Skeleton shrimp
Encyclopedia
Skeleton shrimp are marine crustacean
s of the infraorder Caprellida. The name denotes the threadlike slender body which allows them to virtually disappear among the fine filaments of seaweed, hydroids
and bryozoans.
, hydroid
s and bryozoa
ns. They are typically seen attached to substrate by their grasping appendage
s called the pereiopods.
Caprellids are omnivorous, feeding on diatoms, detritus, protozoans, smaller amphipods, and crustacean larvae
. Some species are filter feeder
s, using their antennae
to filter food from the water or scrape it off the substrate. Most species are predators that sit and wait like a praying mantis, with their gnathopods ready to snatch any smaller invertebrates which come along. They accentuate their adaptive form and colouration by assuming an angular pose, resembling that of the fronds among which they live. They remain motionless for long periods of time while waiting to ambush their prey, often protozoa
or small worms.
Caprellids are typically preyed upon by surf perch, shrimp
, nudibranch
s such as the lion nudibranch Melibe leonina
and brooding anenomes (Epiactis prolifera
). Since they often inhabit eelgrass beds with sessile jellyfish, (Halicylystus and Thaumatoscyphus), the caprellids frequently become jellyfish food. Caprellids are not normally considered a main source of food for fish, but when shiner perch
(Cymatogaster aggregata) migrate into the eelgrass beds for reproduction, they target caprellids.
. The young will hatch and emerged as juvenile adults. After mating, the female in some species have been known to kill the males by injecting venom from a claw within their gnathopod.
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s of the infraorder Caprellida. The name denotes the threadlike slender body which allows them to virtually disappear among the fine filaments of seaweed, hydroids
Hydrozoa
Hydrozoa are a taxonomic class of very small, predatory animals which can be solitary or colonial and which mostly live in saltwater. A few genera within this class live in freshwater...
and bryozoans.
Ecology
Caprellids are exclusively marine and are found in oceans worldwide. A few species are found in the ocean depths, but most prefer low intertidal zones and subtidal waters among eelgrassZostera
Zostera is a small genus of widely distributed seagrass, commonly called marine eelgrass or simply eelgrass . The genus Zostera contains sixteen species.-Ecology:Zostera is found on sandy substrates or in estuaries submerged or partially floating...
, hydroid
Hydroid
-Marine biology:Hydroids are a life stage for most animals of class Hydrozoa, small predators related to jellyfish.-Botany:In mosses, hydroids form the innermost layer of the stem of long, colourless, thin walled cells of small diameter.The cells are dead and lack protoplasm.They function as water...
s and bryozoa
Bryozoa
The Bryozoa, also known as Ectoprocta or commonly as moss animals, are a phylum of aquatic invertebrate animals. Typically about long, they are filter feeders that sieve food particles out of the water using a retractable lophophore, a "crown" of tentacles lined with cilia...
ns. They are typically seen attached to substrate by their grasping appendage
Appendage
In invertebrate biology, an appendage is an external body part, or natural prolongation, that protrudes from an organism's body . It is a general term that covers any of the homologous body parts that may extend from a body segment...
s called the pereiopods.
Caprellids are omnivorous, feeding on diatoms, detritus, protozoans, smaller amphipods, and crustacean larvae
Crustacean larvae
Crustaceans may pass through a number of larval and immature stages between hatching from their eggs and reaching their adult form. Each of the stages is separated by a moult, in which the hard exoskeleton is shed to allow the animal to grow...
. Some species are filter feeder
Filter feeder
Filter feeders are animals that feed by straining suspended matter and food particles from water, typically by passing the water over a specialized filtering structure. Some animals that use this method of feeding are clams, krill, sponges, baleen whales, and many fish and some sharks. Some birds,...
s, using their antennae
Antenna (biology)
Antennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....
to filter food from the water or scrape it off the substrate. Most species are predators that sit and wait like a praying mantis, with their gnathopods ready to snatch any smaller invertebrates which come along. They accentuate their adaptive form and colouration by assuming an angular pose, resembling that of the fronds among which they live. They remain motionless for long periods of time while waiting to ambush their prey, often protozoa
Protozoa
Protozoa are a diverse group of single-cells eukaryotic organisms, many of which are motile. Throughout history, protozoa have been defined as single-cell protists with animal-like behavior, e.g., movement...
or small worms.
