Ptocasius is a genus of Asian jumping spiders that was first described by Eugène Louis Simon in 1885.
The genus name derives from the Greek word (ptōchas), meaning "fugitive".
Description According to Simon's original 1885 description, Ptocasius is similar to the genus Hasarius but can be distinguished by several morphological characteristics. The cephalothorax is nearly identical to Hasarius but the eye area above is slightly longer, being barely one-quarter wider than long and either parallel or slightly wider posteriorly. Both anterior eye rows are convex. The eyes resemble those of Hasarius, but the posterior eyes of the second series are positioned wider apart from the posterior eyes than from the more distant anterior eyes.
The labial part is much more attenuated than in Hasarius. The chelicerae have an inferior margin furnished with two geminated teeth of very unequal size, with the second tooth being much smaller than the first. In males, the maxillae have an external posterior angular denticulation. The legs are similar to those of Hasarius, but the tibiae and metatarsi of legs I and II bear lateral spines on both sides, while tibiae I and II lack dorsal spines. Legs III and IV have a dorsal spine positioned in a smaller basin. The integument is clothed with simple hairs that are not squamiform.
Simon also noted that Ptocasius is closely related to the genus Cytaea but differs in having a shorter and more elevated cephalothorax, chelicerae with a superior margin provided with two teeth as in Hasarius (while Cytaea has four small teeth), two very unequal teeth on the inferior margin, and integuments furnished with simple pubescence rather than the squamous pubescence found in Cytaea.
Species
it contains almost 70 described species, found only in Asia:
Ptocasius angulatus Yang & Peng, 2023 – China Ptocasius badongensis (Song & Chai, 1992) – China Ptocasius bhutanicus (Żabka, 1981) – Bhutan Ptocasius bulbosus (Peng, Tang & Li, 2008) – China Ptocasius cambridgei (Żabka, 1981) – Bhutan Ptocasius circulus Yang & Peng, 2023 – China Ptocasius danzhu Yang & Peng, 2023 – China Ptocasius davidi Yang & Peng, 2023 – China Ptocasius dian C. Wang, Mi & Peng, 2023 – China Ptocasius falcatus (Zhu, J. X. Zhang, Z. S. Zhang & Chen, 2005) – China Ptocasius filiformus Yang & Peng, 2023 – China Ptocasius foliolatus Yang & Peng, 2023 – China Ptocasius fulvonitens Simon, 1902 – Sri Lanka Ptocasius geminus Yang & Peng, 2023 – China Ptocasius gogonaicus (Żabka, 1981) – Bhutan Ptocasius gratiosus G. W. Peckham & E. G. Peckham, 1907 – Singapore Ptocasius helvetorum (Żabka, 1981) – Bhutan Ptocasius hubeiensis (Li, Wang, Irfan & Peng, 2018) – China Ptocasius hybridus (Żabka, 1981) – Bhutan Ptocasius incognitus (Żabka, 1981) – Bhutan Ptocasius intermedius (Żabka, 1981) – Bhutan Ptocasius jietouensis Yang & Peng, 2023 – China Ptocasius kinhi Żabka, 1985 – China, Vietnam Ptocasius linzhiensis Hu, 2001 – China Ptocasius longapophysis Yang & Peng, 2023 – China Ptocasius longlingensis Yang & Peng, 2023 – China Ptocasius lushiensis (Zhang & Zhu, 2007) – China Ptocasius metzneri Patoleta, Gardzińska & Żabka, 2020 – Thailand Ptocasius montanus (Żabka, 1981) – China, Bhutan Ptocasius montiformis Song, 1991 – China Ptocasius nepalicus (Żabka, 1980) – Nepal, China Ptocasius nobilis (Żabka, 1981) – Bhutan Ptocasius novus (Żabka, 1981) – Bhutan Ptocasius orientalis (Żabka, 1981) – Bhutan Ptocasius originalis (Żabka, 1981) – Myanmar Ptocasius paraweyersi Cao & Li, 2016 – China, Vietnam Ptocasius pilosus (Żabka, 1981) – Bhutan Ptocasius plumipalpis (Thorell, 1895) – Myanmar Ptocasius pseudoflexus (Liu, Yang & Peng, 2016) – China Ptocasius pulchellus (Li, Wang, Irfan & Peng, 2018) – China Ptocasius rectangulus Yang & Peng, 2023 – China Ptocasius robustus Yang & Peng, 2023 – China Ptocasius sakaerat Patoleta, Gardzińska & Żabka, 2020 – Thailand Ptocasius senchalensis (Prószyński, 1992) – India Ptocasius silvaticus (Żabka, 1981) – Bhutan Ptocasius simoni (Żabka, 1981) – Bhutan Ptocasius songi Logunov, 1995 – China Ptocasius stemmleri (Żabka, 1981) – Bhutan Ptocasius strandi (Żabka, 1981) – Bhutan Ptocasius strupifer Simon, 1901 – China, Vietnam Ptocasius subhubeiensis C. Wang, Mi & Peng, 2023 – China Ptocasius supinus (Żabka, 1981) – Bhutan Ptocasius tenellus (Żabka, 1981) – Bhutan Ptocasius tengchongensis Yang & Peng, 2023 – China Ptocasius tenzingi (Żabka, 1980) – Nepal Ptocasius thakkholaicus (Żabka, 1980) – Nepal, China Ptocasius thimphuicus (Żabka, 1981) – Bhutan Ptocasius umbellulatus Yang & Peng, 2023 – China Ptocasius urbanii (Żabka, 1981) – Bhutan, China Ptocasius variegatus Logunov, 1995 – Kazakhstan Ptocasius versicolor (Żabka, 1981) – Bhutan Ptocasius vittatus Song, 1991 – China Ptocasius wangdicus (Żabka, 1981) – Bhutan Ptocasius weyersi Simon, 1885 – Vietnam, Indonesia (Sumatra) Ptocasius wuermli (Żabka, 1981) – Bhutan, China Ptocasius zabkai Yang & Peng, 2023 – China Ptocasius zonatus Yang & Peng, 2023 – China
References