Liphistius linang, Peter J. Schwendinger, 2017

Peter J. Schwendinger, 2017, A revision of the trapdoor spider genus Liphistius (Mesothelae: Liphistiidae) in peninsular Malaysia; part 1, Revue suisse de Zoologie 124 (2), pp. 391-445 : 418-422

publication ID	https://doi.org/ 10.5281/zenodo.893555
DOI	https://doi.org/10.5281/zenodo.6042372
persistent identifier	https://treatment.plazi.org/id/4C30A452-FFFF-FFE8-BB55-F88939D7FBDE
treatment provided by	Plazi
scientific name	Liphistius linang
status	sp. nov.

Treatment

Liphistius linang View in CoL sp. nov.

Figs 15-16 View Fig. 15 View Fig. 16

Types: MHNG; male holotype (matured end XII.2001), 4 male paratypes (matured 14.IX., 1.X.1999, early XI.2000, end XII.2001) and 4 female paratypes (including allotype, moulted 12.II.2002); Malaysia, Kelantan, about 15 km E of Machang, Jeram Linang Waterfall , 5°44’34”N, 102°22’29”E, 50 m; 12.I.1999; leg. P.J. Schwendinger. GoogleMaps

Etymology: Name in apposition, taken from the Malay name of the type locality: jeram (= rapids), linang (tearful, weeping).

Diagnosis: Medium-sized, bicoloured species in both sexes. Similar to L. tioman , males distinguished by retroventral part of bipartite tibial apophysis carrying longer and bent megaspines; retrodorsal part of tibial apophysis developed as a small tubercle carrying a weaker megaspine ( Fig. 15A View Fig. 15 , G-I cf. Fig. 11A View Fig. 11 , G-I); tegulum with wide, distinctly dentate proximal edge ( Fig. 15D View Fig. 15 cf. Fig. 11B View Fig. 11 ); contrategulum without (or with very indistinct) ventral process, its distal edge finely dentate instead of ribbed, prodorsally with a wide gap before reaching hook-shaped dorsal apex ( Fig. 15B View Fig. 15 , E-F cf. Fig. 11C, F View Fig. 11 ); para-embolic plate large, distally wide, with coarsely dentate margins ( Fig. 15 View Fig. 15 A-F cf. Fig. 11 View Fig. 11 C- E); dorsal wall of sclerotised part of embolus proper not ending in protruding lobe, as wide as ventral wall ( Fig. 15B View Fig. 15 , E-F cf. Fig. 11 View Fig. 11 B-C, F); scopula on tarsi IV absent.

Description of male (holotype): Colour in alcohol (much darker in life): Carapace mostly light brown; pars cephalica brown except for indistinct grey-brown W-shaped pattern behind eye mound and light brown medial patch between eye mound and fovea; brown area on pars cephalica connected to brown flower-shaped area around fovea; long brown patches along lateral (wide) and posterior (very narrow) margins of pars thoracica and between coxal elevations. Chelicerae with proximal portion cream-coloured, distal portion dark brown. Palps in proximal half of femur and tibia and in distal half of patella light brown, mottled with dark spots, other parts dark brown; cymbium entirely very dark reddish brown. Legs mostly dark brown except for light brown distal half of all patellae and light brown proximal half of all femora (mottled with dark spots); leg tibiae (in contrast to those of palp) to tarsi entirely dark brown. Opisthosoma mostly light brown, mottled with dark spots laterally; tergites I-II almost entirely dark brown, tergite III light brown with extensive dark lateral and median patches, following tergites with distinct dark lateral spots and increasingly indistinct median spots, last two tergites tiny and entirely dark brown.

Bristles on carapace: Few short, weak bristles along all margins except posterior one, on coxal elevations, in front and behind fovea; longer, stronger bristles on, behind and in front of eye mound.

Cheliceral teeth: Ten small ones on promargin of cheliceral groove of each chelicera.

