''Hymenocera picta'', commonly known as the harlequin shrimp, is a species of
saltwater shrimp
Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are refer ...
found at
coral reefs in the tropical
Indian and
Pacific Oceans. It is usually considered the only species in the genus ''Hymenocera'',
but some split it into two species: ''H. picta'' from the central and east Pacific, where the spots are deep pinkish-purple with a yellow edge, and ''H. elegans'' from the Indian Ocean and west Pacific, where the spots are more brownish and have a blue edge.
[Debelius, H. (2001). ''Crustacea: Guide to the World.'' Pp. 198-199. ] They reach about in length, live in pairs, and feed exclusively on
starfish
Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea (). Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish ...
,
[ including ]crown-of-thorns starfish
The crown-of-thorns starfish (frequently abbreviated to COTS), ''Acanthaster planci'', is a large starfish that preys upon hard, or stony, coral polyps (Scleractinia). The crown-of-thorns starfish receives its name from venomous thorn-like spine ...
. They do seem to prefer smaller, more sedentary starfish
Starfish or sea stars are star-shaped echinoderms belonging to the class Asteroidea (). Common usage frequently finds these names being also applied to ophiuroids, which are correctly referred to as brittle stars or basket stars. Starfish ...
, but as these generally are not sufficiently numerous for their needs, they commonly attack crown-of-thorns starfish
The crown-of-thorns starfish (frequently abbreviated to COTS), ''Acanthaster planci'', is a large starfish that preys upon hard, or stony, coral polyps (Scleractinia). The crown-of-thorns starfish receives its name from venomous thorn-like spine ...
, both reducing its consumption of coral while under attack, and killing it within a few days.[Glynn, P.W., Interactions between Acanthaster and Hymenocera in the field and laboratory. In: D.L. Taylor (ed.) Proceedings of Third International Coral Reef Symposium Vol. 1: Biology. Rosenstiel School of Marine and Atmospheric Science, Miami, Florida. pp. 209-216. 1977]
Description
The harlequin shrimp is usually cream colored or white with occasional spots. Around the Pacific Ocean, many of these shrimp have red spots, while the Indian Ocean shrimp typically have purple spots; the Hawaiian ''H. picta'' has purple and red spots on its body, the shrimp has two walking legs on each side and large claws, or chelipoda. The claws and eyes appear to look flattened and thin. On its head, the shrimp has "petal-like sensory antennules" to smell out prey. Its body usually reaches up to 5 cm (2 in), and the male is slightly smaller than the female.[[University of Hawaii Mãnoa Education Department. "Marine Life Profile: Harlequin Shrimp." Waikiki Aquarium, n.d. Web
Image:Hymenocera picta.jpg , Couple of ''Hymenocera picta'' hunting a sea star
Image:Harlequin Shrimp 1.jpg , Harlequin shrimp of Indian Ocean/West Pacific population
Image:Hymenocera picta55.jpg
Image:Harlequin Shrimps - Hymenocera Elegans.jpg
]
Habitat
These shrimp are typically found in Hawaii through the Indo-Pacific below the intertidal zone on coral reefs.
Diet
Harlequin shrimp usually only feed on starfish. They are very skilled at flipping over a slow starfish on its back, and eating the tube feet and soft tissues until it reaches the central disk. They, usually one female and one male, use their claws to pierce the tough skin and feeding legs to help them maneuver the starfish. Sometimes, the starfish will shed the arm that the shrimp attacked and regrow it, but it is usually too wounded to regrow. They may also feed on sea urchins, because they have tube feet, as well, but that is rare and only if starfish are not available.
Behavior/reproduction
The harlequin shrimp moves at a very slow pace and in waves. It also may have toxins from its prey (the starfish), which could make it distasteful and potentially dangerous for predators. The shrimp also moves its claws almost constantly. Females are larger and have colored abdominal plates unlike the males. The female produces between 100 and 5,000 eggs per season depending on environmental factors. The male and female are often seen together in the wild, and work together to not only reproduce, but also to forage.["Harlequin Shrimp." Harlequin Shrimp. N.p., n.d. Web. 30 Sept. 2013.
]
References
External links
Video of an Adult and juvenile harlequin shrimp
hosted by YouTube
*[University of Hawaii Mãnoa Education Department. "Marine Life Profile: Harlequin Shrimp." Waikiki Aquarium, n.d. Web.
*"Harlequin Shrimp - Hymenocera Picta." FreshMarine.com. N.p., n.d. Web. 30 Sept. 2013. .
*"Harlequin Shrimp." Harlequin Shrimp. N.p., n.d. Web. 30 Sept. 2013. ..
*
{{Taxonbar, from=Q2715679
Palaemonoidea
Monotypic arthropod genera
Crustaceans described in 1819