Phintella parva

Phintella parva (묘향깡충거 미) is a species of jumping spider in the genus Phintella that lives in China, Japan, Korea and Russia. The species was first described by Wanda Wesołowska in 1981 based on a holotype from North Korea. It was originally allocated to the genus Icius with the name Icius parvus but was transferred to its current genus by Jerzy Prószyński in 1983. It was also recognised that other examples of the spider had been previously collected including, at one time, a description published without a species name. The spider is small and yellow, measuring between 3.5 and 4 mm in body length. The spider exhibits sexual dimorphism and the female is slightly larger than the male. The abdomen has a striped pattern and the carapace has circular markings, but the most distinguishing difference between this species and other members of the genus are its copulatory organs, particularly the short curved embolus on the male and long straight insemination ducts in the female.

Taxonomy and etymology
In 1981, the Polish arachnologist Wanda Wesołowska described a new species of jumping spider, a member of the family Salticidae, which she named Icius parvus. It was, one of over 500 species that she identified by over her career. Originally ascribed to the genus Icius, first circumscribed by Eugène Simon in 1876, the species was later transferred to Phintella in 1983 by Jerzy Prószyński. At the same time, the gender of the species name was changed, from parvus to parva.

The genus Phintella was first circumscribed in 1906 by Embrik Strand and W. Bösenberg. There are similarities between spiders within genus Phintella and those in Chira, Chrysilla, Euophrys, Icius, Jotus and Telamonia. Genetic analysis confirms that it is related to the genera Helvetia and Menemerus. In 2015, Wayne Maddison confirmed that it is classified in the tribe Chrysillini, named after the genus Chrysilla. In 2017, the genus was grouped with 32 other genera of jumping spiders under the name Chrysillines in the supergroup Chrysilloida by Prószyński.

Phintella parva is known as 묘향깡충거 미 (Myo-hyang-kkang-chung-geo-mi) in Korea. The species name is the Latin word for small. The genus name derives from the genus Phintia due to the similarities between the two genera. Phintia was itself renamed Phintodes and was subsequently absorbed into the genus Tylogonus.

Description
Phintella parva is a small spider with some sexual dimorphism. The female is larger than the male, with a total length of between 4 and 5 mm. It has a body is divided into two main parts: a cephalothorax and an abdomen. The cephalothorax has a length of between 1.78 and 2.05 mm and a width of between 1.28 and 1.55 mm. The carapace, the hard upper shell of the cephalothorax, is longer than it is wide and shaped like a quadrangle. It is yellow with circular markings to towards the back. The spider's eye field is black. The underside of the carapace, or sternum, has brown sides and a yellow middle. The mouthparts are distinctive. The chelicerae, labium and area around the mouth is yellow with brown lines around the sides.

The abdomen measures between 2.98 and 3.08 mm long and 1.8 and 2.18 mm wide. It is also yellow and has two broad stripes running down it and along the sides. Some spiders have an additional stripe down the middle of the abdomen. Four or five chevrons can often be seen at the very back. There is another black stripe on the underside that stretches from the epigastric furrow at the back to spiracle. The spinnerets are yellow, as are the spider's legs. It has unusual copulatory organs. The epigyne, the external female copulatory organ, is small with minor signs of sclerotization.| It has a pocket towards the very rear, near the epigastric furrow. The copulatory openings lead via relatively long straight insemination ducts to spherical spermathecae, or receptacles.

The male is similar to the female. It is slightly smaller with a total length of between 3.78 and 4.67 mm. The cephalothorax is between 1.73 and 1.9 mm long and between 1.25 and 1.38 mm wide. The carapace has similar colouring, but is less pale. The mouthparts are similar to the female. The abdomen is between 1.83 and 2 mm long and 1.05 and 1.2 mm wide. The legs are similarly yellow, although there are brown patches on their femora. The palpal bulb is slightly smaller than others in the genus, with a shape reminiscent of a bean. It has a short curved embolus emanating from the palpal bulb and a single tibial apophysis, a projection on the pedipalp tibia.

Similar species
Phintella parva is often confused with other species of the genus. Particularly, it closely resembles the related Phintella popovi, differing in the shape of the copulatory organs. The male's curved embolus and straight and tibial apophysis are characteristic and the length of the insemination ducts in the female enables the species to be identified. Cluster analysis confirms that the species is most closely related to the Phintella cavaleriei, and then Phintella bifurcilinea, both of which share similar species distributions.

At the same time as she described Icius parvus, Wesołowska also described two other species, which she identified as being members of the existing species Icius linea or Icius abnomis. She recognised that the samples were similar to those species but that the exact relationship between the different specimens uncertain. In 2000, Dmitri Logunov and Yu Marusik identified that these two examples were actually of this species. The first example in Japan was originally thought to be Phintella mellotei while a male specimen had been misnamed Phintella difficilis by Logunov in 1979. This was rectified in 1992 by Logunov and Wesołowska. All these specimens are now recognised as being members of the species Phintella parva.

Distribution and habitat
Phintella parva lives in China, Japan, Korea and Russia. The holotype for the species was discovered in the valleys around Mount Myohyang, North Korea, by Bohdan Pisarski and Prószyński in 1959. Female specimens were also seen near to the city of Pyongyang and in the South Hamgyong Province. They were not described and named until 1981. Subsequently, examples have been found throughout the country. The first recorded siting in Haeju was in 1987, followed by Chongjin, Hongwon County, Kaesong and Kyongsong County in 1990. The spider was also found in the areas around Mount Kumgang at the same time. South Korea was later added to the species distribution, with examples being identified in Sobaeksan and area around Palgongsan in the North Gyeongsang Province, the first to be found dating from 1964.

Subsequent identifications have shown that the species also lives outside the Korean peninsula. Wesołowska also identified that it had been found in Primorsky Krai, in what is now Russia, and described in 1979, but had not been given a species name. It was later seen that the spider was also to live on Furugelm Island. The first example in China was identified in Shanxi. The species was subsequently found in many other areas of the country, including Beijing, Gansu, Hebei and Henan. Hebei is a particularly rich area for the species. Finds include 19 examples collected from Zhuolu County in 2004 and Yu County in 2006. The spider has also been observed in the Mie Prefecture of Honshu, Japan, which extended its range still further.

The spider seems to thrive in diverse environments, including the environs of Tianchi Mountain, Song County, Luoyang, the city of Linzhou, rural areas in Neixiang County and pine woods of Khabarovsk Krai.