Pholcus lambir Huber

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 (190), pp. 1-55 : 49-53

Pholcus lambir Huber , sp. nov.

urn:lsid:zoobank.org:act:2B969B98-2995-4325-911C-D3013371FFE3

Figs 195–218

Diagnosis

Easily distinguished from putatively closest known relative ( Ph. andulau ) by very short dorsal (slightly prolateral) process on procursus ( Fig. 200 ), by much larger sclerotized teeth on male embolus ( Figs 200 , 209–212 ), and by less curved anterior sclerite in internal female genitalia ( Figs 197–199 ).

Etymology

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

Type material

MALAYSIA-BORNEO: holotype, ♂, ZFMK ( Ar 15059 ), Sarawak, Lambir Hills National Park (4.198– 4.207° N, 114.034– 114.045° E), 60–150 m a.s.l., in domed webs under leaves, 22 Jul. 2014 (B.A. Huber, S.B. Huber) .

Other material examined

MALAYSIA-BORNEO: 9 ♂♂, 13 ♀♀, 1 juv., ZFMK (8 ♂♂, 12 ♀♀, Ar 15060–61 ) and SMK (1 ♂, 1 ♀), same data as holotype ; 1 ♂, 2 ♀♀, in absolute ethanol, ZFMK ( Bor 200 ), same data ; 3 ♂♂, 8 ♀♀, ZFMK ( Ar 15062–63 ), Sarawak, Niah Cave National Park, forest along main trail (3.814– 3.821° N, 113.763– 113.771° E), 20–40 m a.s.l., domed webs under leaves, 27 Jul. 2014 (B.A. Huber, S.B. Huber) .

Description

Male (holotype)

MEASUREMENTS. Total body length 5.0, carapace width 1.05. Leg 1: 48.4 (10.6 + 0.5 + 11.0 + 23.5 + 2.8), tibia 2: 6.9, tibia 3: 4.0, tibia 4: 6.2; tibia 1 L/d: 100. Distance PME-PME 380 µm, diameter PME 100 µm, distance PME-ALE ~40 µm; AME absent (only small irregular internal black marks).

COLOR. Carapace pale ochre-yellow, ocular area and clypeus brown; sternum whitish; legs ochre-yellow to orange, with brown patellae and tibia-metatarsus joints; abdomen ochre-gray with some darker marks dorsally, monochromous ventrally.

BODY. Habitus as in Fig. 195 ; ocular area slightly raised and each triad on short stalk directed obliquely dorsad ( Fig. 205 ); carapace without median furrow; clypeus unmodified; sternum wider than long (0.80/0.65), unmodified. Gonopore with four epiandrous spigots ( Fig. 216 ). ALS with one widened, one pointed, and six smaller cylindrically shaped spigots of varying sizes ( Fig. 218 ).

CHELICERAE. As in Fig. 202 , with distinctive pair of pointed frontal apophyses directed toward each other ( Fig. 214 ); indistinct lateral processes.

PALPS. As in Figs 200–201 ; coxa unmodified; trochanter with retrolatero-ventral apophysis; femur with distinctive ventral process directed proximad; procursus relatively simple, with small semitransparent prolateral process ( Figs 207–209 ) and distinctive sclerotized and membranous distal elements; bulb large, with strong proximal sclerite, with uncus, with proximally heavily sclerotized embolus provided with strong teeth ( Figs 209–212 ).

LEGS. Without spines and curved hairs; few vertical hairs; retrolateral trichobothrium on tibia 1 at 2%; prolateral trichobothrium absent on tibia 1, present on other tibiae; tarsus 1 pseudosegments very indistinct, only distally a few visible in dissecting microscope. Tarsus 4 comb-hairs of the simplified Pholcus - type (cf. Huber & Fleckenstein 2008), with four lateral tines ( Fig. 215 ).

Male (variation)

Tibia 1 in 9 other males: 9.6–11.7 (mean 10.5).

Female

In general similar to male ( Fig. 196 ), but eye triads on low humps and closer together ( Fig. 206 ; PME-PME distance: 200 µm), clypeus darker than in males. Tibia 1 in 20 females: 6.8–8.8 (mean 8.0). Epigynum weakly sclerotized flat plate with large unsclerotized ