Caprellidae is a

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

amphipods Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far descri ...

commonly known as skeleton shrimps. Their

common name In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contra ...

denotes the threadlike slender body which allows them to virtually disappear among the fine filaments of seaweed,

hydroids Hydroids are a life stage for most animals of the class Hydrozoa, small predators related to jellyfish. Some hydroids such as the freshwater ''Hydra'' are solitary, with the polyp attached directly to the substrate. When these produce buds, ...

and bryozoans. They are sometimes also known as ghost shrimps.

Description

Generalized caprellid (skeleton shrimp) body plan anatomy

Caprellids are easily recognizable from other amphipods because of their slender elongated bodies. Their bodies can be divided into three parts: the

cephalon Cephalon, Inc. was an American biopharmaceutical company co-founded in 1987 by pharmacologist Frank Baldino, Jr., neuroscientist Michael Lewis, and organic chemist James C. Kauer—all three former scientists with the DuPont Company. Baldino ...

(head), the

pereon The decapod (crustaceans such as a crab, lobster, shrimp or prawn) is made up of 20 body segments grouped into two main body parts: the cephalothorax and the pleon (abdomen). Each segment may possess one pair of appendages, although in various g ...

(thorax), and the

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the tors ...

. The pereon comprises most of the length of the body. It is divided into seven segments known as pereonites. The cephalon is usually fused to the first pereonite; while the highly reduced and almost invisible abdomen is attached to the posterior of the seventh pereonite. They possess two pairs of antennae, with the first pair usually longer than the second pair. The cephalon contains

mandibles In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...

maxillae The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The tw ...

, and

maxilliped An appendage (or outgrowth) is an external body part, or natural prolongation, that protrudes from an organism's body. In arthropods, an appendage refers to any of the homologous body parts that may extend from a body segment, including ant ...

s which function as mouthparts. Each pereonite has a pair of appendages known as pereopods. The first two pairs are modified into

raptorial The term ''raptorial'' implies much the same as ''predatory'' but most often refers to modifications of an arthropod's foreleg that make it function for the grasping of prey while it is consumed, where the gripping surfaces are formed from the o ...

appendages known as

gnathopod An appendage (or outgrowth) is an external body part, or natural prolongation, that protrudes from an organism's body. In arthropods, an appendage refers to any of the homologous body parts that may extend from a body segment, including antenn ...

s. These are used for feeding and defense, as well as locomotion. The third and fourth pair of pereopods are usually reduced or absent altogether. In the third and fourth pereonites are two pairs of gills. Sometimes a third pair of gills may also be present on the second pereonite. In mature females, brood pouches formed by extensions of the coxae (oostegites) are present on the third and fourth pereonites. The fifth to seventh pair of pereopods are smaller than the gnathopods and are used for clasping objects the animals anchor themselves upon. Most caprellids are highly

sexually dimorphic Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

, with the males usually being far larger than the females.

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

eelgrass Eelgrass is a common name for several plants and may refer to: * ''Zostera'', marine eelgrass * ''Vallisneria ''Vallisneria'' (named in honor of Antonio Vallisneri) is a genus of freshwater aquatic plant, commonly called eelgrass, tape grass or ...

and

bryozoa Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about long, they have a special feeding structure called a ...

ns. They are typically seen attached to substrate by their grasping

appendage An appendage (or outgrowth) is an external body part, or natural prolongation, that protrudes from an organism's body. In arthropods, an appendage refers to any of the homologous body parts that may extend from a body segment, including ant ...

s called the pereopods. Caprellids are omnivorous, feeding on diatoms, detritus, protozoans, smaller amphipods, and

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. The ...

. Some species are

filter feeder Filter feeders are a sub-group of suspension feeding 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 feedin ...

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 Protozoa (singular: protozoan or protozoon; alternative plural: protozoans) are a group of single-celled eukaryotes, either free-living or parasitic, that feed on organic matter such as other microorganisms or organic tissues and debris. Histor ...

or small worms. Caprellids are typically preyed upon by

surf perch The surfperches are a family of perciform fishes, the Embiotocidae. They are mainly found in northeast Pacific Ocean (as far south as Baja California), but a few species (genera '' Ditrema'' and '' Neoditrema'') are found in the northwest Pacifi ...

