Liphistius laoticus, Schwendinger, Peter J., 2013

Schwendinger, Peter J., 2013, On two Liphistius species (Araneae: Liphistiidae) from Laos, Zootaxa 3702 (1), pp. 51-60 : 56-59

Liphistius laoticus sp. n.

Figures 2 C–D, 4A–J, N–Q

Material. LAOS: Champasak Province, Bolaven Plateau, SW of Pakxong, near Tad Fane (= Fane Waterfall) (15°10’54”N, 106°07’38”E), 930 m; male holotype (matured 31.VII.1997), 5 male paratypes (matured 30.VII., 7.VIII., 8.VIII., 9.VIII, 27.VIII.1997) and 3 female paratypes (one of them the “allotype”, moulted 4.I.1997); 26.XII.1996. Same locality, 900 m; 1 female paratype; 2.X.2010 (sample LT-10/27). NW of Pakxong, Tham Champee (= Champee Cave) (15°12’04”N, 106°08’07”E), 980 m; 1 male paratype and 3 female paratypes; 2.X.2010 (sample LT-10/26). All specimens collected by P.J. Schwendinger. One male and one female paratype deposited in SMF, all other specimens in MHNG.

Etymology. The species epithet, a latinized adjective, refers to the country in which this species occurs.

Diagnosis. Males of the new species are similar to those of L. thoranie Schwendinger, 1996 , differing in a relatively wider ventral sternal surface with a heart-shaped posterior part ( Fig. 2 D, cf. Fig. 2 E), by palp (in ventral view) with a basally wider retrolateral tibial apophysis ( Fig. 4 A, cf. Schwendinger 1996: fig. 48) carrying in its ventral part two long and one shorter apical spines that are continuously tapering towards the tip, and in its dorsal part a very short apical spine that is thick at base and abruptly tapering to a narrow apex in its distal third ( Fig. 4 I) (in L. thoranie all apical spines are abruptly tapering; two of them are broken off in the illustration by Schwendinger 1996: figs 46–48); the cumulus is slightly more elevated, its thick bristles in a less compact group; the retrolateral heel of the paracymbium is less pronounced ( Fig. 4 J, cf. Fig. 4 K); the paraembolic plate is narrower ( Fig. 4 D, cf. Fig. 4 M). Females of the new species are very similar to those of L. ochraceus Ono & Schwendinger, 1990 , differing in a poreplate with a slightly longer and posteriorly wider posterior stalk ( Fig. 4 N–Q, cf. Schwendinger 1996: figs 80–82).

Description. MALE (holotype). Colour in alcohol: Most of body light brown (dark brown when alive). Carapace with light longitudinal area behind eye tubercle and indistinct light patches in posterior part of pars thoracica. Chelicerae light grey-brown distally, cream-coloured proximally. Femora and patellae of legs and palps speckled with grey-brown (speckles confluent on dorsal side of palpal femora); no dark annulations on tibiae to tarsi. Cymbium mostly reddish brown except for a light distal zone. Two anteriormost opisthosomal tergites uniformly medium brown; tergites III–VI with increasingly larger, light brown, longitudinal areas separating three medium brown areas; on tergites VII–X medium brown areas becoming more extensive again.

Total length 14.1. Carapace 6.0 long, 5.2 wide, set with quite few short, blunt-tipped hairs scattered in peripheral areas (not in central area). Ocular tubercle 0.91 long, 0.99 wide. Eye sizes and interdistances: AME 0.04, ALE 0.61, PME 0.33, PLE 0.50; AME–AME 0.13, AME–ALE 0.12, PME–PME 0.06, PME–PLE 0.05, ALE–PLE 0.03. MOQ 0.38 long, front width 0.21, back width 0.58. Labium 0.7 long, 1.1 wide. Sternum 2.5 long, 2.0 wide (1.1 on ventral surface); posterior part of ventral surface heart-shaped, clearly delimited and set with longer and stronger setae than indistinctly delimited anterior part; a light central spot present between both parts ( Fig. 2 D). Border between labium and sternum indistinct (without a distinct suture as in females). Maxillae 2.0 long, 1.3 wide. Promargin of cheliceral groove with 10 small teeth on left side and 11 on right side. Paired tarsal claws of first leg with four teeth, those of other legs with 4–5 teeth; unpaired claw with two tiny denticles on legs II and IV, three on legs I and III. Lengths of limbs: palp 9.8 (2.9 + 1.8 + 3.4 + 1.7); leg I 16.9 (4.7 + 2.3 + 3.5 + 4.3 + 2.1); leg II 18.2 (4.9 + 2.4 + 3.7 + 4.8 + 2.4); leg III 20.3 (5.0 + 2.4 + 4.1 + 6.0 + 2.8); leg IV 26.1 (6.1 + 2.6 + 5.4 + 8.1 + 3.9). Opisthosoma 5.7 long, 3.6 wide.

