The Southeast Asian Pholcus halabala species group (Araneae, Pholcidae): new data from fi eld observations and ultrastructure

1 Alexander Koenig Research Museum of Zoology, Adenauerallee 160, 53113 Bonn, Germany. 2 Department of Biology, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand. 3 Sarawak Museum, Jalan Tun Abang Haji Openg, 93566 Kuching, Sarawak, Malaysia. 4 National Biodiversity Centre, National Parks Board, 1B Cluny Road, Singapore 259598, Singapore. 5 Centre for Research and Consultancy, Unitar International University, Malaysia.


Introduction
on the procursus that is present in the other fi ve species of the core group, and the hairs in the male ocular area are not particularly strong, but it is moved into the core group because (1) it builds the same distinctive web closely attached to the leaf surface as the fi ve other species; (2) webs are provided with facultative silk tufts like in Ph. halabala and Ph. sepaku (otherwise only known in the African genus Smeringopus Simon, 1890; Huber 2012); (3) females carry the egg-sac under the body like Ph. halabala and Ph. sepaku, which is unique among Pholcidae; (4) life specimens have an almost identical distinctive pattern of large whitish to yellowish and black spots on the abdomen, and on the carapace a pair of V-marks; and (5) the procursus is provided with a distinctive retrolateral distal pocket also present in Ph. halabala 41). Preliminary molecular data (A. Valdez-Mondragón, B.A. Figs 1-8. Live specimens, Pholcus halabala Huber, 2011 (1-6) and Ph. ubin Huber,. 1. ♂ from MacRitchie, Singapore. 2. ♂ from Gunung Jerai, Malaysia. 3. ♀ with egg-sac from Gunung Liang, Malaysia. 4. Juvenile in web with silk tufts, Upper Selatar, Singapore. 5. ♀ with egg-sac from Hala Bala, Thailand. 6. ♀ with egg-sac from Ulu Dong, Malaysia. 7-8. ♂ and ♀ from Pulau Ubin, Singapore. Huber & D. Dimitrov unpublished data), including all species of the core group except Ph. sepaku (i.e., also Ph. erawan), strongly support the monophyly of this group. The RMNH has three further species of the core group from Sabah (Fig. 17), but the specimens are poorly preserved and for this reason not formally described here.
In addition to this core group, we include in the Ph. halabala group two further species that were previously part of the Pholcus quinquenotatus group (Ph. sudhami Huber, 2011;Ph. pakse Huber, 2011) as well as two newly described species (Ph. kuhapimuk sp. nov.; Ph. khaolek sp. nov.). Again, preliminary Figs 9-16. Live specimens, Pholcus sabah Huber, 2011 (9-10), Ph. lintang Huber, 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. molecular data (A. Valdez-Mondragón, B.A. Huber & D. Dimitrov unpublished data) strongly support a close relationship of these four species with the core group, and at least Ph. sudhami and Ph. pakse share some morphological similarities with the core group (carapace and abdomen pattern, male eye triads on low humps, large AME, male cheliceral apophyses with modifi ed hairs), but no putative morphological synapomorphy is known that would support this close relationship. The microhabitat of these four species differs from the core group (rocks and tree roots rather than foliage); egg-sacs are carried in front of the body as in typical pholcids; webs were never seen to be provided with silk tufts. In addition, males of Ph. sudhami and Ph. pakse lack stronger hairs in the ocular area, and both species lack the bulbal appendix.
Three species originally assigned to the halabala group are kept in the group simply for the lack of a better solution: Ph. pyu Huber, 2011;Ph. elongatus (Yin & Wang, 1981); and Ph. exceptus Tong & Li, 2009. Data on natural history and ultrastructure are not available for any of them, nor is any of them included in our preliminary molecular analysis (A. Valdez-Mondragón, B.A. Huber & D. Dimitrov unpublished data). We speculate that Ph. pyu may in fact belong to this group, but the other two species are quite certainly misplaced. Pholcus elongatus lacks AME; males in this species have short eye stalks and pointed cheliceral apophyses without modifi ed hairs; females have a long epigynal scape. We speculate that the closest relatives of Ph. elongatus are the Taiwanese species Ph. pingtung Huber & Dimitrov, 2014 and Ph. chengpoi Huber & Dimitrov, 2014 (six eyes; similar cheliceral apophyses; scape directed toward anterior). Pholcus exceptus is a mysterious species with entirely reduced distal cheliceral apophyses.

