Arthropods, ACA-SCA

Arthropoda is the largest phylum in the animal kingdom; about 84 percent of all known species of animals fall into this category. Lobsters, crabs, spiders, mites, insects, centipedes, and millipedes are all arthropods.
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Arthropods Encyclopedia Articles By Title

acarid
acarid, (subclass Acari or Acarida or Acarina), any member of the subgroup of the arthropod class Arachnida that......
Agnostus
Agnostus, genus of trilobites (an extinct group of aquatic arthropods) found as fossils in rocks of Early Cambrian......
Ameura
Ameura, genus of trilobites (extinct arthropods) found as fossils in North America rocks dating from the Late Carboniferous......
amphipod
amphipod, any member of the invertebrate order Amphipoda (class Crustacea) inhabiting all parts of the sea, lakes,......
arachnid
arachnid, (class Arachnida), any member of the arthropod group that includes spiders, daddy longlegs, scorpions,......
Arthropleura
Arthropleura, genus of exceptionally large extinct millipede-like arthropods that thrived from the Viséan Age of......
Bagheera kiplingi
Bagheera kiplingi, species of jumping spider (family Salticidae) noted for its largely plant-based diet. The herbivorous......
barnacle
barnacle, any of more than 1,000 predominantly marine crustaceans of the subclass Cirripedia highly modified for......
Bathyuriscus
Bathyuriscus, genus of trilobites (extinct arthropods) that provide a useful index fossil for the Middle Cambrian......
black widow
black widow, (genus Latrodectus), any of about 30 species of black spiders distinguished by an hourglass-shaped......
blue crab
blue crab, (genus Callinectes), any of a genus of crustaceans of the order Decapoda (phylum Arthropoda), particularly......
book lung
book lung, form of respiratory organ found in certain air-breathing arachnid arthropods (scorpions and some spiders).......
branchiopod
branchiopod, any of the roughly 800 species of the class Branchiopoda (subphylum Crustacea, phylum Arthropoda).......
brine shrimp
brine shrimp, (genus Artemia), any of several small crustaceans of the order Anostraca (class Branchiopoda) inhabiting......
brown recluse
brown recluse, (Loxosceles reclusa), venomous light tan or yellow spider most common in the western and southern......
Bumastus
Bumastus, genus of trilobites (extinct arthropods) found in Europe and North America as fossils in rocks of Ordovician......
Calymene
Calymene, genus of trilobites (extinct arthropods) dating from the Ordovician Period (505 to 438 million years......
Cedaria
Cedaria, genus of trilobites (extinct arthropods) that is a useful index fossil for Cambrian rocks and time (about......
centipede
centipede, (class Chilopoda), any of various long, flattened, many-segmented predaceous arthropods. Each segment......
Ceraurus
Ceraurus, genus of trilobites (extinct arthropods) found as fossils in rocks of Ordovician period (505 to 438 million......
chigger
chigger, (suborder Prostigmata), the larva of any of approximately 10,000 species of mites in the invertebrate......
cirripede
cirripede, any of the marine crustaceans of the infraclass Cirripedia (subphylum Crustacea). The best known are......
clam shrimp
clam shrimp, any member of the crustacean order Conchostraca (subclass Branchiopoda), a group of about 200 species......
coconut crab
coconut crab, (Birgus latro), large nocturnal land crab of the southwest Pacific and Indian oceans. It is closely......
comb-footed spider
comb-footed spider, any member of the spider family Theridiidae (order Araneida). The more than 1,000 species of......
copepod
copepod, (subclass Copepoda), any member of the widely distributed crustacean subclass Copepoda. Copepods are of......
crab
crab, any short-tailed member of the crustacean order Decapoda (phylum Arthropoda)—especially the brachyurans (infraorder......
crab spider
crab spider, (family Thomisidae), family of spiders (order Araneida) that are crablike in shape and, like many......
crayfish
crayfish, any of numerous crustaceans (order Decapoda, phylum Arthropoda) constituting the families Astacidae (Northern......