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 ...

nudibranch Nudibranchs () are a group of soft-bodied marine gastropod molluscs which shed their shells after their larval stage. They are noted for their often extraordinary colours and striking forms, and they have been given colourful nicknames to mat ...

s such as the lion nudibranch '' Melibe leonina'' and brooding anemones ('' Epiactis prolifera''). Since they often inhabit eelgrass beds with sessile jellyfish, (''

Haliclystus ''Haliclystus'' is a genus of stalked jellyfish that contains 11 species and one nomen nudum (''Haliclystus sanjuanensis''). It is the largest genus in the order Stauromedusae. Members of this genus are found in the Pacific, Atlantic, Indian, A ...

'' and '' Thaumatoscyphus''), the caprellids frequently become jellyfish food. Caprellids are not normally considered a main source of food for fish, but when

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. It is the sole member of its genus. The shiner perch is also known as sev ...

(''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 molt in order to grow. After mating the female will brood the fertilized eggs within her brood pouch. 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.

Taxonomy

Caprellidae is classified under the

superfamily SUPERFAMILY is a database and search platform of structural and functional annotation for all proteins and genomes. It classifies amino acid sequences into known structural domains, especially into SCOP superfamilies. Domains are functional, str ...

Caprelloidea Caprelloidea is a superfamily of marine crustaceans in the order Amphipoda. It includes "untypical" forms of amphipods, such as the skeleton shrimps (Caprellidae) and whale lice (Cyamidae). The group was formerly treated as one of the four amp ...

which belongs to the

infraorder Order ( la, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between family and class. In biological classification, the order is a taxonomic rank used in the classification of organisms and ...

Caprellida Caprellidira is a parvorder of marine crustaceans of the infraorder Corophiida. The group includes skeleton shrimps (Caprellidae) and whale lice (Cyamidae). Fifteen families are currently recognised in the group. They are grouped into seven supe ...

of the suborder

Corophiidea Corophiida is an infraorder of amphipods that contains the two parvorders Caprellidira (skeleton shrimp and whale lice) and Corophiidira. In 2003-2013 this group was treated as a suborder, Corophiidea, which in turn had been re-established t ...

. Caprellidae contains 1345 genera in three subfamilies. Caprellinae *'' Abyssicaprella'' McCain, 1966 *'' Aciconula'' Mayer, 1903 *'' Aeginella'' Boeck, 1861 *'' Aeginellopsis'' Arimoto, 1970 *'' Aeginina'' Norman, 1905 *''

Caprella ''Caprella'' is a large genus of skeleton shrimps belonging to the subfamily Caprellinae of the family Caprellidae. It includes approximately 170 species. The genus was first established by Jean-Baptiste Lamarck in his great work ''Système d ...

'' Lamarck, 1801 *'' Caprellaporema'' Guerra-García, 2003 *'' Cubadeutella'' Ortiz ''et al.'', 2009 *'' Deutella'' Mayer, 1890 *'' Eupariambus'' K. H. Barnard, 1957 *'' Hemiaegina'' Mayer, 1890 *'' Heterocaprella'' Arimoto, 1976 *'' Liriopes'' Arimoto, 1978 *'' Liropropus'' Laubitz, 1995 *'' Liropus'' Mayer, 1890 *'' Mayerella'' Huntsman, 1915 *'' Metacaprella'' Mayer, 1903 *'' Metaprotella'' Mayer, 1890 *'' Monoliropus'' Mayer, 1903 *'' Noculacia'' Mayer, 1903 *'' Orthoprotella'' Mayer, 1903 *'' Paracaprella'' Mayer, 1890 *'' Paradeutella'' Mayer, 1890 *'' Paradicaprella'' Hirayama, 1990 *'' Paraprotella'' Mayer, 1903 *''

Pariambus ''Pariambus'' is a genus of amphipod crustaceans comprising the two species ''Pariambus typicus ''Pariambus typicus'' is a species of amphipod crustacean. It is found in the Atlantic Ocean from northern Norway south to the Cape Verde Islan ...