Natural history
All six species of the core group were observed in the fi eld. At most localities, abundances seemed very low. Surprisingly, several species were partly or exclusively found in degraded forests. All specimens seen during the day were tightly pressed against the undersides of mostly large leaves. Webs consisted mainly of round platforms with a diameter of about 10 cm; most of the platform was closely attached to the leaf surface. Small silk tufts (Figs 4,16) were observed in some webs of three species (Ph. halabala; Ph. erawan; Ph. sepaku), but may occur in other species as well (very few specimens seen in other species). The same applies to the peculiar position in which egg-sacs are held by females: in Ph. halabala, Ph. erawan and Ph. sepaku (and possibly in close relatives), the egg-sac is carried under the prosoma rather than in front of it (Figs 3,(5)(6)16). For further details, see individual species descriptions below.
Three of the four species assigned tentatively to the halabala group based on preliminary molecular data were observed in the fi eld (Ph. kuhapimuk sp. nov.; Ph. khaolek sp. nov.; and Ph. sudhami), and these were mostly found on rocks at cave entrances, with the body fl at on the rock surface. Only Ph. sudhami at Erawan was mostly found on exposed tree roots at the riverside. Webs were either barely visible (a few threads close to the rock surface) or consisted of very delicate small domed sheets attached to the rock (Ph. khaolek sp. nov.). Silk tufts were not seen in any of these webs. Egg-sacs were carried in front of the body as in typical pholcids (Fig. 51).

Diagnosis
Easily distinguished from most other species in halabala core group by simple triangular uncus and short curved appendix with simple rounded tip (fi g. 530 in Huber 2011;Fig. 24), and by distinctive sclerite anteriorly in internal female genitalia (fi g. 533 in Huber 2011; similar in Ph. lintang sp. nov, cf.

Variation
Previously, this species was known only from southern Thailand (type locality) and Sumatra (Huber 2011). Specimens from Sumatra were assigned tentatively because of minor differences in the procursus. The new specimens above support the idea that this is intraspecifi c variation rather than an indication of species limits. First, the ventral distal spine of the procursus varies continuously among localities, with specimens from Singapore having a short spine like specimens from Sumatra, and specimens from Malaysia being intermediate between those from Singapore and Thailand. Most deviating are specimens from Pulau Pinang, where the ventral distal process of the procursus carries three spines instead of only one. Second, the shape of the dorsal process of the procursus varies strongly with the angle at which it is viewed. If the procursus is viewed in slightly dorsal view, the process looks as in the original description (Huber 2011, fi g. 531); if the procursus is viewed in perfect retrolateral view, the process appears slightly wider.
The usual pattern on the carapace consists of two V-marks on the posterior half (Figs 1, 6). In some specimens, these marks are fused into larger marks or even into a single large mark that covers the entire posterior half of the carapace (Fig. 5). Tibia 1 in newly collected specimens: 12 males: 7.0-9.1 (mean 8.0); 6 females: 6.4-7.7 (mean 7.0).

Natural history
Even though this species is widespread, it seemed to be extremely rare at most localities. This explains the low specimen numbers even though it was searched for with considerable effort. At the type locality, three days of intensive search yielded only one female and two juveniles. The ATOL Expedition in 2003 (including several experienced arachnologists using a variety of collecting techniques) also found only one adult specimen. At some localities (Gunung Jerai; Penang), Ph. halabala was found together with Ph. erawan, but Ph. halabala seemed to prefer dicot leaves while Ph. erawan was mostly found on monocot leaves. Otherwise these two species are barely distinguishable in the fi eld. Webs consisted mainly of round platforms attached to the undersides of leaves. Small silk tufts (Fig. 4) were observed in some webs at most localities. Egg-sacs are carried under the prosoma (Figs 3, 5-6).