Crepicephalus
Crepicephalus, genus of trilobites (extinct arthropods) useful as an index fossil for Upper Cambrian rocks in North......
crustacean
crustacean, any member of the subphylum Crustacea (phylum Arthropoda), a group of invertebrate animals consisting......
crustacean louse
crustacean louse, any of various small aquatic invertebrates of the subphylum Crustacea (phylum Arthropoda) that......
Cryptolithus
Cryptolithus, genus of trilobites (extinct arthropods) found as fossils in Europe and North America in the Ordovician......
daddy longlegs
daddy longlegs, (order Opiliones), any of more than 6,000 species of arachnids (class Arachnida) that are known......
Daphnia
Daphnia, well-known water flea (q.v.)...
decapod
decapod, (order Decapoda), any of more than 8,000 species of crustaceans (phylum Arthropoda) that include shrimp,......
Deiphon
Deiphon, genus of trilobites (extinct arthropods) easily recognized in fossil form in Silurian rocks in North America......
Dikelocephalus
Dikelocephalus, genus of trilobites (extinct arthropods) that is a useful guide fossil for the Late Cambrian rocks......
dipluran
dipluran, (order Diplura), any of a group of about 800 species of small primitive wingless insects, considered......
Dungeness crab
Dungeness crab, (Cancer magister), edible crab (order Decapoda of the class Crustacea), occurring along the Pacific......
fairy shrimp
fairy shrimp, any of the crustaceans of the order Anostraca, so called because of their graceful movements and......
false scorpion
false scorpion, any of the 1,700 species of the order Pseudoscorpiones (sometimes Chelonethida) of the arthropod......
fiddler crab
fiddler crab, any of the approximately 65 species of the genus Uca (order Decapoda of the subphylum Crustacea).......
fish louse
fish louse, any member of the crustacean subclass Branchiura, a group of parasites of migratory marine and freshwater......
funnel weaver
funnel weaver, any of certain members of the spider family Agelenidae (order Araneida). Agelenids are notable for......
funnel-web spider
funnel-web spider, (family Dipluridae), member of a family of spiders in the order Araneida that are named for......
gammarid
gammarid, any member of the family Gammaridae, the largest of 80 or so families that make up the crustacean order......
garden spider
garden spider, (Araneus diadematus), a member of the orb weaver family Araneidae (order Araneida) characterized......
ghost crab
ghost crab, (genus Ocypode), any of approximately 20 species of shore crabs (order Decapoda of the class Crustacea).......
giant crab
giant crab, (Macrocheira kaempferi), species of spider crab (q.v.) native to Pacific waters near Japan. It occurs......
giant water scorpion
giant water scorpion, any member of the extinct subclass Eurypterida of the arthropod group Merostomata, a lineage......
Greenops
Greenops, genus of trilobites (extinct arthropods) found as fossils in Middle and Upper Devonian deposits (the......
gribble
gribble, any of the approximately 20 species of wood-boring, marine crustaceans constituting the genus Limnoria,......
hermit crab
hermit crab, any crab of the families Paguridae and Coenobitidae (order Decapoda of the class Crustacea). These......
hooded shrimp
hooded shrimp, any member of the order Cumacea (superorder Peracarida), a group of small, predominantly marine......
horseshoe crab
horseshoe crab, (order Xiphosura), common name of four species of marine arthropods (class Merostomata, subphylum......
horseshoe shrimp
horseshoe shrimp, any member of the marine crustacean subclass Cephalocarida (class Crustacea), named because of......
isopod
isopod, any member of the order Isopoda (class Crustacea), a group of diverse, widely occurring forms including......
Isotelus
Isotelus, genus of trilobites (extinct arthropods) restricted to Europe and North America during the Ordovician......
