A new genus of ground and litter-dwelling pholcine spiders from Sarawak (Araneae, Pholcidae)

Two small, ground and litter-dwelling pholcid species from northern Borneo are described as representatives of a new genus, Hantu gen. nov.: H. kapit gen. et sp. nov. and H. niah gen. et sp. nov. Previous cladistic analyses suggested a closer relationship with the genera Savarna Huber, 2005 and Khorata Huber, 2005 (mainland Southeast Asia) than with the geographically closer genus Aetana Huber, 2005 (Borneo and Philippines to Fiji). Since the two species do not share any of the synapomorphies of Khorata and Savarna while having several synapomorphies on their own (ventral apophysis on male palpal coxa; male palpal trochanter apophysis with small teeth or scales; spines on male femora 1; high density of vertical hairs on male femora; presence of scape on epigynum), they are here proposed as representing a new genus.


Introduction
The two species newly described herein were initially to be included in a revision of the Southeast Asian pholcid genus Aetana Huber, 2005(Huber et al. 2015a. Superfi cially, they resembled ground and litter-dwelling representatives of that genus, and their geographic origin also pointed towards Aetana (ranging from Borneo and the Philippines to Fiji) rather than to other similar genera on the Southeast Asian mainland (Savarna Huber, 2005;Khorata Huber, 2005). However, closer examination and cladistic analyses revealed that these two species (under the names "Gen.n. Bor80" and "Gen.n. Bor20" in Huber et al. 2015a) were not only different from Aetana in many details, but, in fact, closer to Khorata and Savarna. At the same time, the two species do not share any of the distinctive characters of Khorata (Huber 2005b) and Savarna (Huber 2005b;Huber et al. 2015b). As a consequence, they are here described as representatives of a new genus.

Material and methods
The material studied herein was collected during a recent expedition to northern Borneo (Jul.-Aug. 2014). It is currently deposited at the Zoologisches Forschungsmuseum Alexander Koenig, Bonn (ZFMK), and the Sarawak Museum, Kuching (SMK).

R e s e a r c h a r t i c l e
urn:lsid:zoobank.org:pub:B73C6A06-1245-41CB-9175-C33BC2273245 Methods and terminology are as in recent revisions (Huber 2011(Huber , 2013. Measurements are in mm unless otherwise noted. Eye measurements are ± 5 μm. Epigyna were cleared in warm NaOH solution and stained with chlorazol black. For SEM photos, specimens were dried in HMDS (Brown 1993), and photographed with a Hitachi S-2460 scanning electron microscope. SEM data are presented within the descriptions, but are not based on the holotype specimens described. The distribution map was generated with ArcMap 10.0. The following abbreviations are used in the text: ALE = anterior lateral eyes ALS = anterior lateral spinnerets AME = anterior median eyes a.s.l. = above sea level L/d = length/diameter PME = posterior median eyes Further abbreviations used only in fi gures are explained directly in the fi gure legends.

Type species
Hantu kapit gen. et sp. nov.

Monophyly and relationships
In a recent morphological cladistic analysis of Aetana and putatively close relatives (Huber et al. 2015a), the monophyly of Hantu gen. nov. was consistently supported by fi ve synapomorphies: (1) presence of ventral apophysis on male palpal coxa (

Natural history
Both species were found in small protected spaces close to the ground (in small holes; among and under rocks, logs, and large leaves) where they build their domed webs.

Composition
Only the two species newly described below.

Etymology
The species name is derived from the type locality; noun in apposition.
COLOR. Carapace pale ochre with large dark lateral marks and median mark posteriorly, dark median line, ocular area and clypeus dark brown. Sternum dark brown to black. Legs ochre to light brown, without dark rings. Abdomen ochre-grey with large dorsal and lateral marks; ventral side largely covered by large dark mark and smaller dark mark at spinnerets.  Fig. 1; ocular area highly modifi ed (Figs 10, 14, 15, 17), with two pairs of large horns arising from near PME and PLE and pair of smaller processes arising from near ALE; each triad on short stalk directed toward lateral; carapace with distinct thoracic furrow; clypeus with small median European Journal of Taxonomy 186: 1-15 (2016) process (Figs 15,17); sternum wider than long (0.60/0.50), unmodifi ed. Chelicerae as in Fig. 11, with pair of proximal lateral apophyses in rather frontal position and pair of small, distal apophyses near lamellae; without modifi ed hairs. Figs 8-9, coxa with sclerotized protruding rim ventro-distally; trochanter with distinctive long retrolateral apophysis widening distally and provided with small teeth at tip (Fig. 16); femur large, HUBER B.A., New spider genus from Sarawak without processes; patella unusually long; tibia long and slender. Procursus highly complex, apparently with several hinges between distinctive sclerites. Bulb simple, weakly sclerotized embolus with subdistal branch.

