Lamania bokor, Peter J. Schwendinger & Ondřej Košulič, 2015

Peter J. Schwendinger & Ondřej Košulič, 2015, Two new species of armoured spiders from Vietnam and Cambodia (Araneae: Tetrablemmidae: Pacullinae), Revue suisse de Zoologie 122 (2), pp. 423-436 : 428-430

Lamania bokor sp. nov.

Figs 4-5

Holotype: MHNG (sample THKH- 13 /06 ); male; Cambodia, Kampot Province, Phnom (= Mount) Bokor , Popokvil Waterfall (10 ° 39 ’ 34 ”N, 104 °03’05”E), 910 m; 24.XII. 2013; leg. P. Schwendinger .

Paratypes: 1 male, 6 females ( MHNG) collected together with the holotype. – 1 female ( NMP), Phnom Bokor (10 ° 37 ’ 42 ” N, 104 °05’ 36 ” E), 700 m; 14.XI. 2012; leg. O. Košulič .

Etymology: Named after the mountain on which the types were found. Noun in apposition.

Diagnosis: The new species differs from L. kraui Shear, 1978 by larger size [carapace length and width in L. bokor sp. nov. 1.95-2.09 and 1.54-1.67 (n= 9), in L. kraui 1.37-1.61 and 1.09-1.28 (n= 22)] and by the cephalic part of the carapace being posteriorly more strongly elevated in both sexes ( Fig. 4 B cf. Fig. 6 A). Embolus of palpal organ with quadrangular (instead of triangular) subterminal lamella and with narrower, scale-like (instead of wide and truncate) embolic part ( Fig. 4 D-H cf. Fig. 6 E-H). Vulva not clearly distinguishable from that of L. kraui ( Fig. 5 cf. Fig. 7; see also “Taxonomic remarks”).

Description of male (holotype): Colour (in alcohol) of sclerotised parts mostly dark brown, except for slightly lighter leg patellae and apical portions of leg femora and tibiae, and distinctly lighter basal (bulbous) part of palpal organ; membranous parts of opisthosoma light brown. Clypeus and thoracic part of carapace without modifications, cephalic part of carapace clearly highest in its posterior portion ( Fig. 4 B). Carapace with numerous elevated setal bases; fovea not discernible ( Fig. 4 A). Total length 4.46. Carapace 1.98 long, 1.58 wide. Eye sizes and interdistances: PME 0.15 long, separated by 0.08; ALE 0.15 long; ALE-PLE 0.03; PLE 0.13 long, separated by 0.76. Labium 0.47 long, 0.65 wide. Sternum 1.13 long, 1.10 wide; sternal apophysis a small rounded knob carrying strongly conical setal bases. Chelicerae without modifications; two indistinct teeth distal to median lamina.

Palp 1.96 long (0.66 + 0.35 + 0.57 + 0.38). Cymbium ( Fig. 4 D) short, its apex with two distinct lobes of similar size. Tibia with low, wide proventral process ( Fig. 4 D); its ventral side with smooth and plane surface (zone of contact with palpal organ, Fig. 4 E-F). Palpal organ with large, globular base; embolus short and bifid, its proximal portion with a low boss on anterior side ( Fig. 4 F, H), its apical portion divided into a quadrangular subterminal lamella with pointed, slightly outward-bent dorsodistal corner, and into a relatively narrow (about as wide as subterminal lamella at base) scale-like embolic part ( Fig. 4 D-H).

Legs 3241. No conical setal bases present on tibiae and metatarsi of anterior legs; all articles of legs and palps with essentially smooth surface (apart from pitlike setal bases). Leg I with thin but distinct ventral scopula of short, sigmoid serrate setae spread over almost entire length of tarsus and over distal twothirds of metatarsus (see paragraph “Scopulae in Tetrablemmidae ”); other legs without scopula. Paired leg claws with a row of 11-12 teeth on anterior legs, 8-9 on posteriors; unpaired leg claws with one denticle. Leg I 7.37 long (2.27 + 0.66 + 2.08 + 1.51 + 0.85), leg II 6.29 long (1.92 + 0.63 + 1.64 + 1.34 + 0.76), leg III 5.41 long (1.61 + 0.60 + 1.31 + 1.23 + 0.66), leg IV 7.14 long (2.17 + 0.63 + 1.92 + 1.73 + 0.69).

