feed on cnidarians, crustaceans, and fish. In turn they are preyed upon by fish and octopus.