Scopula: Tarsi I-III with moderately dense scopula in distal two-thirds of ventral side, only distally divided by a short median stripe; tarsus IV entirely without scopula. Claws: Paired tarsal claws on anterior legs with 3-5 denticles, on posterior legs with 4-5 denticles; unpaired claws with one indistinct denticle or without.

Palp: Tibial apophysis situated distally, only slightly set back from anterior margin of palp ( Fig. 15A View Fig. 15 ), deeply divided: (a) retroventral part long and deep, pointing slightly away from axis of tibia, carrying three mediumsized, bent megaspines; (b) retrodorsal part much smaller and shorter, shaped like a low tubercle, carrying a single bent, relatively weak spine (i.e. a reduced megaspine); long bristle retroventrally below tibial apophysis weak ( Fig. 15A View Fig. 15 , G-H). Distal margin of cymbium with indistinct lobes ( Fig. 15B View Fig. 15 ). Paracymbium quite long and moderately deep, with an indistinct retrolateralproximal heel ( Fig. 15A, G View Fig. 15 ); cumulus indistinct, carrying a moderately compact group of long stiff bristles ( Fig. 15A, G View Fig. 15 ). Subtegulum without apophysis. Tegulum with wide, distinctly dentate proximal edge ( Fig. 15D View Fig. 15 ). Contrategulum without recognizable ventral process; prolateral surface with a few ribs, distal edge sharp in proventral part, finely dentate in prolateral part, with a deep gap in prodorsal part before reaching very narrow, slightly hook-shaped dorsal apex ( Fig. 15B, E View Fig. 15 ). Paraembolic plate large, its distal margin wide, strongly dentate and directed proventrad-distad ( Fig. 15 View Fig. 15 B-E); embolus proper relatively narrow, inclined prolaterad ( Fig. 15 View Fig. 15 A-D), dorsal and ventral walls of sclerotised part equally wide and lying close to each other, retrolateral wall enforced by five weak ridges ( Fig. 15E View Fig. 15 ); membranous part of embolus proper narrow, indistinct ( Fig. 15B View Fig. 15 ).

Measurements: Total length 14.22; carapace 5.83 long, 5.05 wide; opisthosoma 6.86 long, 4.31 wide; eye mound 0.91 long, 1.12 wide; palpal coxae 1.76 long, 1.23 wide; labium 0.49 long, 1.08 wide; sternum 2.55 long, 1.81 wide (1.03 on ventral surface); palp 9.66 long (2.55 + 1.91 + 3.53 + 1.67); leg I 17.64 long (4.80 + 2.30 + 3.82 + 4.61 + 2.11); leg II 18.67 long (4.80 + 2.30 + 4.02 + 5.20 + 2.35); leg III 20.48 long (4.95 + 2.35 + 4.26 + 6.27 + 2.65); leg IV 26.72 long (6.27 + 2.65 + 5.74 + 8.58 + 3.48).

Description of female (allotype): Colour in alcohol (much darker in life): As in male, except for carapace with more extensive dark areas, all of them interconnected; W-shaped pattern behind eye mound distinct; metatarsi of legs and palps mostly dark, with a small light zone at base; tibiae with dark proximal and subdistal annulations; light brown femora with indistinct (in comparison to tibiae) dark proximal and subdistal annulations; opisthosomal tergites III-VII with more extensive dark median patches; genital area darker than surrounding parts of genital sternite, with a white, bellshaped posterior zone ( Fig. 16F View Fig. 16 ).

Bristles on carapace: Stiff bristles as in male, plus an additional pair just anterior to fovea.

Cheliceral teeth: Nine strong teeth on promargin of left cheliceral groove, ten on right side.

Claws: Palpal claw with three denticles on right side, none on left side. Paired claws with two denticles on anterior legs, 2-3 denticles on posterior legs; unpaired claws with 1-2 denticles on legs I-III, none on leg IV. All tarsi without scopula.

