''Chelifer cancroides'', the house pseudoscorpion, is a species of

pseudoscorpion Pseudoscorpions, also known as false scorpions or book scorpions, are small, scorpion-like arachnids belonging to the order Pseudoscorpiones, also known as Pseudoscorpionida or Chelonethida. Pseudoscorpions are generally beneficial to humans sin ...

. It is

cosmopolitan Cosmopolitan may refer to: Food and drink * Cosmopolitan (cocktail), also known as a "Cosmo" History * Rootless cosmopolitan, a Soviet derogatory epithet during Joseph Stalin's anti-Semitic campaign of 1949–1953 Hotels and resorts * Cosmopoli ...

, synanthropic and harmless to humans.

Subspecies

There are two

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

: * '' Chelifer cancroides cancroides'' ( Linnaeus,

1758 Events January–March * January 1 – Swedish biologist Carl Linnaeus (Carl von Linné) publishes in Stockholm the first volume (''Animalia'') of the 10th edition of Systema Naturae, 10th edition of ''Systema Naturae'', the sta ...

) * '' Chelifer cancroides orientalis'' (Morikawa, 1954)

Description

''Chelifer cancroides'' measure in length. The pedipalps are very long, measuring when extended. The body is teardrop-shaped and has a rich mahogany color. 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 torso. ...

has 12 segments, only 10 of which are easily visible. The

cephalothorax The cephalothorax, also called prosoma in some groups, is a tagma of various arthropods, comprising the head and the thorax fused together, as distinct from the abdomen behind. (The terms ''prosoma'' and ''opisthosoma'' are equivalent to ''cepha ...

has one pair of eyes. This species can be distinguished from other

Cheliferidae Cheliferidae is a family of pseudoscorpions in the order Pseudoscorpiones Pseudoscorpions, also known as false scorpions or book scorpions, are small, scorpion-like arachnids belonging to the order Pseudoscorpiones, also known as Pseudoscorpion ...

by a number of features. The

carapace A carapace is a Dorsum (biology), dorsal (upper) section of the exoskeleton or shell in a number of animal groups, including arthropods, such as crustaceans and arachnids, as well as vertebrates, such as turtles and tortoises. In turtles and tor ...

has large setose tubercles. In males, the carapace and tergites I-VII or I-VIII have distinct lateral keels. The cheliceral hand has 4 setae, lacking seta ''sbs''. The tarsal claws of adults have a lateroventral process, except for those on the first leg pair of adult males. Additionally, the suberminal tarsal setae are denticulate. In males, coxa IV is strongly arcuate, has a large lateral process, and has a coxal sac lacking a differentiated atrium. The male genitalia have rams horn organs and an anteriorly invaginated lateral rod forming a median depression, in which lies a sclerotic rod. The female genitalia have paired spermathecae and paired median cribriform plates.

Diet

''Chelifer cancroides'' feeds on small arthropods such as psocids, fruit flies and '' Varroa'' mites.

Reproduction

Males maintain small mating territories, few centimeters in size. When a female enters the territory, the male initiates a mating dance and eventually deposits a

spermatophore A spermatophore or sperm ampulla is a capsule or mass containing spermatozoa created by males of various animal species, especially salamanders and arthropods, and transferred in entirety to the female's ovipore during reproduction. Spermatophores ...

, which is then picked up by the females. Fecundity is 20–40 eggs. The development from egg stage into maturity takes 10 to 24 months and involves three molts; molting may involve building a silk nest. They usually live three or four years.

Distribution

''Chelifer cancroides'' has been observed in North America, Europe, Africa, and Australia.

Habitat

''Chelifer cancroides'' has been found under bark of trees, in caves, in bird nests and bee nests, and riding on bats, flies and hymenopterans. It also occurs in human structures such as houses, stables, barns, chicken coops and bee hives.

Venom

Like some other pseudoscorpions, ''C. cancroides'' has venomous pedipalps used for subduing prey. This venom contains various

peptides Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A p ...

and is toxic to bacteria (e.g. methicillin resistant ''Staphylococcus aureus''), fungi, arthropods (e.g. aphids and ''Varroa'' mites) and mammalian cells.

References

External links

{{Taxonbar, from=Q937723 Arachnids of North America Cheliferidae Cosmopolitan arthropods Animals described in 1758 Taxa named by Carl Linnaeus