Natural history
The spiders were found in domed webs in small holes in the ground along a river in well-preserved forest.

Distribution
Known from type locality near Kapit only (Fig. 7).

Diagnosis
Easily distinguished from H. kapit gen. et sp. nov. by absence of horns in male ocular area (Fig. 31), by highly distinctive male palp (Figs 26-27; square-shaped trochanter apophysis; dorsal process on procursus), by strong distal apophyses on male chelicerae (Fig. 28), and by scape on epigynum (Figs 29, 43) more sclerotized and without fi ne transversal folds. From other putatively close relatives in the genera Khorata and Savarna by male procursus shape (dorsal process) and epigynal scape.

MALAYSIA
COLOR. Carapace light ochre with narrow lateral dark margins and large median dark mark including ocular area. Clypeus not darkened. Sternum dark brown. Legs ochre to light brown, without dark rings. Abdomen grey with large dorsal and lateral marks; ventrally with three large dark marks (in genital area, at spinnerets, and in-between).
BODY. Habitus as in Figs 3-4; ocular area slightly raised, each triad on short stalk directed toward lateral (Fig. 31); carapace with shallow but distinct thoracic furrow; clypeus unmodifi ed; sternum wider than long (0.65/0.55), unmodifi ed. Chelicerae as in Fig. 28, with pair of proximal lateral apophyses and pair of strong distal apophyses curved toward median line; without modifi ed hairs. PALPS. As in Figs 26-27, coxa with sclerotized protruding rim ventro-distally; trochanter with short but very large, square-shaped ventral apophysis with very small teeth distally; femur very large, without processes; patella unusually long; tibia long and slender. Procursus very long; with distinctive dorsal process and complex tip. Bulb oval, with simple weakly sclerotized embolus.
LEGS. With single ventral row of ~10 spines on femora 1; without curved hairs; with short vertical hairs in two dorsal rows on all femora and tibiae; retrolateral trichobothrium on tibia 1 at 7.5%; prolateral trichobothrium absent on tibia 1, present on other tibiae. Tarsus 1 pseudosegments indistinct, only distally ~20 visible in dissecting microscope.

Male (variation)
Tibia 1 in 8 other males: 4.8-5.3 (mean 5.0). Margins of carapace sometimes not dark; dorsal pattern on abdomen sometimes indistinct. Number and thickness of spines on femora variable, from few barely thicker hairs (small males) to ~20 distinct spines (large males).

Natural history
The spiders were found close to the ground in small domed webs among and under rocks, under dead leaves, and in little cavities. They were extremely effi cient at escaping through the closed hand, then dropped to the ground and remained motionless, becoming essentially invisible.

Discussion
Pholcid spiders are widely known for their long-legged representatives, some of which are synanthropic, but a large number of species in a range of genera are actually relatively short-legged ground and litterdwellers. About half of all currently recognized genera either include or consist entirely of such shortlegged species (e.g., Huber 2005aHuber , 2005bHuber , 2011Huber , 2013Huber , 2015Huber et al. 2005). This suggests multiple convergent shifts among microhabitats; in fact, molecular data support the notion that such shifts have occurred repeatedly in various directions (Huber et al. 2010;Dimitrov et al. 2013; see also Huber & Dimitrov 2014).
Ground and litter-dwelling pholcids share a similar habitus to a degree that allows reasonable predictions even for museum specimens without microhabitat information. They are small (body size ~1-3 mm), relatively short legged (leg 1 length < 30 mm), rather dark (brown), and have a globular or oval abdomen. This combination seems to be extremely rare in pholcids living in other microhabitats. The only apparent exception known to me are West and Central African representatives of the genus Anansus Huber, 2007 that were collected by canopy fogging (Huber 2007).