Etymology
The species name is derived from the type locality; noun in apposition.
COLOR. Carapace ochre-yellow with brown pattern of radiating marks posteriorly, in live specimens with reddish color in median area between posterior marks (Fig. 7); ocular area and clypeus not darkened; sternum with some dark marks posteriorly; legs ochre-yellow with dark brown patellae and tibia-metatarsus joints; abdomen pale ochre-gray with small black and white marks dorsally and laterally, monochromous ventrally. Fig. 7; ocular area slightly raised, with brushes of ~10 stronger hairs behind each PME; carapace without median furrow; clypeus unmodifi ed; sternum wider than long (0.62/0.40), unmodifi ed.  Fig. 31, with pair of frontal apophyses provided with two modifi ed hairs each and rounded lateral processes.

Natural history
All Pulau Ubin specimens were found in a highly degraded patch of forest near park headquarters, while no specimen was found in a well preserved forest about 3.3 km WNW. Most specimens were collected by beating of branches, but some were observed in their fl at resting position on the leaves.

Diagnosis
Easily distinguished from putatively closest known relatives (other species in the halabala core group) by 'double' uncus and large rounded rather than pointed fl ap dorsally on procursus (fi gs 537, 538 in

Note
The color dimorphism observed among females from Poring in the original description also occurs among males: while the single male from Sepilok has the 'usual' pattern of two V-marks (Fig. 10), the newly collected male from Poring has a large black mark covering most of the carapace posteriorly ( Fig. 9). This latter pattern also occurs in one of the three females from Sepilok. In the male it is associated with a slightly darker brown sternum that is only medially and anteriorly light; in the female it is associated with a black sternum. Tibia 1 in two males: 7.1, 8.4; in two females: 7.1, 7.3.

Natural history
Most new specimens were collected relatively close to the ground (approximately 50 cm above the ground). All previously known specimens (1♂, 3♀♀) were collected by canopy fogging (Huber 2011).

Etymology
The species name is derived from the type locality; noun in apposition.
COLOR. Carapace pale ochre-whitish with brown pattern of radiating marks posteriorly; ocular area and clypeus not darkened; sternum whitish with dark lateral margins; legs pale whitish with brown patellae and tibia-metatarsus joints; abdomen pale gray with black and white marks dorsally and laterally, monochromous ventrally.  Fig. 11; ocular area raised, with brushes of ~4 spines on low hump behind each PME; carapace without median furrow; clypeus unmodifi ed; sternum wider than long (0.66/0.50), unmodifi ed. Fig. 36, with pair of frontal apophyses provided with two modifi ed hairs each, rounded lateral processes, and indistinct small frontal proximal humps.

Male (variation)
Tibia 1 in other male: 7.0; this male with slightly more pigment, clypeus with large light brown mark.

Female
In general similar to male ( Fig. 12) but without spines behind PME and eye triads closer together than in male (PME-PME distance: 230 μm). Tibia 1 in 1 female: 6.2. Epigynum mostly weakly sclerotized except for posterior area (Fig. 93); with median 'knob' (Figs 37,94); internal genitalia as in Figs 38 and 95, with roundish pore plates close to each other. Females from Kubah National Park and Niah Cave National Park are assigned tentatively because females in this species group are not easily distinguished externally and no males are available from these localities.

Natural history
At Bako, this species was found on the plateau, in the rather low Kerangas forest. At Kubah, most specimens were taken from large leaves of ornamental plants close to the buildings; only one specimen was found in well-preserved forest.

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

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 (fi g. 1467). Male ocular area with dense brush of stronger hairs, but without spines (

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.

