Peacock Mantis Shrimp, Hemisquilla californiensis

Peacock Mantis Shrimp, Hemisquilla californiensis. Length: 30 cm (11.8 inches). Capable of moving faster than Usain Bolt!

Phylogeny: The Peacock  Mantis Shrimp, Hemisquilla californiensis, Stephenson, 1967, is a stomatopod, and a member of the Hemisquillidae Family of  Smashing Mantis Shrimps.  Hemisquilla is the only genus in this Family, and it is comprised of four species. These four species are widely distributed around the world and are thought to be relict species. This species is also known as the Blueleg Mantis Shrimp. In Mexico it is called estomatópodo pavorreal . Until 1967 this species was considered a subspecies of Hemisquilla ensigera, but now it is recognized as a separate species.

Morphology:  As the name might suggest, the Peacock Mantis Shrimp is the most colorful of the stomatopods in the region. The uropods are yellow, orange, and blue. The legs may be blue to purple. The second pair of thoracic appendages are yellow. Most of the rest of the body is brownish, though some specimens have pink to red color on the carapace. Their claws are sharp, but not barbed. Peacock Mantis Shrimp reach a maximum of 32 cm (12.6 inches) in length. While these mantis shrimp are smashers, their second pair of thoracic appendages (raptorial claws) are sharp and can inflict serious lacerations if not handled carefully.

Habitat and Distribution: Peacock Mantis Shrimp live in deep borrows in sand, mud, or sand/shell mix. They often plug the entrance to their burrow with a mucous/sand plug. They are nocturnal. They range in depth from 33 m (108 feet) to 106 m (348 feet), though some sources place them as shallow as 3 m (10 feet). One record does exist of an individual brought up in a shrimp trawl from 1800 m (5,905 feet) in the Gulf of California. They are found from Southern California to Panama. In Mexican waters they are present along the entire Pacific coast, with the exception of the Gulf of California, north of Bahia de Los Angeles.

Diet:  Peacock Mantis Shrimps leave their burrows at night to forage. They feed on shrimp, crabs, bivalves, and snails. They smash the shell by grasping their prey with their raptorial claws and smashing it against a rock.

Predators: Peacock Mantis Shrimp are prey for larger fish, such as groupers, wreckfish, sharks, and rays. Peacock Mantis Shrimps are capable of producing a low frequency rumbling sound that may serve to dissuade predators or mark territory.

Reproduction: Peacock Mantis Shrimp are gonochoric (either male or female for life). They reproduce sexually. While mating and brooding, usually between March and June, the males and females share a burrow. They frequently cap the top of the burrow during this time, to prevent predation. The males assist the females by bringing them food. The females can produce tens of thousands of eggs.  Once the eggs hatch the hatchlings drift around as plankton for a few months before settling to begin their benthic life.

Ecosystems Interactions:  We are unaware of any reports of Peacock Mantis Shrimps sharing their burrow with other species, or of other forms of commensalism.

Human Interaction:  While many species of mantis shrimps are consumed as a human food substance, Peacock Mantis Shrimp populations are too sparse to be targeted as a food species. They are caught as a bycatch by shrimp trawlers which may have some impact on local populations, especially during breeding season when many males leave their burrows to search for females. They are also occasionally caught by anglers. Because they are capable of breaking aquarium glass with their claws, they are seldom utilized by aquarists.  From a conservation perspective they are currently considered to be of Least Concern with stable, widely distributed populations.

Synonyms:  Hemisquilla ensigera californiensis