Description of a new species of Thelcticopis Karsch (Araneae, Sparassidae) from Guangxi Province, China

Abstract Background Due to its special ways of hiding and lifestyle, Thelcticopis is a type of spider that is very difficult to collect. In 2018, we collected two huntsman spiders in Guangxi. After comparison with other Thelcticopis species, such as anterior median eye larger than other eyes, they were found to belong to the genus of Thelcticopis. New information Currently, four Thelcticopis species are reported from China, T. severa (L. Koch, 1875), T. zhengi Liu, Li & Jäger, 2010, T. dahanensis Zhu & Zhong, 2020 and T. unciformis Zhu & Zhong, 2020. They are mainly distributed in the tropical or subtropical areas of China (Fujian, Guangdong, Guangxi, Hainan, Hongkong, Hunan, Taiwan, Yunnan and Zhejiang). In this paper, we diagnose and describe a new species, Thelcticopis pinmini sp. nov., which was collected from Guangxi Province, China.


Introduction
belongs to the subfamliy Sparianthinae Simon, 1897 of the family Sparassidae Bertkau, 1872(Bertkau 1872, Karsch 1884, Simon 1897. Spiders of Thelcticopis are usually medium to large-sized, found on tree bark or inhabiting foliage and leaf litter. They are distributed in Latin and South America, Africa, Asia and Australia (Zhu et al. 2020). Due to their nocturnal lifestyle and quick ways of hiding, matched pairs of species of Thelcticopis are hard to collect in the field. To date, currently 50 species have been recorded worldwide, amongst which 37 species are based on a single sex (World Spider Catalog 2021). While examining specimens from Guangxi Province of China, one new species of the genus Thelcticopis was identified and is described here.

Materials and methods
Specimens were examined and measured with a Leica M205C stereomicroscope. Positions of the tegular appendages are given according to clock positions, based on the left palp in ventral view. Male palps were examined after dissection and removal from the spiders' bodies, the epigynes were examined and illustrated after dissection. Female copulatory organs were cleared in proteinase K at 56°C to dissolve non-chitinous tissues. All photographs were captured with an Olympus C7070 wide zoom digital camera (7.1 megapixels), mounted on an Olympus SZX12 dissecting microscope and assembled using Helicon Focus 7.0 image stacking software. Photographic images were then edited, using Adobe Photoshop CC 2015. Most of the hairs and macrosetae were generally not identified in the palp and epigyne drawings. All specimens are deposited in the Centre for Behavioural Ecology and Evolution, College of Life Sciences, Hubei University, Wuhan, China (CBEE).
Copulatory organs as in diagnosis. Epigynal field wider than long with one slit sensillum on each side of the epigynal field. Median septum medially about 1/2 of epigynal's width, with two humps on the posterior part. Posterior margin with two hooks, each pointing medially. Both sides of internal duct sustem separated. Fertilisation ducts arising posterior-laterally (Fig. 1D-E and Fig. 3D-E).
Colouration in ethanol: as in male, but dorsal opisthosoma yellowish-brown with wide dark spots ( Fig. 4C-D).

Diagnosis
Male of this species can be distinguished from the remaining species of the genus by its palps with embolic apophysis and embolus distally with an obvious crack ( Fig. 1A-C,   Fig. 2A and Fig. 3A-B). Female resembles Thelcticopis folia Jäger &Praxaysombath, 2009 (see Jäger andPraxaysombath 2009: 48, figs. 106-113) in having a roundish median plate ( Fig. 1D and Fig. 3D) and initial part of internal duct system narrow, leading to a chamber ( Fig. 1E and Fig. 3E), but can be distinguished from the latter by the following characters: 1, median septum rounded in anterior part and two humps on the posterior part (not in T. folia); 2, anterior part of internal duct system touching each other and distinctly narrower than posterior part (separated, the median part narrower than the other parts in T. folia).

Etymology
The specific name is dedicated to Mr Pinmin Li for his kind instructions on our collection of huntsman spiders; name in the genitive case.

Distribution
Known only from the type locality (Fig. 5).