Liphistius lahu Schwendinger, 1998 Figs 1, 4-5 Liphistius lahu Schwendinger, 1998: 17-19, fig. 1A-H (description of males and females). – Schwendinger, 1999: fig. 1A-H (reprint of illustrations in Schwendinger, 1998). Holotype: MHNG-ARTO-0024737; male; Thailand, Chiang Mai Province, Fang District, Doi Angkhang, 1540 m, 19°55’10”N, 99°02’55”E; 27.VIII.1990; leg. P.J. Schwendinger. Paratypes: MHNG-ARTO-0024739; 1 male; collected together with the holotype. – MHNG-ARTO-0024740 to 24745; 6 female paratypes; collected at the type locality; 27.VIII.1990 and 25.IX.1986; leg. P.J. Schwendinger. Other material: MHNG; 1 female; Thailand, Chiang Mai Province, Fang District, Doi Pha Luang, 1600 m, 20°02’37”N, 99°06’14”E; 3.XI.1990; leg. P.J. Schwendinger. No new material available. Diagnosis: Males distinguished by a moderately deep tibial apophysis (depth/length ratio ~ 1.4, Fig. 4F), by a widely rounded retrolateral-proximal heel on paracymbium (Fig. 4 H-J), by an indistinctly elevated prolateral part of the distal contrategular edge (Fig. 4E, G), and by short para-embolic plate not separated by an invagination from retroventral edge of embolus complex (Fig. 4 C-E). Females distinguished by ventral side of poreplate without anterolateral processes and by an indistinct step between anterior lobes and lateral poreplate margins; posterior stalk axe-blade-shaped, about half as long as poreplate (Fig. 5). Additions to description: Medium-sized spiders with brown colouration in both sexes and annulated legs and palps in females and juveniles (in large spiders less distinct than in small ones, annulations thus fading as females become older and larger). Males with scopula weak on tarsi I-II, slightly denser on tarsi III-IV, covering distal 4/5 of tarsus I and distal 5/6 of tarsi II-IV. Male palps with moderately deep tibial apophysis (depth/length ratio ~ 1.4), not set back from distal margin of tibia, carrying four long, pointed apical megaspines (Fig. 4F; Schwendinger, 1998: fig. 1A-C; Schwendinger, 1999: fig. 1A-C); paracymbium short, with an almost flat distal surface and with a widely arched retrolateral-proximal heel (Fig. 4 H-J); cumulus indistinct, carrying a group of 5-6 long, strong bristles (Fig. 4 H-J; Schwendinger, 1998: fig. 1B-C; Schwendinger, 1999: fig. 1B-C); subtegulum without apophysis (Fig. 4E); proventral process of contrategulum conical, with narrowly rounded apex in dorsal view (Fig. 4 A-C); prolateral part of distal edge of contrategulum developed as a low (not elevated as in L. metopiae sp. nov.) keel (Fig. 4E, G); no wrinkles on dorsal side of contrategulum, a pronounced proximal ledge on its retrodorsal side (Fig. 4 A-C); distal edge of contrategulum very wide, with narrowly rounded dorsal apex (Fig. 4 A-C; Schwendinger, 1998: fig. 1D-E; Schwendinger, 1999: fig. 1D-E); tegulum large, its distal margin not elevated, its proximal edge widely arched, coarsely serrate, bent and distinctly overhanging membranous area of contrategulum below it (Fig. 4 C-D; Schwendinger, 1998: fig. 1A-B; Schwendinger, 1999: fig. 1A-B); para-embolic plate very short, not separated from retroventral edge of embolus complex by an invagination (Fig. 4 C-E); sclerotised part of embolus proper strengthened by 3-4 distally dentate longitudinal ribs reaching apex, narrowly divided from distinctly shorter membranous embolus part; at base of membranous embolus part a weakly pigmented area with only 3-4 longitudinal wrinkles and with a wide and asymmetrical distal margin (Fig. 4 C-D, G). Females with more or less distinctly annulated legs and palps; uterus externus with a small pair of lateral pockets (as illustrated for L. ferox sp. nov., Fig. 11 I-J, N, P and Fig 12D, F); vulval plate with several hairs on lateral folds; poreplate wider than long, with a pair of pronounced, rounded lobes on anterior margin, without anterolateral processes; an indistinct step between anterior lobes and lateral poreplate margins (Fig. 5 E-F, H); receptacular cluster racemose, quite long, almost reaching or slightly surpassing anterior margin of poreplate (Fig. 5; Schwendinger, 1998: fig. 1F-H; Schwendinger, 1999: fig. 1F-H); posterior stalk axe-blade-shaped, its anterior portion narrow, its posterior margin wide and arched, narrower than poreplate. Variation: For carapace measurements and prefoveal setae counts see Table 1. All specimens examined have well-developed AME. Variation in the shape of the paracymbium and of the distal edge plus the proventral process of the contrategulum of males is shown in Fig. 4 H-J and Fig. 4 A-C, respectively. Variation in the shape of the vulval plates of five females is shown in Fig. 5. Relationships: Palp morphology of males is very similar in L. lahu and L. metopiae sp. nov., indicating that these two species are not only geographically but also phylogenetically close to each other. Distribution: Liphistius lahu is known from two localities in the mountains of the northern Thai province of Chiang Mai, at and close to the border with the Shan State of Myanmar (Fig. 1). This species can probably be found on both sides of that border. Biology: Information is given in the original description (Schwendinger, 1998: 19). No new specimens or new biological information are available.

Published as part of Schwendinger, Peter J., Huber, Siegfried, Lehmann-Graber, Christina, Ono, Hirotsugu, Aung, Mu Mu & Hongpadharakiree, Komsan, 2022, A taxonomic revision of the Liphistius birmanicus-group (Araneae: Liphistiidae) with the description of five new species, pp. 375-424 in Revue suisse de Zoologie 129 (2) on pages 380-382, DOI: 10.35929/RSZ.0083, http://zenodo.org/record/7761487