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Species
Araneae
IUCN
NCBI
EOL Text
All spiders are predators. They attack only live Insecta, other Araneae, and other invertebrates. A few very large spider species attack small vertebrates like Squamata, Pimephales notatus, or Anura, but this is rare. Spiders are famous for trapping their prey in webs of sticky silk, but many of them are wandering predators who don't use silk to catch prey.
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | ©1995-2012, The Regents of the University of Michigan and its licensors |
| Source | http://www.biokids.umich.edu/critters/Araneae/ |
Mechanism to seal joint prevents depressurization: spiders
The legs of spiders are protected from depressurization when damaged via a joint sealing mechanism.
"One particular hydraulic device is worth a little more attention here, partly because its existence comes as yet another surprise and partly because it achieves antagonism for contractile muscle in an unusual way. The eight legs of a spider differ little from the six of an insect, but a curious special feature of spider legs has been known for almost a century. While properly equipped with flexor muscles (ones that decrease the angle between one segment and another), they lack the antagonistic extensor muscles (ones that increase that angle toward 180 degrees). Biologists casually assumed that elasticity of the interarticular membranes provided the antagonistic force, not on the face of it an unreasonable idea. But Ellis (1944) remembered that spiders die with legs severely flexed. If elasticity did the extension, they would more likely die with legs extended or at least not so flexed--as do insects. He found that cutting off the tip of a leg prevented re-extenson until the tip was resealed; and he found that mild exsanguination reduced a spider's ability to extend any of its legs. He suggested that extension in spider legs was hydraulic, not muscular or elastic. The idea was confirmed by Parry and Brown (1959), who measured resting pressures of 6.6 kilopascals and transient pressures of up to 60 kilopascals (over half an atmosphere) in spider legs. An isolated leg could lift more weight as the pressure inside it was increased, and the spiders turned out to have a special mechanism to seal off a joint that prevented fatal depressurization when a leg was lost." (Vogel 2003:421)
Learn more about this functional adaptation.
| License | http://creativecommons.org/licenses/by-nc/3.0/ |
| Rights holder/Author | (c) 2008-2009 The Biomimicry Institute |
| Source | http://www.asknature.org/strategy/7c45f8c9f552e8ba03e72dd2bc08fa6d |
Spiders are major predators of insects, including many insects that are pests to humans.
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | ©1995-2012, The Regents of the University of Michigan and its licensors |
| Source | http://www.biokids.umich.edu/critters/Araneae/ |
Barcode of Life Data Systems (BOLD) Stats
Specimen Records:93416
Specimens with Sequences:70176
Specimens with Barcodes:67332
Species:5866
Species With Barcodes:5147
Public Records:65137
Public Species:2922
Public BINs:7360
Spiders often have good camouflage, and many of the wandering hunter species hunt at night when big predators can't see them. Many spiders build a retreat of silk to hide in too. Some are quick runners, and will just run away if they can. These may use their silk as a safety line, jumping off into the air with a silk thread attached so they don't fall.
Known Predators:
- other Araneae
- Hymenoptera
- Formicidae
- praying mantids
- Aves
- small Squamata
- Amphibia
- small mammals especially Soricidae
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | ©1995-2012, The Regents of the University of Michigan and its licensors |
| Source | http://www.biokids.umich.edu/critters/Araneae/ |
In Great Britain and/or Ireland:
Animal / predator / stocks nest with
female of Arachnospila anceps stocks nest with Araneae
Animal / predator / stocks nest with
female of Arachnospila consobrina stocks nest with Araneae
Animal / predator / stocks nest with
female of Arachnospila minutula stocks nest with Araneae
Animal / predator
Araneae is predator of Bombus
Animal / predator / stocks nest with
female of Auplopus carbonarius stocks nest with Araneae
Animal / pathogen
colony of Gibellula anamorph of Gibellula aranearum infects Araneae
Animal / pathogen
colony of Hymenostilbe anamorph of Hymenostilbe arachnophila infects Araneae
Animal / predator
larva of Melanophora roralis is predator of egg cocoon of Araneae
Animal / predator / stocks nest with
female of Miscophus ater stocks nest with Araneae
Animal / predator / stocks nest with
female of Miscophus concolor stocks nest with Araneae
Animal / predator
leaf of Pinguicula vulgaris is predator of adult of Araneae
Animal / parasitoid
gregarious, mycelioid perithecium of Torrubiella albolanata is parasitoid of Araneae
Animal / parasitoid
scattered, sparsely subiculate perithecium of Torrubiella aranicida is parasitoid of body & legs of Araneae
Animal / predator / stocks nest with
female of Trypoxylon attenuatum stocks nest with Araneae
Animal / predator / stocks nest with
female of Trypoxylon clavicerum stocks nest with Araneae
Animal / predator / stocks nest with
female of Trypoxylon figulus s.s. stocks nest with Araneae
Animal / predator / stocks nest with
female of Trypoxylon medium stocks nest with Araneae
Animal / predator / stocks nest with
female of Trypoxylon minus stocks nest with Araneae
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | BioImages, BioImages - the Virtual Fieldguide (UK) |
| Source | http://www.bioimages.org.uk/html/Araneae.htm |
Spiders scare a lot of people (usually this is unnecessary). A few spider species have venom that is dangerous to people, but spider bites are actually pretty rare. They get blamed for a lot of skin injuries that are not actually spider bites. Most spiders have such small weak fangs that they couldn't break a person's skin, even if they wanted to.