Etymology
The species name is derived from the type locality; noun in apposition.
COLOR. Carapace pale ochre-grey with pair of brown marks posteriorly; ocular area slightly darker, clypeus not darkened; sternum pale grey with narrow dark margins; legs pale ochre-yellow with dark brown patellae and tibia-metatarsus joints; abdomen monochromous pale gray. BODY. Habitus as in Fig. 49; ocular area slightly raised, with slightly stronger hairs behind each PME; carapace without median furrow; clypeus unmodifi ed; sternum wider than long (1.00/0.67), unmodifi ed. Fig. 60, with pair of distal frontal apophyses provided with one or two modifi ed hairs each, pair of rounded lateral processes, and pair of small indistinct proximal frontal humps. PALPS. As in Figs 58-59; coxa unmodifi ed; trochanter with large but weakly sclerotized retrolateroventral apophysis and low retrolateral hump; femur proximally widened on ventral side, with small retrolatero-dorsal apophysis; tarsus with short conical dorsal elongation carrying subdistal tarsal organ; procursus rather simple, ventral 'knee' with distal process; bulb with distinctive small uncus and slender appendix; weakly sclerotized short embolus.

Female
In general similar to male ( Fig. 51) but without stronger hairs behind PME; eye triads closer together than in male (PME-PME distance: 185 μm). Tibia 1 in 7 females: 8.1-9.8 (mean 8.7). Epigynum weakly sclerotized bulging area, only posterior margin more strongly sclerotized, apparently without 'knob', or 'knob' hidden below membranous fl ap (Figs 61, 96-97); internal genitalia as in Figs 62 and 98, with small round pore plates far from each other. The specimens from Thaleban National Park are assigned tentatively because no male specimen is available from this locality.

Natural history
At both localities, specimens were only found on rocks at the cave entrances but not deeper in the caves. The spiders were extremely cryptic, tightly pressed against the rock surface and barely visible even at close distance.

Etymology
The species name is derived from the type locality; noun in apposition.  (76).
COLOR. Carapace pale ochre-yellow with pair of light brown marks posteriorly; ocular area and clypeus not darkened; sternum light brown with lighter marks and dark lateral margins; legs ochre-yellow with dark brown patellae and tibia-metatarsus joints; abdomen monochromous ochre-gray.
BODY. Habitus as in Fig. 53; ocular area slightly raised, with brushes of stronger hairs behind each PME (Figs 68-69); carapace without median furrow; clypeus unmodifi ed; sternum wider than long (0.84/0.52), unmodifi ed. ALS with one widened, one pointed, and six smaller cylindrically shaped spigots of varying sizes (Fig. 78). Fig. 65, with pair of distal frontal apophyses provided with two to three modifi ed (cone-shaped) hairs each (Fig. 70), pair of rounded lateral processes, and pair of small indistinct proximal frontal humps.

Natural history
This species was abundant at the type locality on vertical and slightly overhanging smooth rocks. Specimens were observed tightly pressed against the rock surface, in some cases with a small domed web nearby. When disturbed, the spiders dropped to the ground.

Natural history
At the type locality (Erawan) most specimens were found on the lower surfaces of exposed tree roots at the riverside. At the other localities, specimens were only found on overhanging smooth rocks at the cave entrances (Tham Kaeo; Wat Huai Takaeng) or in the forest (Phraya Nakhon). When disturbed, the spiders dropped to the ground.

Distribution
Known from four localities in central western Thailand (Fig. 57).

Pholcus krabi species group
This species group is newly proposed to include three species previously part of the Very low abundances and/or patchy distributions were observed in all three species. However, most specimens known of Ph. kinabalu were collected by canopy fogging (Huber 2011), suggesting that abundances of at least this species may be different in higher forest strata. Egg-sacs are carried in front of the body (Figs 105, 109) as in typical pholcids. This species group is known from mainland Southeast Asia and Borneo (Fig. 110). The RMNH has an additional species from East Kalimantan (Fig. 110) that is not described here because only a single poorly preserved male specimen is available.  Fig. 114).

Etymology
The species name is derived from the type locality; noun in apposition.
COLOR. Carapace pale ochre to whitish with small dark median mark, ocular area and clypeus with light brown pattern; sternum whitish; palps reddish; legs pale ochre to whitish with brown patellae and tibia-metatarsus joints; abdomen pale gray with very indistinct darker marks dorsally and laterally, monochromous ventrally.

Natural history
At Phanom Bencha, all eight specimens were collected from two bushes close to each other. Two days of intensive search in various parts of the forest did not result in any further specimens. At Khao Sok, all specimens were found in degraded forest close to the park road; none was found in well preserved forest.