Opisthosoma 3.02 long, 2.17 wide. Dorsal scutum large, 2.90 long, 2.17 wide, mostly smooth except for numerous pit-like setal bases and several indistinctly raised mounds (pair near posterior margin being largest). Microplates on anterior side strongly conical, all others flat ( Fig. 4 B). Three strap-like lateral plates (lower one longest, median one shortest) and three strap-like posterior plates (upper one longest, lower one shortest). Pulmonary plate 2.14 long, 1.58 wide, completely fused with stigmal plates, with anterior pair of ventrolateral plates and with postgenital plate (linked by a sclerotised suture); posterior part evenly covered with wart-like setal bases, booklung covers smooth, anterior part carrying several distinct conical setal bases, including three (on right side) and four (on left side) large ones [corresponding to “large, black, seta-bearing teeth” in L. kraui (see Shear, 1978: 43, fig. 116 and Fig. 6 B)] above booklung covers ( Fig. 4 C, minor conical setal bases omitted); genital region elevated to a low volcano-shaped mound with the genital orifice in its centre. Median ventrolateral plates separated, with a single very short but wide bridge fragment between them (see Schwendinger, 2013: 657, 659, fig. 36 A-D for explanation). Preanal plate 0.30 long, 0.76 wide, fused with posterior ventrolateral plates (discernible by darker colour and different surface texture). Anal plate 0.28 long, 0.74 wide.

Description of female (allotype): As in male, except for the following. Colour (in alcohol) slightly darker than in male holotype, membranous parts of opisthosoma yellowish brown. Total length 4.55. Carapace 1.94 long, 1.59 wide. Eye sizes and interdistances: PME 0.14 long, separated by 0.10; ALE 0.15 long; ALE-PLE 0.03; PLE 0.14 long, separated by 0.80. Labium 0.44 long, 0.66 wide. Sternum 1.20 long, 1.10 wide.

Palp 1.83 long (0.52 + 0.25 + 0.38 + 0.68), without claw. Legs 3214. Leg I without scopula. Paired leg claws with a row of 13-14 teeth on anterior legs, eight on posteriors. Leg I 7.08 long (2.17 + 0.63 + 1.95 + 1.48 + 0.85), leg II 6.12 long (1.86 + 0.60 + 1.58 + 1.32 + 0.76), leg III 5.22 long (1.58 + 0.57 + 1.23 + 1.18 + 0.66), leg IV 7.11 long (2.16 + 0.63 + 1.89 + 1.72 + 0.71).

Opisthosoma 3.12 long, 2.17 wide. Dorsal scutum 2.77 long, 1.73 wide, distinctly more rugous than in males, pits and elevations more pronounced. Microplates on anterior side smaller and less strongly elevated than in males. Four strap-like lateral plates (uppermost and lowermost longest, second from below shortest) and three strap-like posterior plates. Pulmonary plate 1.89 long, 1.48 wide, not fused with postgenital plate; genital region essentially flat, posterior edge elevated above postgenital plate. Postgenital plate 0.19 long, 0.71 wide. Two bridge fragments lying between pair of median ventrolateral plates. Preanal plate 0.36 long, 0.71 wide. Anal plate 0.28 long, 0.66 wide.

Vulva ( Fig. 5 showing five paratypes) with short, wide genital atrium with relatively large porepatches on lateral sides and with a largely transparent (except for base and lateral margins), flattened anterior collar.

Taxonomic remarks: The vulva of L. bokor sp. nov. is very similar to that of L. kraui , and at present a clear distinction cannot be made. Nevertheless two differences were observed which may or may not be consistent and of diagnostic value: 1. The cuticular bases of the gland ducts that stick out of the pores of the porepatches are evenly tapering in L. bokor sp. nov., whereas in L. kraui they are shaped like papillae, basally wide and abruptly tapering to a tiny pointed tip. 2. In the L. bokor sp. nov. vulvae examined the anteromedian wall (roof) of the genital atrium (between the spermathecae and below the anterior collar) in dorsal view is more distinctly arched anteriad than in L. kraui .

Variation: Carapace length in two males (seven females) ranges 1.95-1.98 (1.94-2.09), carapace width 1.54-1.58 (1.56-1.67). Both males and one female have only one bridge fragment between both median ventrolateral plates, five females have two, in the remaining female this is not visible due to a shrunken opisthosoma. The number of enlarged conical setal bases above the booklung covers ranges 3-5. Variation in the shape of the vulva of five females is shown in Fig. 5 A-E.

Relationships: The new species is most similar (with respect to shape of carapace and of palpal organ) and probably most closely related to an undescribed species from southern Thailand (Phang Nga Province), which is also geographically the closest congeneric species to L. bokor sp. nov. available at present. The localities of both species are separated by about 1200 km on the land route and by over 600 km in a direct line across the Gulf of Thailand. The latter route may have been open to spiders in periods of lowered sea levels during the Cenozoic, but it is quite unlikely that the habitats there were suitable for colonization by Lamania . Extant Lamania spp. have only been found on the floor of humid evergreen broadleaf forests. Despite intensive sifting of leaf litter in evergreen forests of other parts of Thailand, no Lamania (or Paculla ) have been found there.

Distribution and habitat: This species is only known from two localities (separated by about 7 km) on Mount Bokor , at the southern end of the Elephant Mountains, near the coast of Cambodia ( Fig. 1, triangle). The specimens examined were sifted from leaf litter and collected from inside pieces of decaying wood on the floor of evergreen forests between about 700 m and 900 m.