﻿Four new species of the spider genus Liphistius (Araneae, Mesothelae, Liphistiidae, Liphistiinae) from Myanmar

﻿Abstract Four new species of Liphistius belonging to the birmanicus species group are described from Myanmar based on both sexes: L.kalaw Zhan & Xu, sp. nov. (♂♀), L.kanpetlet Zhan & Xu, sp. nov. (♂♀), L.nawngau Zhan & Xu, sp. nov. (♂♀) and L.rostratus Zhan & Xu, sp. nov. (♂♀). Currently, Myanmar stands as the westernmost country where Liphistius is distributed, with the new species L.kanpetletsp. nov. being found in the westernmost region of Myanmar.

Following an examination of specimens collected from Myanmar, we identify and describe four new Liphistius species, each restricted to a limited range, all belong to the birmanicus-group.

Material and methods
All specimens were collected alive in Myanmar (Figs 1, 2) and transported the subadult individuals to the laboratory, where they were reared until reaching maturity.Right legs were removed from adults, preserved in absolute ethanol, and stored at −80 °C for genome DNA extraction.The remaining parts of each specimen were preserved in 80% ethanol as vouchers for morphological examination.These vouchers are currently deposited at the School of Life Sciences, Hubei University, Wuhan, Hubei Province, China (HUBU).In the future, the specimens will be deposited at two locations: School of Life Sciences, Hubei University, Wuhan, Hubei Province, China, and the Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, Nay Pyi Taw, Myanmar (CAS-SEABRI).For morphological examination, we used an Olympus SZ51 stereomicroscope to dissect the specimens.Soft tissues of vulvae were removed using 10 mg/ml pancreatin, allowing for a minimum 3-hour digestion period at room temperature.Male palps and female genitalia were photographed using an Olympus BX53 compound microscope equipped with a digital camera CCD.Compound-focused images were generated using Helicon Focus v. 6.7.1.Specimen coloration was described in alcohol.All measurements were carried out under a Leica M205C stereomicroscope using Leica Application Suite v. 4 software and are given in millimeters.Measurements of legs and palp are presented in the following order: leg total length (femur, patella, tibia, metatarsus [absent on palp], tarsus).
Comments on Liphistius in Myanmar.Eleven named Liphistius species in Myanmar were grouped into three species-groups: the birmanicus-group, comprising nine valid species; the bristowei-group, consisting of one known species; and the trang-group, also containing one known species (Schwendinger 1990;Schwendinger et al. 2022;Sivayyapram et al. 2024).All named Liphistius species of the birmanicus-group were described based on both sexes, except for L. hpruso Aung, Xu, Lwin, Sang, Yu, Liu, Liu & Li, 2019, which is only known from females.In this study, four new Liphistius species belonging to the birmanicus-group are described, identified according to the morphology of their copulatory organs in both sexes.
Variation.Females vary in body size.The range measurements of females (N = 8): BL 8. .The number of denticles on the promargin of cheliceral groove varies from 11 to 14 (N = 8).
Etymology.The species epithet "kalaw" refers to the type locality, Kalaw Township; it is treated as a noun in apposition.
Vulva: approximately rectangular poreplate (PPl) wider than long with smoothly curved posterior margin; with pair of large anterior lobes and pair of small anterolateral lobes, 2 anterior lobes separated from each other, but close to anterolateral lobes; central dorsal opening (CDO) small, situated in center of poreplate (PPl); racemose receptacular cluster (RC) long and narrow; posterior stalk (PS) axe-shaped; genital atrium (GA) with slightly sclerotized lateral margins (Fig. 6).
Variation.Females vary in body size.The range of measurements of females (N = 5): BL 9. .The number of denticles on the promargin of cheliceral groove varies from 10-13 (N = 5).
Etymology.The species epithet "kanpetlet" refers to the type locality, Kanpetlet Township; it is treated as a noun in apposition.
Etymology.The species epithet "nawngau" refers to the type locality, Nawng Au Village; it is treated as a noun in apposition.

Figure 1 .
Figure 1.Map showing the collecting localities of the Liphistius species in Myanmar, China (L.nabang), and Thailand (L.lahu, L. metopiae).Blue circles refer to four new species described in this study, black circles indicate known and one putative species.

Figure 2 .
Figure 2. Microhabitat and general somatic morphology of four new Liphistius species.A microhabitat B burrow with trapdoor open C, E-G male dorsal view C L. kanpetlet sp.nov.D, E L. rostratus sp.nov.F L. kalaw sp.nov.G L. nawngau sp.nov.Scale bars: 0.5 mm (D); 5 mm (C, E-G).
vs fig.13E in Schwendinger et al. 2022), and from L. pinlaung by the cumulus (Cu) which has shorter spines (Fig. 3A-C vs fig.4C in Aung et al. 2019).The female of L. kalaw sp.nov.can be distinguished from that of L. hpruso by the relatively wider posterior stalk (PS) (Fig. 4C vs fig.3B-E in Aung et al. 2019).