Pedipalps ( Fig. 4 A–E, I–J) with retrolateral tibial apophysis carrying four strong apical spines, the ventral two of them long and continuously tapering to tip, the third one shorter and also continuously tapering, the dorsal one very short and abruptly tapering ( Fig. 4 I); other spines on tibial apophysis subapical and distinctly weaker. Paracymbium medium-sized, with a distinctly projecting retrolateral-proximal heel ( Fig. 4 A, J); cumulus slightly elevated, carrying a relatively dispersed group of long thick bristles. Subtegulum without apophysis. Contrategulum with sharp dorsodistal edge rising to rounded angle; dorsal surface of contrategulum without proximal ledge; ventral contrategular process relatively large, with narrowly rounded apex ( Fig. 4 E). Tegulum relatively large, its proximal edge coarsely dentate and widely arched, its distal edge distinct, narrow, somewhat truncate, on its retrolateral side separated by a narrow unpigmented zone from contrategulum ( Fig. 4 B–C). Paraembolic plate relatively narrow, with a narrowly rounded apex ( Fig. 4 D); divided embolus fairly short, only little surpassing paraembolic plate and dorsodistal edge of contrategulum ( Fig. 4 A–D).

FEMALE (“allotype”). Colour as in male, but with more extensive light patches on carapace almost completely encircling a darker (as the periphery), indistinctly flower-shaped central area around fovea. Light brown areas on all opisthosomal tergites, these everywhere more extensive than in male. Indistinct, medium brown, proximal and subdistal annulations on leg tibiae and tarsi and on palpal tibiae, subproximal annulations on metatarsi of legs and palps; palpal tarsi uniformly medium brown. Coxae of legs I–II and of palps, and ventral side of chelicerae light reddish brown (darker than in male).

Total length 17.0 mm. Carapace 6.6 long, 5.4 wide. Ocular tubercle 0.91 long, 0.99 wide. Eye sizes and interdistances: AME 0.04, ALE 0.60, PME 0.30, PLE 0.44; AME–AME 0.13, AME–ALE 0.11, PME–PME 0.08, PME–PLE 0.08, ALE–PLE 0.10. MOQ 0.46 long, front width 0.24, back width 0.56. Labium 0.9 long, 2.3 wide. Sternum 4.1 long, 2.8 wide (2.0 on ventral surface), not divided into two unequal parts as in male. Border between labium and sternum clearly marked by deep suture ( Fig. 2 C). Maxillae 2.3 long, 1.5 wide. Promargin of cheliceral groove with 10 teeth on left side, 11 on right side. Paired tarsal claws of legs with 3–4 teeth; unpaired claw with four denticles on legs I–II, three/five denticles on leg III, and four/six denticles on leg IV; pedipalpal claws with three tiny denticles. Hairs spread over leg coxae and labium, and hairs in distal part of maxillae and sternum being distinctly longer and stronger than those in male. Lengths of limbs: palp 10.7 (3.4 + 2.0 + 2.6 + 2.7); leg I 13.1 (4.0 + 2.2 + 2.7 + 2.7 + 1.5); leg II 14.5 (4.3 + 2.4 + 2.9 + 3.1 + 1.8); leg III 15.6 (4.5 + 2.4 + 3.0 + 3.7 + 2.0); leg IV 21.6 (5.7 + 2.8 + 4.4 + 5.9 + 2.8). Opisthosoma 7.6 long, 5.4 wide.

Vulva ( Fig. 4 N). Poreplate simple, widely quadrangular, with moderately thick anterior and lateral rims without protuberances; a characteristic unpigmented area between each short posterior margin (without thickened rim) of poreplate and base of posterior stalk; receptacular cluster relatively simple, almost digitiform; posterior stalk medium-long, posteriorly wider than anteriorly, with widely rounded posterior margin. Genital atrium without lateral hairs.

Variation. One male paratype from the type locality lacks its right AME. The characteristic light spot in the centre of the sternum is difficult to see in the male most strongly bleached by alcohol preservation. One female lacks its right anterior median spinneret, having only a pigmented spot with bristles where the base of the spinneret should be. Variation in the shape of the contrategular processes of four males is shown in Fig. 4 E–H, variation in the shape of the poreplates of four females in Fig. 4 N–Q. The “allotype” has no hairs in its genital atrium ( Fig. 4 N), one female paratype has two hairs on one side only ( Fig. 4 Q), the two others have up to seven hairs on both sides ( Fig. 4 O –P).