Diagnosis
Distinguished from similar species (other species in the Ph. krabi group) by morphology of male palps (Figs 124-125; unique shape of bifi d appendix; shape of uncus; procursus with strong distal ventral sclerite, similar only in Ph. chiangdao) and by distinctive rounded sclerites in internal female genitalia (Fig. 127).

Etymology
The species name is derived from the type locality; noun in apposition.
COLOR. Carapace pale ochre-yellow with light brown median line and V-mark, ocular area and clypeus light brown; sternum whitish; palps orange; legs pale ochre-yellow with darker brown patellae and tibiametatarsus joints; abdomen pale gray with some indistinct marks dorsally.
BODY. Habitus as in Fig. 106; ocular area slightly raised and each triad on short stalk directed laterad; carapace without median furrow; clypeus unmodifi ed; sternum wider than long (0.60/0.52), unmodifi ed. Fig. 126, with large proximal lateral processes and pair of rounded distal apophyses without modifi ed hairs.

Natural history
Three of the four specimens were collected from a single bush. Three days of intensive collecting at the type locality resulted in only one further specimen. The ATOL Expedition in 2003 did not collect this species. The domed webs were easily visible among the vegetation, about 1-1.5 m above the ground.

Diagnosis
Distinguished from similar species (other species in the Ph. krabi group) by morphology of male palps (Figs 129-130; long trochanter apophysis; distinctive shapes of simple round uncus and small appendix; procursus strongly bent dorsad, with distinctive prolatero-ventral pointed process and fringed membranous distal elements) and by unique median sclerite in internal female genitalia visible through cuticle (Figs 132, 140).

Etymology
The species name is derived from the type locality; noun in apposition.
COLOR. Carapace pale whitish to gray with pair of light brown marks, ocular area and clypeus not darkened; sternum whitish; palps orange; legs pale ochre-yellow with dark patellae and tibia-metatarsus joints; abdomen pale gray with some indistinct darker marks dorsally. Fig. 108; ocular area slightly raised and each triad on low hump; carapace without median furrow; clypeus unmodifi ed; sternum wider than long (0.60/0.50), unmodifi ed. Fig. 131, with small proximal processes and pair of rounded distal apophyses without modifi ed hairs. large; procursus strongly bent dorsad, with distinctive prolatero-ventral pointed process and fringed membranous distal elements; bulb with strong proximal sclerite, with small uncus and small appendix, short weakly sclerotized embolus.

Natural history
Of the four webs seen at Poring, three had their apex connected to the underside of a leaf; the fourth (of the only male) was freely suspended among the twigs at about 1.5 m above the ground.

Diagnosis
Distinguished from other species in krabi group by male palpal morphology (triangular appendix provided with scales; rather short pointed trochanter apophysis; fi g. 556 in Huber 2011) and female internal genitalia (large round pore plates far from each other; fi g. 559 in Huber 2011).

Pholcus buatong species group
This species group is newly proposed to include one species previously part of the Ph. halabala group (Ph. satun Huber, 2011), one species previously tentatively assigned to the Pholcus ethagala group (Ph. schwendingeri Huber, 2011), and a newly described species (Ph. buatong Huber, sp. nov.). They share three putative synapomorphies, (1) the complete reduction of distal anterior apophyses on the male chelicerae (Fig. 156); (2) the very distinctive dorsal bulging of the male palpal patella ( Fig. 155; angle between femur and patella ~120-125° rather than ~180° as in typical pholcids); and (3) the large, heavily sclerotized 'knob' on the epigynum (Figs 184, 187, 190). The group is strongly supported by preliminary molecular data (A. Valdez-Mondragón, B.A. Huber & D. Dimitrov unpublished data). Pholcus schwendingeri and Ph. buatong sp. nov. also share a distinctive whitish membranous process retrolatero-distally on the procursus (arrows in Figs 155, 180). Otherwise this group appears rather inhomogeneous: Pholcus schwendingeri males have extremely long eye stalks (Fig. 173) while males of the other two species have short eye stalks (Fig. 155); Pholcus buatong sp. nov. is rock-dwelling while the other two species are leaf litter dwelling; Pholcus satun has small AME, while the other two species lack AME; Pholcus satun males have only one bulbal process (sclerotized embolus), while males of the other two species have a membranous embolus plus an appendix. In all three species, egg-sacs are carried in front of the body (Figs 145, 152) as in typical pholcids. This species group is known from southern Thailand and northern mainland Malaysia (Fig. 153). Huber, sp. nov. urn:lsid:zoobank

