Pholcus tanahrata Huber

Bernard A. Huber, Joseph K. H. Koh, Amir-Ridhwan M. Ghazali, Kamil A. Braima, Olga M. Nuñeza, Charles Leh Moi Ung & Booppa Petcharad, 2016, New leaf- and litter-dwelling species of the genus Pholcus from Southeast Asia (Araneae, Pholcidae), European Journal of Taxonomy 200, pp. 1-45 : 7-9

Pholcus tanahrata Huber sp. nov.

urn:lsid:zoobank.org:act:F930688A-BB3D- 4FEB- 9FCE-3AB42FDF581D

Figs 4–7 , 10–14 , 77 , 81–83

Diagnosis

Easily distinguished from most similar known relatives (other species of the P. ethagala group on the Malay Peninsula) by morphology of male palps ( Figs 10–11 ; procursus with two distinctive dorsal processes, each with bifid tip), and by details of female internal genitalia ( Figs 13, 14 ; pair of anteriorly converging lateral sclerites visible through cuticle; elongate parallel pore plates).

Etymology

The species is named for Tanah Rata, the town close to the type locality; noun in apposition.

Material examined

Holotype

MALAYSIA: ♂, ZFMK ( Ar 15692 ), Pahang, Cameron Highlands (4.460°N, 101.392°E), 1200 m a.s.l., forest along ‘trail 9’, leaf litter, 25 Feb. 2015 (B.A. Huber) ; adult 26 Feb. 2015; fixed 28 Feb. 2015.

Other material

MALAYSIA: 1 ♀, ZFMK, together with holotype ; 1 ♂, ZFMK ( Ar 15693 ), same data, adult 1 Mar. 2015; died while molting; fixed 2 Mar. 2015 ; 4 juvs, in absolute ethanol, ZFMK ( Mal 283 ), same data as holotype .

Description

Male (holotype)

MEASUREMENTS. Total body length 3.9, carapace width 1.05. Leg 1: 38.5 (8.9 + 0.5 + 9.0 + 18.0 + 2.1), tibia 2: 5.4, tibia 3: 3.3, tibia 4: 4.8; tibia 1 L/d: 103. Distance PME-PME 570 µm, diameter PME 125 µm, distance PME-ALE ~35 µm; AME absent.

COLOR. Carapace ochre-yellow with light brown triangular mark posteriorly, ocular area, eye stalks and clypeus light brown, some irregular back pigment in AME area; sternum whitish, labium brown; legs ochre-yellow with darker brown patellae and tibia-metatarsus joints; abdomen ochre-gray with some dark marks dorsally and laterally, monochromous ventrally.

BODY. Habitus as in Figs 4–5 ; ocular area raised, each triad on long stalk ( Fig. 77 ); carapace without median furrow; clypeus unmodified; sternum wider than long (0.76/0.52), unmodified.

CHELICERAE. As in Fig. 12 , with single pair of frontal proximal apophyses directed towards median; without distal modification; without stridulatory ridges.

PALPS. As in Figs 10–11 ; coxa unmodified; trochanter with very long curved retrolatero-ventral apophysis and small weakly sclerotized retrolateral process; femur with indistinct retrolatero-dorsal hump proximally and ventral hump more distally; tarsus with large rounded elongation; procursus complex, proximal part with large ventral ‘knee’ and complex dorsal and prolateral processes; hinged distal part with distinctive flat dorsal process and whitish areas retrolaterally and prolaterally, transparent processes prolaterally; bulb with very large appendix, long slender embolus, with small uncus-like process partly sclerotized as continuation of proximal bulbal sclerite (hidden by bulb in Fig. 10 ).

LEGS. Without spines and curved hairs; few vertical hairs; retrolateral trichobothrium on tibia 1 at 3%; prolateral trichobothrium absent on tibia 1, present on other tibiae; tarsus 1 with apparently>30 pseudosegments, very indistinct except distally.

Male (variation)

Tibia 1 in other male: 9.7; this second male died while molting and is thus very pale; genitalia identical to holotype.

Female

In general similar to male but eye triads not on stalks and much closer together than in male (PME-PME distance: 230 µm); clypeus and ocular area frontally dark brown. Tibia 1 in 1 female: 6.7. Epigynum weakly sclerotized ( Fig. 81 ), ‘knob’ at posterior rim also weakly sclerotized; distinctive internal sclerites converging anteriorly ( Fig. 13 ); internal genitalia as in Figs 14 , 82, 83 .

Natural history

All specimens were found under large dead leaves on the ground. Such leaves were very rare at the type locality, which explains the low number of specimens despite several hours of intensive search.

Distribution

Known from type locality in Malaysia only ( Fig. 1 ).

Figures

Fig. 1. Known distributions of the Pholcus ethagala group (Malay Peninsula and Sumatra; Sri Lankan species not shown), of the P. tambunan group (Borneo) and of the P. domingo group (Philippines).

Figs 2 – 9. Live specimens. 2 – 3. Pholcus phui Huber, 2011, Hala Bala, ♂ and ♀ with egg-sac. 4 – 7. P. tanahrata Huber sp. nov., Cameron Highlands, ♂, penultimate ♂, and ♀. 8 – 9. P. uludong Huber sp. nov., Ulu Dong, ♂ and ♀.

Figs 10 – 14. Pholcus tanahrata Huber sp. nov. (ZFMK, Ar 15692). 10 – 11. Left male palp, prolateral and retrolateral views. 12. Male chelicerae, frontal view. 13 – 14. Cleared female genitalia, ventral and dorsal views. Scale bars: 10 – 11, 13 – 14 = 0.5 mm; 12 = 0.3 mm.

Figs 77 – 80. Male prosomata, frontal views. 77. Pholcus tanahrata Huber sp. nov. 78. P. uludong Huber sp. nov. 79. P. bukittimah Huber sp. nov. 80. P. barisan Huber sp. nov.

Figs 81 – 86. Epigyna, ventral views, and cleared female genitalia, ventral and dorsal views. 81 – 83. Pholcus tanahrata Huber sp. nov. (ZFMK, Ar 15692). 84 – 86. P. uludong Huber sp. nov. (ZFMK, Ar 15696).