Jonah crab
Jonah crab, North American crab species (Cancer borealis) closely related to the Dungeness crab...
joro spider
joro spider, (Trichonephila clavata), large and visually striking orb weaver spider. Native to Asia, including......
jumping spider
jumping spider, (family Salticidae), any of more than 5,000 species of spiders (order Araneida) known for their......
kelp crab
kelp crab, Pacific species of spider crab...
king crab
king crab, (Paralithodes camtschaticus), marine crustacean of the order Decapoda, class Malacostraca. This edible......
krill
krill, any member of the crustacean order Euphausiacea or of the genus Euphausia within that suborder. Euphausiids......
land crab
land crab, any crab of the family Gecarcinidae (order Decapoda of the class Crustacea), typically terrestrial,......
lobster
lobster, any of numerous marine crustaceans (phylum Arthropoda, order Decapoda) constituting the families Homaridae......
lynx spider
lynx spider, (family Oxyopidae), any of several groups of active spiders (order Araneida) that do not build a nest......
malacostracan
malacostracan, any member of the more than 29,000 species of the class Malacostraca (subphylum Crustacea, phylum......
mantis shrimp
mantis shrimp, any member of the marine crustacean order Stomatopoda, especially members of the genus Squilla.......
millipede
millipede, (class Diplopoda), any member of the arthropod class Diplopoda, distributed worldwide and commonly grouped......
mite
mite, any of numerous species of tiny arthropods, members of the mite and tick subclass Acari (class Arachnida),......
mole crab
mole crab, (Emerita, or Hippa, talpoida), crab of the Atlantic beaches from New England to Mexico. It is so named......
mussel shrimp
mussel shrimp, any of a widely distributed group of crustaceans belonging to the subclass Ostracoda (class Crustacea)......
mustache shrimp
mustache shrimp, any member of the crustacean subclass Mystacocarida, a small group of primitive, free-living marine......
myriapod
myriapod, any member of several closely related groups of the invertebrate phylum Arthropoda, including the extinct......
nursery-web spider
nursery-web spider, (family Pisauridae), any member of a family of spiders (order Araneida) noted for the female......
ogre-faced spider
ogre-faced spider, any member of the family Dinopidae (or Deinopidae; order Araneida). One pair of eyes is unusually......
Olenellus
Olenellus, genus of trilobites (extinct arthropods) common in but restricted to Early Cambrian rocks (542 million......
opossum shrimp
opossum shrimp, any member of the crustacean order Mysidacea. Most of the nearly 1,000 known species live in the......
orb weaver
orb weaver, any spider of the family Araneidae (Argiopidae or Epeiridae) of the order Araneida, a large and widely......
Paradoxides
Paradoxides, genus of trilobites (an extinct group of arthropods) found as fossils in Middle Cambrian rocks of......
pauropod
pauropod, any member of the class Pauropoda (phylum Arthropoda), a group of small, terrestrial invertebrates that......
pea crab
pea crab, any member of a genus (Pinnotheres) of crabs (order Decapoda) living in the mantle cavity of certain......
pentastomid
pentastomid, any of about 100 species of tiny parasites belonging to the Pentastomida, now generally considered......
Phacops
Phacops, genus of trilobites (an extinct group of aquatic arthropods) found as fossils in Silurian and Devonian......
Phillipsia
Phillipsia, genus of trilobites (an extinct group of aquatic arthropods) uncommonly found as fossils in Carboniferous......
pill bug
pill bug, any of the terrestrial crustaceans of the families Armadillididae and Armadillidae (order Isopoda). When......
pirate spider
pirate spider, any member of the family Mimetidae (order Araneida), noted for its habit of eating other spiders.......
prawn
prawn, any of certain crustaceans of the shrimp suborder Natantia. See...
proturan
proturan, any of a group of about 800 species of minute (0.5 to 2 mm [0.02 to 0.08 inch]), pale, wingless, blind,......
ray spider
ray spider, any spider of the family Theridiosomatidae (order Araneida), known for their conelike webs. Most ray......
red crab
red crab, Pacific crab species closely related to the Dungeness crab...
red spider
red spider, any of the plant-feeding mites of the family Tetranychidae (subclass Acari). Red spiders are a common......
redback
redback, (Latrodectus hasselti), species of comb-footed spider (family Theridiidae) that is native to Australia,......
sac spider
sac spider, (family Clubionidae), any member of a relatively common, widespread family of spiders (order Araneida)......
sand flea
sand flea, any of more than 60 terrestrial crustaceans of the family Talitridae (order Amphipoda) that are notable......
scampi
scampi, (Nephrops norvegicus), edible lobster of the order Decapoda (class Crustacea). It is widespread in the......

Arthropods Encyclopedia Articles By Title