Vulva: Posterior margin of genital sterite invaginated ( Fig. 16F View Fig. 16 ). Vulval plate ( Fig. 16 View Fig. 16 A-E, illustrations of paratypes) with pigmentation and sclerotisation completely lost in median zone. Posterior stalk reduced to a small isolated, ventrad-bent posterior sclerite at some distance from or on posterior margin of genital sternite; posterior stalk and poreplate widely separated from each other. Genital atrium slightly sunken below level of poreplate, carrying numerous hairs on both sides of remnant of posterior stalk. Poreplate with indistinctly outlined lateral and posterior margins, these not bulging from ventral side of plate; anterior margin distinctly and widely invaginated, forming two more or less pronounced anterolateral lobes. CDO relatively small, wider than long, transversally slit-like or triangular, situated in unpigmented or weakly pigmented area of poreplate ( Fig. 16A View Fig. 16 , C-D, paratypes). Ventral receptacular cluster quite large and racemose, longitudinally divided into two lateral subclusters, its individual vesicles globular, about as long as wide ( Fig. 16B, E View Fig. 16 , paratypes).

Measurements: Total length 17.25; carapace 5.93 long, 5.00 wide; opisthosoma 7.89 long, 6.13 wide; eye mound 0.82 long, 1.04 wide; palpal coxae 1.91 long, 1.37 wide; labium 0.64 long, 1.37 wide; sternum 2.65 long, 2.11 wide (1.27 on ventral surface); palp 10.00 long (3.24 + 1.86 + 2.30 + 2.60); leg I 12.40 long (3.77 + 2.16 + 2.50 + 2.50 + 1.47); leg II 12.90 long (3.82 + 2.21 + 2.55 + 2.75 + 1.57); leg III 13.73 long (3.92 + 2.25 + 2.60 + 3.24 + 1.72); leg IV 19.71 long (5.10 + 2.55 + 4.07 + 5.54 + 2.45).

Remark: In the female allotype the long spinnerets (anterior and posterior laterals) are bent anteriad, which is an artefact resulting from having been pressed against the wall of the vial in that position for some time.

Variation: Carapace lengths in males (n=5) 4.91- 6.15, carapace widths 4.19-5.09; in females with welldeveloped vulval plates (n=4) 5.53-5.90 and 4.29-5.03, respectively. All males lack a scopula on tarsus IV. Variation in the shape of the retrolateral tibial apophysis of the male palp is shown in Fig. 15 View Fig. 15 G-I; variation in the shape of the prolateral-distal edge of the contrategulum in Fig. 15 View Fig. 15 E-F; variation in the shape of the vulval plate in Fig. 16 View Fig. 16 A-E.

Distribution: Known only from the type locality ( Fig. 1 View Fig. 1 , locality 13) in the northeastern corner of peninsular Malaysia. At the same locality, only metres away from burrows of L. linang sp. nov., a single female of another, much larger, dark-coloured Liphistius species was found. This female (mentioned under Liphistius sp. at the end of the presentation of the malayanus -group) appears to be more closely related to L. endau than to the geographically closer L. negara sp. nov.

Biology: Spiders of this species were quite abundant in a lush rain forest along the stream above the Jeram Linang Waterfall. The burrows had a single trapdoor and mostly nine signal lines (up to 4 cm long) spread over soil surface. Trapdoors of penultimate males (n=5) were 1.2-2.0 cm long and 1.8-2.3 cm wide, those of reproductive females (with egg case; n=5) 1.2-1.7 cm and 1.8-2.3 cm, respectively.

Two males matured in mid-September and at the beginning of October of the year when they were collected. The three other males were raised from eggs (hatched in late May); one of them matured in November of the following year, the other two one year later in December. Less than one and a half years from hatching to maturation is exceptionally short for a Liphistius male, and this may be due to conditions in captivity in Geneva. Three females built egg cases in captivity between early February and early March, two of them were 1.7-1.9 in diameter, 1.25-1.3 cm high, and contained 40 and 84 light beige-yellow eggs suspended on a thin mesh of fine silk threads. The first generation females in captivity moulted in April, July and September.