Caprellids are typically preyed upon by surf perch, shrimp
Shrimp
Shrimp are swimming, decapod crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Adult shrimp are filter feeding benthic animals living close to the bottom. They can live in schools and can swim rapidly backwards. Shrimp are an important...
, nudibranch
Nudibranch
A nudibranch is a member of what is now a taxonomic clade, and what was previously a suborder, of soft-bodied, marine gastropod mollusks which shed their shell after their larval stage. They are noted for their often extraordinary colors and striking forms...
s such as the lion nudibranch Melibe leonina
Melibe leonina
Melibe leonina, common names the "hooded nudibranch" or the "lion's mane nudibranch", is a species of predatory sea slug, specifically a nudibranch, a marine gastropod mollusk in the family Tethydidae.- Description :...
and brooding anenomes (Epiactis prolifera
Epiactis prolifera
Epiactis prolifera, the brooding, proliferating or small green anemone, is a species of marine invertebrate in the family Actiniidae...
). Since they often inhabit eelgrass beds with sessile jellyfish, (Halicylystus and Thaumatoscyphus), the caprellids frequently become jellyfish food. Caprellids are not normally considered a main source of food for fish, but when shiner perch
Shiner perch
The shiner perch Cymatogaster aggregata is a common surfperch found in estuaries, lagoons, and coastal streams along the Pacific coast from Alaska to Baja California...
(Cymatogaster aggregata) migrate into the eelgrass beds for reproduction, they target caprellids.
Reproduction and growth
Mating can only occur when the female is between the new and hardened exoskeletons, which both male and female do in order to grow. After mating the female will brood the fertilized eggs within her brood pouchBrood pouch (Peracarida)
The marsupium or brood pouch, is a characteristic feature of Peracarida, including the orders Amphipoda, Isopoda and Cumacea. It is an egg chamber formed by oostegites, which are appendices which are attached to the coxae of the first pereiopods...
. The young will hatch and emerged as juvenile adults. After mating, the female in some species have been known to kill the males by injecting venom from a claw within their gnathopod.
Classification
Twelve families are currently recognised in the group:- Aetiopedesidae Myers & Lowry, 2003
- CaprellidaeCaprellidaeCaprellidae is a family of amphipods. It contains 88 genera in three subfamilies:Caprellinae*Abyssicaprella McCain, 1966*Aciconula Mayer, 1903*Aeginella Boeck, 1861*Aeginellopsis Arimoto, 1970*Aeginina Norman, 1905...
Leach, 1814 - Caprogammaridae Kudrjaschov & Vassilenko, 1966
- Cyamidae Rafinesque, 1815
- Dulichiidae Laubitz, 1983
- IsaeidaeIsaeidaeIsaeidae is a family of amphipods, containing the following genera:*Cerapopsis Della Valle, 1893*Cheirophotis Walker, 1904*Eurystheus *Isaea Milne-Edwards, 1830*Microprotopus Norman, 1867*Noenia *Podoceropsis Boeck, 1861...
Dana, 1853 - IschyroceridaeIschyroceridaeIschyroceridae is a family of amphipods. It contains the following genera:*Ambicholestes Just, 1998*Bonnierella Chevreux, 1900*Cerapus Say, 1817*Ericthonius Milne-Edwards, 1830*Ischyrocerus Krøyer, 1838*Jassa Leach, 1814...
Stebbing, 1899 - Paragammaropsidae Myers & Lowry, 2003
- Pariambidae Laubitz, 1993
- Photidae Boeck, 1871
- PodoceridaePodoceridaePodoceridae is a family of amphipods. It contains eight genera:*Cyrtophium Dana, 1852*Laetmatophilus Bruzelius, 1859*Leipsuropus Stebbing, 1899*Neoxenodice Schellenberg, 1926*Parunciola Chevreux, 1911...
Leach, 1814 - Rakiroidae Myers & Lowry, 2003