Measurements of males (n = 7) range: body length 11.5–14.0, carapace length 4.8–5.9, carapace width 4.1–5.2. The corresponding maximal measurements in females (n = 7) are: 18.0, 6.5, 5.5.

Relationships. Liphistius laoticus sp. n. is a member of the trang -species group, as are all Liphistius species in nearby northeastern Thailand. Medium size, quite uniformly brown body colouration, and similarities in male and female copulatory organs (e.g. long and thick bristles on slightly or moderately elevated cumulus; distinct contrategular process; simple, more or less digitiform receptacular cluster) identify the new species as belonging to species complex B (Schwendinger 1996), later inappropriately called superspecies B (Schwendinger 1998), a subgroup which includes also L. erawan Schwendinger, L. tham Sedgwick & Schwendinger, L. thoranie , L. pusohm Schwendinger, L. onoi Schwendinger and L. ochraceus . Liphistius ochraceus (especially females which also have modifications at the posterior margins of the poreplate, Schwendinger 1996: figs 80–82 cf. Fig. 4 N–Q; males are without a retrolateral-proximal heel on the paracymbium, Fig. 4 L) and L. thoranie (especially males which also have a distinct retrolateral-proximal heel on their paracymbium, Fig. 4 K cf. Fig. 4 A, J) are morphologically most similar to the new species. Liphistius thoranie is geographically closer and thus regarded as the closest know relative of L. laoticus sp. n.

Distribution and habitat. The types of the new species were collected from two localities on the Bolaven Plateau of southern Laos. Siegfried Huber (pers. comm.) has recently found Liphistius (probably conspecific) also at the nearby Tad Itou. All spiders were found on earthbanks near waterfalls ( Tham Champee is actually a waterfall and not a cave as the Laotian name indicates). These localities probably receive considerably more humidity during the dry season than other areas on the plateau, most of which is under some kind of cultivation (predominantly coffee).

Biology. The six males from the type locality became mature between the end of July and the end of August (30.VII., 31.VII., 7.VIII., 8.VIII., 9.VIII., 27.VIII.1997), after 7–8 months in captivity; the male from Tham Champee matured in early October (9.X.2010), only a week after being captured. Females with egg cases moulted between late December and early January, one of them again in May and August. Three egg cases were found in the field in late December; two others were constructed in captivity in late November. These were 1.7–2.4 cm wide and 1.3–1.7 cm high, and contained 45–88 cream-coloured or light yellow eggs wrapped in a thin membrane and suspended above the bottom of the egg case with very fine threads.

Burrows of three juvenile males were T-shaped (with two trapdoors), all other burrows were unbranched and closed by a single trapdoor with its hinge on the upper side or slightly laterally. In penultimate males the doors were 1.6–2.1 cm wide and 1.0– 1.6 cm long; in females up to 2.7 cm wide and up to 2.1 cm long. Six to eight signal lines, up to 6.5 cm long, were spread over the soil surface or (rarely) stones. The largest burrow was 16 cm long.

One female (from Tham Champee; with egg case) and one male (from Tad Fane; matured 7.VIII.1997) were carrying ectoparasitic mites of the laelapid genus Ljunghia . The mites left bite marks (as illustrated for two Heptathela species in Schwendinger & Ono 2011: figs 67–68) on the carapace and on the proximal part of the chelicerae of both spiders.

Figures

FIGURE 2. Liphistius isan, male (A, F) and female (B) from Phou Asa, Laos; L. laoticus sp. n., female allotype (C), male holotype (D); L. thoranie, male holotype (E). A – B, habitus. C – F, sternum and labium, ventral view.

FIGURE 4. Liphistius laoticus sp. n., male holotype (A – E, I – J), three male paratypes (F – H), four female paratypes (N – Q; N is the “ allotype ”); L. thoranie, male paratype (illustrated in original description; K), holotype (M); L. ochraceus, male from type locality (L). A, distal part of left palp, ventral view. B, same, retrolateral view. C, same, retrodorsal view. D, M, distal part of palpal organ, slightly different ventral view. E – H, palpal organ, distal view. I, tibial apophysis, retrolateral and slightly proximal view. J – L, paracymbium, dorsal view. N – Q, vulva, ventral view. Scale lines 0.5 mm (A – D, M; E – H, J – L; I; N – Q).