Diagnosis
Easily distinguished from known congeners by morphology of male palps (Figs 154-155; unique shape of procursus with transversal sclerotized ridges on retrolateral side and complex processes on prolateral side; slender appendix) and by internal female genitalia (large lateral sclerites; shape and position of pore plates; Figs 158, 186). From most congeners (except putatively closest relatives Ph. satun and Ph. schwendingeri) also by dorsally uniquely widened male palpal patella (Fig. 155) and by large sclerotized 'knob' on female external genitalia (Fig. 184).
COLOR. Carapace pale ochre-grey with light brown posterior mark, ocular area with small median and pair of lateral brown marks; clypeus not darkened; sternum pale gray with small very indistinct darker marks; legs ochre-yellow with darker brown patellae and tibia-metatarsus joints; abdomen ochre-gray with some black and indistinct whitish marks dorsally and laterally, monochromous ventrally.

Natural history
At Buatong Cave, most specimens were found in barely visible domed webs close to the rock surface. Only one specimen had its body tightly pressed against the rock surface. At Khao Phueng Cave, specimens were abundant in the cave entrance area (again in very fi ne webs) but not deeper in the cave.

Diagnosis
Easily distinguished from all known congeners by long sickle-shaped bulbal process and by unique shape of procursus (long, S-shaped, with subdistal ventral pointed process; fi g. 580 in Huber 2011); from other species in the buatong group also by longer than wide female internal genitalia (Fig. 170).

Natural history
At all three localities, the species was fairly abundant in suitable forest patches with large numbers of large dead leaves on the ground. The poorly visible webs were closely attached to the lower leaf surface. The spiders barely reacted to disturbance.

Distribution
Known from three localities in southern Thailand (Fig. 153).

Pholcus andulau species group
This species group is newly proposed to include one species previously included in the Ph. halabala group (Ph. andulau Huber, 2011) and the newly described Ph. lambir Huber, sp. nov. They share three putative synapomorphies: (1) the unique, partly sclerotized embolus with strong sclerotized pointed processes (Figs 200,(209)(210)(211)(212); (2) pointed male cheliceral apophyses directed toward each other and without modifi ed hairs (Figs 202,214); and (3) large unsclerotized 'knob' on female external genitalia directed toward anterior (Figs 203,213). The two species are also otherwise very similar (females are indistinguishable in the fi eld; Ph. lambir sp. nov. males have a darker ocular area than Ph. andulau males) and restricted to a limited geographic area in northern Borneo (Fig. 153). Preliminary molecular data (A. Valdez-Mondragón, B.A. Huber & D. Dimitrov unpublished data) suggest a close relationship with the Panjange nigrifrons group (which is also restricted to Borneo), but we know of no putative morphological synapomorphy that would support this relationship. However, general habitus and coloration are almost identical, and the same is true of web structure and microhabitat: in both groups, the spiders build domed webs among the vegetation, with the apex of the sheet connected to the underside of a leaf. In addition, they hang in their webs under the leaf rather than having their bodies pressed against the leaf, and in both groups, cecidomyiid fl ies were often seen in large numbers hanging in the spider webs. When disturbed, Pholcus andulau and Ph. lambir sp. nov. vibrate vigorously. Egg-sacs are carried in front of the body (Figs 194,196), as in typical pholcids. Huber, 2011 Figs 193-194 Pholcus andulau Huber, 2011: 141-142, fi gs 502-504, 521-522, 570-574 (♂♀).

Etymology
The species name is derived from the type locality; noun in apposition.

