Euscorpiops lii sp. nov. and a key of the genus Euscorpiops Vachon, 1980 (Scorpiones, Scorpiopidae) from China

Abstract A new species, Euscorpiops liisp. nov., from Xizang (Tibet) in southwest China is described herein. Adult scorpions in this species are principally characterized by yellow-brown colour, a length of less than 40 mm, 17 trichobothria on the external surface of the pedipalp patella and usually six trichobothria on the ventral surface of the pedipalp patella in both sexes. With the description of this new species, the number of known species of the genus Euscorpiops from China is raised to 13 (five species found in Xizang, including the new species, and eight other species in Yunnan). A key to the species of the genus Euscorpiops from China is presented.


Introduction
The genus Euscorpiops has medium size scorpions in the family Scorpiopidae. Scorpions of this genus are distributed in South and Southeast Asia, including 27 species inhabiting the Oriental region from Pakistan to Vietnam (Kovařík et al. 2015;Ythier 2019). In China, the species of genus Euscorpiops were found in Xizang and Yunnan. Di et al. (2010) recorded ten species of Euscorpiops from China: E. asthenurus (Xizang), E. kamengensis (Xizang), E. karschi (Xizang), E. novaki (Xizang), E. puerensis (Yunnan), E. shidian (Yunnan), E. vachoni (Yunnan), E. validus (Yunnan), E. yangi (Yunnan), and E. xui (Yunnan). Di et al. (2011) added E. kubani to the fauna of Yunnan. Di et al. (2013Di et al. ( -2015 revised the fauna of the genus Euscorpiops in Xizang and provided the history of study of this genus, an updated checklist and the distribution and key of the order Scorpiones in China. Kovařík et al. (2015) revised the checklist and key of the genus Euscorpiops including eleven species distributing in China. Ythier (2019) described a new species E. zhangshuyuani found in Yunnan. Until now, 13 species of this genus are currently recognized as present in China (including the new species).

Materials and methods
Illustrations and measurements were produced using a Leica M205 stereomicroscope. Measurements followed Sissom (1990) and are given in mm. Trichobothrial notations followed Vachon (1974), and the morphological terminology mostly followed Hjelle (1990). The terminology of metasomal carination followed Vachon (1952), and the terminology of pedipalp chelal carinae followed Soleglad and Sissom (2001). Type series of the new species are deposited in the Museum of Hebei University, Baoding, China (MHBU).

Taxonomic treatment
Family Scorpiopidae Kraepelin, 1905Genus Euscorpiops Vachon, 1980  Diagnosis. Euscorpiops lii sp. nov. differs from all other species in the genus on the basis of the following combination of characters: yellow-brown colour, small size (length of adults less than 40.0 mm), 17 trichobothria on the external surface of pedipalp patella (5 eb, 2 esb, 2 em, 4 est, 4 et) and six or seven (usually six) trichobothria on the ventral surface of pedipalp patella, chela with an average length/width ratio of 3.7 in males (3.6-3.8, six adults) and 3.3 in females (3.2-3.4, six adults), pedipalp chela fingers on adult males and females scalloped, and pectinal teeth count 4-6 with five or six in males (usually six) and 4-6 (usually five) in females, pectinal fulcra present.  yellow-brown, while as metasoma with black-brown carinae; vesicle yellow, with a brown aculeus. Chelicerae yellow, with darker, yellow-brown fingers. Pedipalp yellowbrown, with black-brown carinae. Legs yellow. Sternum, yellow-brown. Genital operculum pectines, and sternites pale yellow.
Prosoma (Figs 5,7,8): Carapace with sparse, fine granules; lateral furrow, broad; anterior median furrow, broad and deep; posterior median furrow, deep; margin behind lateral eyes with granules, other margins smooth. Median eyes situated anteriorly compared to centre of carapace; three pairs of lateral ocelli with posterior-most one the smallest. Median ocular tubercle, coarse with granules and a median furrow. Lateral ocular tubercle with some granules around lateral eyes.
Mesosoma: Tergites densely covered with fine granules; tergite II to tergite VI with a median carina; tergite VII with two pairs of lateral carinae with big granules. Pectinal teeth count 6/6, fulcra small ( Fig. 9). Genital operculum subtriangular with genital papillae protruding (Fig. 9). Sternites smooth and shiny; segment VII with some big granules and four weak ventral carinae.
Legs: Trochanters with few setae. Femora dorsal surfaces with some small granules, externally with one granular carina, internally with two granular carinae. Patellae externally with one granular carina and internally with one dentate carina. Tibiae with few setae, without spurs. Basitarsi with few setae and some short spinules terminally and two lateral pedal spurs. Tarsi ventrally with a row of short and strong spinules. Tarsal ungues curved and hook-like.
The new species appears to be related to the other species of the genus Euscorpiops from Xizang: E. asthenurus and E. kamengensis. These are also the geographically closest species, but these species can be readily distinguished on the basis of the following combination of characters: (i) 17 trichobothria on the external surface of pedipalp patella (5 eb, 2 esb, 2 em, 4 est, 4 et) in E. lii sp. nov. (seven males  and 13 females), 18 (5/2/2/4/5) in E. asthenurus (two males and one female) and 19 (5/2/2/5/5) in E. kamengensis (two females); (ii) six or seven (usually six) trichobothria on the ventral surface of the pedipalp patella in E. lii sp. nov., while there are eight or nine in E. asthenurus, and seven in E. kamengensis.
The following main features can be used to distinguish E. lii sp. nov. from the other more geographically distant species of the genus Euscorpiops occurring in Xizang, E. karschi and E. novaki: (i) length of adults less than 40.0 mm in E. lii sp. nov. (seven males and 13 females) while the length of adults more than 45.0 mm in E. karschi (one male and one female) and E. novaki (one male); (ii) the pedipalp patella with 18 (5/2/2/4/5) external trichobothria in E. karschi (one male and one female) and 19 (5/2/2/5/5) in E. novaki (one male); (iii) the pedipalp patella with eight or nine ventral trichobothria in E. karschi (one male and one female) and nine in E. novaki (one male); (iv) the pectinal teeth count 4-6 with five, six (usually six) in males and 4-6 (usually five) in females in E. lii sp. nov., 7-9 in E. karschi (7-8 in three females, 8-9 in two males) and eight in E. novaki (one male).

Key to species of the genus Euscorpiops from China
(distribution map and feature datasets of species of Euscorpiops from China given in Fig. 31 and Table 2 Pedipalp chela fingers with non-scalloped (nearly straight) margins in male adults . "*" The colouration description did not seem to reflect much that of the photos of the specimens. "#" It maybe an immature. "?" There was no information or dubious description provided in papers. "$" It was recorded as 17 external trichobothria of pedipalp patella in the original description by Qi et al., (2005).