Pholcus erawan Huber, 2011

Berhard A. Huber, Booppa Petchard, Charles Leh Moi Ung, Joseph K. H. Koh & Amir R. M. Ghazali, 2016, The Southeast Asian Pholcus halabala species group (Araneae, Pholcidae): new data from field observations and ultrastructure, European Journal of Taxonomy 190, pp. 1-55 : 15-17

Pholcus erawan Huber, 2011

Figs 13–16 , 39–48

Pholcus erawan Huber, 2011: 297 –298, figs 1374–1375, 1404–1405, 1466–1470 (♂♀).

Diagnosis

Easily distinguished from putatively closest known relatives (other species in the halabala core group) by absence of dorsal flap on procursus, by long whitish process of male palpal tarsus (fig. 1467 in Huber 2011), by unique shapes of bulbal processes (fig. 1644 in Huber 2011), and by much longer than wide female internal genitalia and small oval pore plates (fig. 1470 in Huber 201 1).

New material examined

THAILAND: 8 ♂♂, 9 ♀♀, ZFMK (7 ♂♂, 8 ♀♀, AR 15016–17 ) and PSUZC (1 ♂, 1 ♀), Kanchanaburi, Erawan National Park (14°22.2' N, 99°08.75' E), 85 m a.s.l., forest along stream, on leaves, 15 Mar. 2015 (B.A. Huber, B. Petcharad) ; 2 ♂♂, 7 ♀♀, in absolute ethanol, ZFMK ( Mal 378 ), same data ; 1 ♂, 1 ♀, ZFMK ( Ar 15018 ), Nakhon Si Thammarat, Khao Nan National Park (8°46.2' N, 98°48.1' E), 250–300 m a.s.l., on leaves in forest, 9 Mar. 2015 (B.A. Huber, B. Petcharad) ; 1 ♂, ZFMK ( Ar 15019 ), same data, collected penultimate, adult on 11 Mar. 2015 ; 3 juvs, in absolute ethanol, ZFMK ( Mal 345 ), same data ; 3 ♂♂, 3 ♀♀, ZFMK ( Ar 15020 ), Nakhon Si Thammarat, Khao Nan National Park (8°46.23' N, 98°48.27' E), 100 m a.s.l., on palm leaves near park buildings, 9 Mar. 2015 (B.A. Huber, B. Petcharad) ; 1 ♂, ZFMK ( Ar 15021 ), same data, collected penultimate, adult on 12 Mar. 2015 ; 2 ♂♂, ZFMK ( Ar 15022 ), Krabi , Khao Phanom Bencha National Park, trails near headquarters (8°14.1' N, 98°55.1' E), 150–300 m a.s.l., on leaves, 8 Mar. 2015 (B.A. Huber, B. Petcharad) ; 4 ♀♀, 4 juvs, in absolute ethanol, ZFMK ( Mal 340 ), same data .

MALAYSIA: 2 ♂♂, 5 ♀♀, ZFMK ( Ar 15023 ), Kedah, Gunung Jerai, forest near Sri Perigi Waterfall (5°48.3' N, 100°24.6' E), 100–200 m a.s.l., on leaves, 27 Feb. 2015 (B.A. Huber) ; 1 ♀, 6 juvs, in absolute ethanol, ZFMK ( Mal 291 ), same data ; 4 ♂♂, 3 ♀♀, 1 juv., ZFMK ( Ar 15024 ), Pulau Pinang, Penang National Park near Teluk Bahang (5°27.7' N, 100°12.1' E), 10–50 m a.s.l., on leaves, 28 Feb. 2015 (B.A. Huber) ; 1 ♂, ZFMK ( Ar 15025 ), same data, collected penultimate, adult on 2 Mar. 2015 ; 1 ♂, 1 ♀, 1 juv., in absolute ethanol, ZFMK ( Mal 296 ), same data .

Description – amendments

Carapace pattern slightly variable, ranging from two separate V-marks ( Fig. 15 ) to medially fused V-marks to almost completely fused single posterior mark ( Fig. 14 ). Females and juveniles with more delicate V-marks. Sternum coloration also slightly variable, from almost monochromous whitish to small black posterior marks (males) and larger black posterior marks (females). Tibia 1 in 21 males: 6.3–8.1 (mean 7.1); in 20 females: 5.8–6.7 (mean 6.3). In most males, except those from the type locality ( Erawan ), the ventro-distal sclerite of the procursus is slightly more pointed than illustrated in Huber 2011 (fig. 1467). Male ocular area with dense brush of stronger hairs, but without spines ( Fig. 43 ); tarsus 4 comb-hairs of the simplified Pholcus - type (cf. Huber & Fleckenstein 2008), with three lateral tines ( Fig. 46 ); procursus with retrolateral distal pocket ( Fig. 41 ); distal male cheliceral apophyses with two cone-shaped teeth (modified hairs) each ( Fig. 39 ); gonopore with four epiandrous spigots ( Fig. 44 ); ALS with one widened, one pointed, and six smaller cylindrically shaped spigots of varying sizes ( Fig. 45 ; pointed spigot damaged in this spinneret).

Natural history

As noted above, Ph. erawan was sometimes found at the same localities as Ph. halabala but on monocot rather than dicot leaves. Only at Erawan , this species seemed to occur on all kinds of leaves, preferably (but not only) large ones. At Khao Nan, Ph. erawan was found on palm leaves both in the forest and in the garden near the park buildings. At Penang, specimens were found both on green leaves and on dead brown leaves still attached to the plant. Small silk tufts were observed in the webs at most localities. At night (at Erawan ), spiders were observed moving among the vegetation.

Distribution

Widely distributed on the Malay Peninsula, reaching northern Laos ( Fig. 17 ).

Figures

Fig. 17. Known distribution of the core group of the Pholcus halabala species group.

Figs 9 – 16. Live specimens, Pholcus sabah Huber, 2011 (9 – 10), Ph. lintang Huber, sp. nov. (11 – 12) and Ph. erawan Huber, 2011 (13 – 16). 9. ♂ from Poring, Sabah. 10. ♂ from Sepilok, Sabah. 11 – 12. ♂ and ♀ from Bako, Sarawak. 13. ♂ from Khao Nan, Thailand. 14. Male from Erawan, Thailand. 15 – 16. ♂ and ♀ with egg-sac from Gunung Jerai, Malaysia.

Figs 39 – 48. Pholcus erawan Huber, 2011, ZFMK Ar 15016 – 17. 39. Male distal cheliceral apophysis (arrows point at modified hairs). 40. Left procursus, prolateral view. 41. Right procursus, retrolatero-dorsal view (arrow points at distal pocket). 42. Left bulbal processes, distal view. 43. Male ocular area, frontal view. 44. Male gonopore. 45. Female ALS. 46. Comb-hairs on male tarsus 4. 47. Female prosoma, frontal view. 48. Epigynum, ventral view. Abbreviations: a = appendix; e = embolus; u = uncus. Scale lines: 10 µm (39); 20 µm (45 – 46); 40 µm (44); 60 µm (42); 80 µm (40); 100 µm (41, 48); 200 µm (43, 47).