Natural history
Spiders were collected from domed webs among the vegetation, at approximately 1-2 m above the ground. The apex of the sheet was connected to the underside of a leaf, but spiders hung in their webs under the leaf rather than having their bodies pressed against the leaf. In some webs, cecidomyiid fl ies were seen and collected in large numbers. When disturbed, the spiders vibrated vigorously. Egg-sacs were carried in front of the body (Fig. 196), as in typical pholcids; they are slightly elongate and contain ~25-30 eggs.

Distribution
Known from two localities in northeastern Sarawak (Fig. 153).

Discussion
An unrevised genus with more than 300 described and probably hundreds of undescribed species like Pholcus is notoriously diffi cult to handle: internal relationships are mostly entirely obscure; decisions whether newly collected specimens represent new species or not are diffi cult or impossible to make; and biological peculiarities cannot be interpreted in an evolutionary context. For more than 200 years, isolated species descriptions were added to Pholcus, not only without any phylogenetic framework, but often even without the chance to compare new species with the most similar 'known' congeners. The result was more akin to a long list of biologically relatively meaningless names than to testable hypotheses about natural groups, species limits, and evolutionary trends within the genus. This was unfortunate not only because it led to synonyms and chaos, but mainly because Pholcus is characterized by numerous biologically interesting phenomena whose evolution will only be understood in the context of a phylogenetic framework. For example, (1) several different kinds of male 'head' modifi cations have evolved within the genus, including spines, hooks, eye stalks, and curiously modifi ed hair brushes (Huber 2011), but the evolution of these structures is barely understood; (2) different Pholcus species appear to specialize in specifi c microhabitats, such as leaf litter, dark and sheltered spaces under logs and rocks, open space among vegetation, undersides of green leaves, and rock surfaces. Shifts among these microhabitats and the potential effects of the underlying evolutionary ecological fl exibility on species diversifi cation remain largely unknown (Dimitrov et al. 2013).
A fi rst major effort to bring structure into the taxonomic chaos of Pholcus was made in Huber (2011). Many 'old' and poorly known species were redescribed; fi rst SEM data were provided for numerous species; and the genus was divided into 29 operational species groups, based partly on synapomorphies derived from a fi rst cladistic analysis, partly on putative synapomorphies not derived from formal analysis, and partly just on similarity and geographic closeness. Obviously, this preliminary analysis was just a fi rst step that requires substantial further refi nement to approximate the true phylogenetic history of the genus. More light could have been shed if the nine taxonomic contributions on Pholcus published since 2011 (mostly on Chinese, Korean, and Vietnamese species) had considered anything beyond pure alpha taxonomy, such as phylogenetic relations, distribution patterns, diversity patterns, evolution of character systems, or any other questions of biological interest. Instead, none of them even attempted to place new species into existing species groups. We do not claim that such purely descriptive work is worthless, but we agree with Darlington (1971: 347) that "describing of scattered new species in poorly known groups is often not useful" and with Mayr & Ashlock (1991: 347) that "isolated description […] divorced from revisional or monographic work is the least desirable form of taxonomic publication". This contribution deals mainly with the Pholcus halabala group, originally considered one of the most problematic (i.e., unnatural or non-monophyletic) species groups in Pholcus. The combination of fi eld observations (web design and structure, microhabitat, egg-sac holding position, life color pattern), ultrastructure (silk spigots, male cheliceral apophyses), and general morphology (abdomen shape) have prompted us to completely rearrange the group and to propose three new species groups. We explicitly point out the remaining gaps that need to be addressed, and highlight a number of potentially useful characters (those listed above) in this and related species groups for future formal cladistic analyses. The fact that some of these characters can only be observed in life specimens in the fi eld underlines the importance of continued and focused fi eld work beyond the "accumulation of dead specimens" (cf. Darlington 1971). Future work should especially focus on the Pholcus quinquenotatus group. Three of the species we newly assign to the Ph. halabala group were originally (Huber 2011) proposed as representatives of the Ph. quinquenotatus group. This leaves three species in the Ph. quinquenotatus group, but fi eld observations (and molecular data) may suggest that at least two of them are also part of the Ph. halabala group (Ph. quinquenotatus Thorell, 1878;Ph. namou Huber, 2011), making the Ph. quinquenotatus group obsolete.