''Thiratoscirtus minimus'' is a species of jumping spider in the genus ''

Thiratoscirtus ''Thiratoscirtus'' is a genus of Salticidae, jumping spiders that was first described by Eugène Simon, Eugène Louis Simon in 1886. Species it contains twenty-six species, found only in Africa, Argentina, and Brazil: *''Thiratoscirtus alveolus' ...

'' that lives in Kenya. The species was first described in 2016 by Angelika Dawidowicz and Wanda Wesołowska. It is a medium-sized spider, with a

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 ...

] and an Opisthosoma, abdomen both typically 1.7 mm in length, although radically different in shape. The spider's

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 ...

is oval and generally brown while its abdomen a narrower greyish-brown ovoid. The area around its eyes is black. It has yellow

legs A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element ...

that are marked with grey rings and have multiple spines. The male has pedipalps that are similar to the related '' Thiratoscirtus gambari'' but has a smaller palpal tibia, which is recalled in the species name, which means "tiny".

Taxonomy

''Thiratoscirtus minimus'' is a species of jumping spider, a member of the family Salticidae, that was first described by the

arachnologists Arachnology is the scientific study of arachnids, which comprise spiders and related invertebrates such as scorpions, pseudoscorpions, and harvestmen. Those who study spiders and other arachnids are arachnologists. More narrowly, the study of sp ...

Angelika Dawidowicz and Wanda Wesołowska in 2016. One of over 500 different species identified by Wesołowska in her career, it is named with a Latin word that means "tiny" and relates to the small size of its papal tibia. They allocated the spider to the genus ''

'', first

circumscribed In geometry, the circumscribed circle or circumcircle of a polygon is a circle that passes through all the vertices of the polygon. The center of this circle is called the circumcenter and its radius is called the circumradius. Not every polyg ...

in 1909 by

Eugène Simon Eugène Louis Simon (; 30 April 1848 – 17 November 1924) was a French naturalist who worked particularly on insects and spiders, but also on birds and plants. He is by far the most prolific spider taxonomist in history, describing over 4, ...

. The genus is very diverse and contains many

monophyletic In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic gro ...

groups. ''Thiratoscirtus'' is a member of the

subtribe Subtribe is a taxonomic category ranking which is below the rank of tribe and above genus. The standard suffix for a subtribe is -ina (in animals) or -inae (in plants Plants are predominantly photosynthetic eukaryotes of the kingdom Plant ...

Thiratoscirtina in the tribe Aelurillini. The genus is closely related to ''

Nimbarus ''Nimbarus'' is a monotypic genus of Guinean jumping spiders containing the single species, ''Nimbarus pratensis''. It was first described by C. Rollard & Wanda Wesołowska in 2002, and is only found in Guinea Guinea ( ),, fuf, 𞤘� ...

''. Wayne Maddison allocated the tribe to the subclade Simonida in the

clade A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, ...

Saltafresia in the clade

Salticoida Salticoida is an unranked clade of the jumping spider family Salticidae. It is the larger and more widespread of the two subdivisions of the "typical" jumping spiders (subfamily Salticinae), occurring effectively world-wide. Its sister clade is ...

. In 2016, Mellissa Bodner and Maddison proposed a

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Thiratoscirtinae for the genus and its related genera. This overlapped with a group of genera named Thiratoscirtines after the genus, created by

Jerzy Prószyński Jerzy Prószyński (born 1935 in Warsaw) is a Polish arachnologist specializing in systematics of jumping spiders (family Salticidae). He is a graduate of the University of Warsaw, a long-term employee of the Siedlce University of Natural Scienc ...

in 2017. Phylogenetic analysis has shown that the genus is related to the genera '' Alfenus'', ''

Bacelarella ''Bacelarella'' is a genus of African Salticidae, jumping spiders that was first described by Lucien Berland & J. Millot in 1941. This genus was named in honour of the Portuguese arachnologist Amélia Bacelar. Species it contains eight species, ...

'', '' Longarenus'' and '' Malloneta''. It is likely to have diverged between 16.3 and 18.7 million years ago.

Description

''Thiratoscirtus minimus'' is a medium-sized spider. The spider's body is divided into two main parts: a round

and a smaller ovoid Opisthosoma, abdomen. The male has a cephalothorax that measures typically in length and in width. The

, the hard upper part of the cephalothorax, is high with a strong slope to the rear. It is generally brown and covered in colourless hair. It is marked with a light streak and has a furrow-like depression in the middle. A black field surrounds the eyes, with a few short brown bristles visible particularly to the front. The sternum, the underside of the cephalothorax, is brownish. Its clypeus is low with long white hairs. Its mouthparts are generally light brown, with paler tips on the labium and

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 t ...

, while chelicerae are brown with two teeth to the front and a single tooth at the back. The spider's abdomen is the same length as the carapace but significantly narrower, being typically wide. It is a generally greyish-brown with a light serrated streak across the middle, and is covered in light hairs that are denser to the front. The underside is yellowish, as are thee spider's spinnerets. Its

are genera;;y yellow with grey rings marking off some the segments. The legs have long white and brown hairs and a multiple brown spines. The pedipalps, sensory organs near the mouth, are light brown and covered in dense light brown hairs. The male copulatory organs include a rounded hairy cymbium that surrounds the smaller irregularly-shaped palpal bulb. A long thin embolus extends from the near the bottom of the bulb and curves around towards th top of the cymbium but finishes in a point before it reaches that point. Its palpal tibia is small and hairy, and has a very small single slightly curved spike, or tibial apophysis. The pedipalp is very similar to the related '' Thiratoscirtus gambari'', but the embolus starts at a different place on the palpal bulb and the tibia is smaller. The female has not been described.

Distribution

''Thiratoscirtus'' spiders generally live in Africa and are particularly common in the forests of Central and West Africa. ''Thiratoscirtus minimus'' is endemic to Kenya. It has only been seen in the Kakamega Forest. The holotype was found living at an altitude of

above sea level Height above mean sea level is a measure of the vertical distance (height, elevation or altitude) of a location in reference to a historic mean sea level taken as a vertical datum. In geodesy, it is formalized as ''orthometric heights''. The comb ...

References

Citations

Bibliography

* * * * * * * {{Taxonbar, from=Q27505186 Endemic fauna of Kenya Salticidae Spiders described in 2016 Spiders of Africa Taxa named by Wanda Wesołowska