'' Stebbing, 1888 *'' Parvipalpina'' Stephensen, 1944 *'' Parvipalpus'' Mayer, 1890 *'' Pedoculina'' Carausu, 1941 *'' Pedonculocaprella'' Kaim-Malka, 1983 *'' Pedotrina'' Arimoto, 1978 *'' Postoparacaprella'' Arimoto, 1981 *'' Premohemiaegina'' Arimoto, 1978 *'' Pretritella'' Arimoto, 1980 *'' Proaeginina'' Stephensen, 1940 *'' Proliropus'' Mayer, 1903 *'' Propodalirius'' Mayer, 1903 *'' Protella'' Dana, 1853 *'' Protellina'' Stephensen, 1944 *'' Protellopsis'' Stebbing, 1888 *'' Protoaeginella'' Laubitz & Mills, 1972 *'' Prototritella'' Arimoto, 1977 *'' Pseudaeginella'' Mayer, 1890 *'' Pseudolirius'' Mayer, 1890 *'' Pseudoliropus'' Laubitz, 1970 *'' Pseudoprotella'' Mayer, 1890 *'' Tanzacaprella'' Guerra-García, 2001 *''

Thorina ''Thorina'' is a genus of amphipod crustaceans comprising the two species '' Thorina spinosa'' and '' Thorina elongata''. They are deep-sea species, found at depths of and , respectively, in the North Atlantic Ocean and Arctic Ocean Th ...

'' Stephensen, 1944 *'' Triantella'' Mayer, 1903 *'' Triliropus'' Mayer, 1903 *'' Triperopus'' Mayer, 1903 *'' Triprotella'' Arimoto, 1970 *'' Tritella'' Mayer, 1890 *'' Tropicaprella'' Guerra-García & Takeuchi, 2003 *'' Verrucaprella'' Laubitz, 1995 Paracercopinae *''

Cercops Cercops ( grc, Κέρκωψ) was one of the oldest Orphic poets. He was called a Pythagorean by Clement of Alexandria, which might have meant a Neopythagorean.Clement of Alexandria, ''Stromata'', i. Cicero, was said by Epigenes of Alexandria to ...

'' Krøyer, 1843 *'' Paracercops'' Vassilenko, 1972 *'' Pseudocercops'' Vassilenko, 1972 Phtisicinae *'' Aeginoides'' Schellenberg, 1926 *'' Caprellina'' Thomson, 1879 *''

Caprellinoides ''Caprellinoides'' is a genus of amphipods (commonly known as ''skeleton shrimps'') in the family Caprellidae Caprellidae is a family of amphipods commonly known as skeleton shrimps. Their common name denotes the threadlike slender body which ...

'' Stebbing, 1888 *'' Chaka'' Griffiths, 1974 *'' Dodecas'' Stebbing, 1883 *'' Dodecasella'' K. H. Barnard, 1931 *'' Hemiproto'' McCain, 1968 *'' Hircella'' Mayer, 1882 *'' Jigurru'' Guerra-García, 2006 *'' Liriarchus'' Mayer, 1912 *'' Mayericaprella'' Guerra-García, 2006 *'' Metaproto'' Mayer, 1903 *'' Paedaridium'' Mayer, 1903 *''

Paraproto ''Paraproto'' is a genus of marine amphipods in the family, Caprellidae, and was first described in 1903 by Paul Mayer (zoologist), Paul Mayer. The type species is ''Paraproto condylata''. Species of this genus are found at depths of about 200 m ...

'' Mayer, 1903 *'' Perotripus'' Dougherty & Steinberg, 1953 *'' Phtisica'' Slabber, 1769 *'' Prellicana'' Mayer, 1903 *'' Protogeton'' Mayer, 1903 *'' Protomima'' Mayer, 1903 *'' Protoplesius'' Mayer, 1903 *'' Pseudocaprellina'' Sundara Raj, 1927 *'' Pseudododecas'' McCain & Gray, 1971 *'' Pseudoprellicana'' Guerra-García, 2006 *'' Pseudoproto'' Mayer, 1903 *'' Pseudoprotomima'' McCain, 1969 *'' Quadrisegmentum'' Hirayama, 1988 *'' Semidodecas'' Laubitz, 1995 *'' Symmetrella'' Laubitz, 1995

References

External links

* *
Some information on ''Caprella bathytatos''
{{Taxonbar, from=Q2937563 Corophiidea Crustacean families