''Harpactea sadistica'' is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

of dysderine

spider Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...

, found only in

Israel Israel (; he, יִשְׂרָאֵל, ; ar, إِسْرَائِيل, ), officially the State of Israel ( he, מְדִינַת יִשְׂרָאֵל, label=none, translit=Medīnat Yīsrāʾēl; ), is a country in Western Asia. It is situated ...

. It was first described in 2008.

Description

Both sexes have the same body characteristics. The length of the pale yellow-brown, smooth carapace ranges from 1.1 to 1.7 mm. The legs are pale yellow, with the first two pairs darker than the other two. The cylindrical, whitish

opisthosoma The opisthosoma is the posterior part of the body in some arthropods, behind the prosoma (cephalothorax). It is a distinctive feature of the subphylum Chelicerata (arachnids, horseshoe crabs and others). Although it is similar in most respects to a ...

is 2.3 mm long in the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

specimen Specimen may refer to: Science and technology * Sample (material), a limited quantity of something which is intended to be similar to and represent a larger amount * Biological specimen or biospecimen, an organic specimen held by a biorepository ...

. The tip of the

embolus An embolus (; plural emboli; from the Greek ἔμβολος "wedge", "plug") is an unattached mass that travels through the bloodstream and is capable of creating blockages. When an embolus occludes a blood vessel, it is called an embolism or emb ...

of the male resembles the tip of a

hypodermic needle A hypodermic needle (from Greek ὑπο- (''hypo-'' = under), and δέρμα (''derma'' = skin)), one of a category of medical tools which enter the skin, called sharps, is a very thin, hollow tube with one sharp tip. It is commonly used w ...

, and the

vulva The vulva (plural: vulvas or vulvae; derived from Latin for wrapper or covering) consists of the external sex organ, female sex organs. The vulva includes the mons pubis (or mons veneris), labia majora, labia minora, clitoris, bulb of vestibu ...

of the female is atrophied.Rezac 2008

Ecology

''Harpactea sadistica'' probably exhibits an annual lifecycle. Eggs are laid from March to April. The species is found in woodlands dominated by ''

Quercus calliprinos ''Quercus calliprinos'' is an oak classified as part of the ''Ilex'' section of the genus growing in the Mediterranean climate zone, mainly on limestone, in mid-elevations, often dominating the flora, alongside terebinths (''Pistacia terebinthu ...

'' and

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accep ...

plantations, and in steppe habitats where ''

Asphodelus ''Asphodelus'' is a genus of mainly perennial flowering plants in the asphodel family Asphodelaceae that was first described by Carl Linnaeus in 1753. The genus was formerly included in the lily family (Liliaceae). The genus is native to tempera ...

'' is predominant.

Traumatic insemination

''Harpactea sadistica'' is the first spider species – and the first member of the entire

subphylum In zoological nomenclature, a subphylum is a taxonomic rank below the rank of phylum. The taxonomic rank of "subdivision (rank), subdivision" in fungi and plant taxonomy is equivalent to "subphylum" in zoological taxonomy. Some plant taxonomists ...

Chelicerata The subphylum Chelicerata (from New Latin, , ) constitutes one of the major subdivisions of the phylum Arthropoda. It contains the sea spiders, horseshoe crabs, and arachnids (including Opiliones, harvestmen, scorpions, spiders, Solifugae, solif ...

– found to use

traumatic insemination Traumatic insemination, also known as hypodermic insemination, is the mating practice in some species of invertebrates in which the male pierces the female's abdomen with his aedeagus and injects his sperm through the wound into her abdominal c ...

. The males have specialized genital structures at the

pedipalp Pedipalps (commonly shortened to palps or palpi) are the second pair of appendages of chelicerates – a group of arthropods including spiders, scorpions, horseshoe crabs, and sea spiders. The pedipalps are lateral to the chelicerae ("jaws") and ...

s that are adapted to grip the female and inject the

sperm Sperm is the male reproductive cell, or gamete, in anisogamous forms of sexual reproduction (forms in which there is a larger, female reproductive cell and a smaller, male one). Animals produce motile sperm with a tail known as a flagellum, whi ...

, using a structure resembling a

. After positioning himself, the male pierces the female on both sides and injects the sperm directly into the

ovaries The ovary is an organ in the female reproductive system that produces an ovum. When released, this travels down the fallopian tube into the uterus, where it may become fertilized by a sperm. There is an ovary () found on each side of the body. T ...

, resulting in about eight holes in two rows. Consistent with the modified mating behavior, the

spermatheca The spermatheca (pronounced plural: spermathecae ), also called receptaculum seminis (plural: receptacula seminis), is an organ of the female reproductive tract in insects, e.g. ants, bees, some molluscs, oligochaeta worms and certain other ...

e of the female, which normally store received sperm, are weakly developed in this species. Whereas in other spiders the eggs are fertilized only when laid, in this special case fertilization takes place at the moment of insemination, and develop as embryos before being laid.Rezac 2009 This behavior seems to have evolved in order to ensure that the mating male is also the one providing the sperm for the progeny. Spermathecae fertilize the eggs with the sperm of the last mating male. With the adaption of traumatic insemination, the male ensures that his sperm will be used, circumventing this mechanism.BBC News April 30, 2009 Like many other spider species, ''H. sadistica'' has elaborated mating rituals preceding the insemination, involving tapping the female, subduing her and wrapping himself around her in order to position himself prior to insemination.

Name

The species name refers to the seemingly sadistic habit of stabbing the body cavity of the female.

Notes

References

* (2008) Description of ''Harpactea sadistica'' n. sp. (Araneae: Dysderidae) — a haplogyne spider with reduced female genitalia. ''Zootaxa'' 1698: 65-68
Abstract
* (2009): The spider ''Harpactea sadistica'': co-evolution of traumatic insemination and complex female genital morphology in spiders. ''Proc Biol Sci.'' — * (2009)

version 9.5. ''American Museum of Natural History''. * BBC News (April 30, 2009)
Spider sex violent but effective
{{Taxonbar, from=Q1315557 Dysderidae Endemic fauna of Israel Spiders of Asia Spiders described in 2008