Negative Impacts: injures humans (bites or stings)
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | ©1995-2012, The Regents of the University of Michigan and its licensors |
| Source | http://www.biokids.umich.edu/critters/Araneae/ |
Araneae is prey of:
Lagopus
Plectrophenax nivalis
Calidris maritima
Anura
Agelaius phoeniceus
Quiscalus quiscula
Melospiza melodia
Dendroica petechia
Geothlypis trichas
Empidonax minimus
Vireo gilvus
Icterus galbula
Pheucticus ludovicianus
Catharus fuscescens
Poecile atricapillus
Rana pipiens
Paridae
parasites
Aves
Lepidosauria
Hirundinidae
Scolopacidae
Talpinae
Aporosaura
Typhlosaurus
Red racer
Pituophis
Crotalus
Urocyon cinereoargenteus
Mephitinae
Onychomys
Geococcyx velox
Phasianidae
Timaliidae
Pavo
Serpentes
Varanidae
Canis aureus
Erinaceus europaeus
bultul
Laniidae
Saxicoloides fulicata
Vulpes vulpes
Passeriformes
Calamospiza melanocorys
Peromyscus maniculatus
Orthoptera
Buteo jamaicensis
Saurothera vieilloti
Amphisbaena caeca
Herpestes auropunctatus
Eleutherodactylus coqui
Eleutherodactylus richmondi
Eleutherodactylus portoricensis
Eleutherodactylus wightmanae
Eleutherodactylus eneidae
Melanerpes portoricensis
Todus mexicanus
Mimocichla plumbea
Margarops fuscatus
Anolis cuvieri
Anolis evermanni
Anolis stratulus
Anolis gundlachi
Leptodactylus albilabris
Vireo latimeri
Nesospingus speculiferus
Icterus dominicensis
Mimetes portoricensis
Vireo altiloquus
Seiurus aurocapillus
Seiurus motacilla
Sphaerodactylus klauberi
Sphaerodactylus macrolepis
Diploglossus pleei
Geophilomorpha
Chlorostilbon maugeus
Anthracothorax viridis
Mniotilta varia
Parula americana
Dendroica caerulescens
Dendroica discolor
Setophaga ruticilla
Coereba flaveola
Loxigilla portoricensis
Pseudoscorpionida
Tyrannus dominicensis
Elaenia
Tiaris
Trochilidae
Anolis gingivinus
Anolis pogus
Chilopoda
Based on studies in:
Norway: Spitsbergen (Coastal)
Canada: Manitoba (Grassland)
Russia (Agricultural)
Malaysia (Swamp)
England: Oxfordshire, Wytham Wood (Forest)
Namibia, Namib Desert (Desert or dune)
USA: Alaska (Tundra)
USA: Arizona, Sonora Desert (Desert or dune)
India, Rajasthan Desert (Desert or dune)
USA: Massachusetts, Cape Ann (Marine)
USA: California, Cabrillo Point (Grassland)
Puerto Rico, El Verde (Rainforest)
This list may not be complete but is based on published studies.
| License | http://creativecommons.org/licenses/by/3.0/ |
| Rights holder/Author | Cynthia Sims Parr, Joel Sachs, SPIRE |
| Source | http://spire.umbc.edu/fwc/ |
Spiders eat a lot of insects that are agricultural pests and eat our food.
Positive Impacts: controls pest population
| License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
| Rights holder/Author | ©1995-2012, The Regents of the University of Michigan and its licensors |
| Source | http://www.biokids.umich.edu/critters/Araneae/ |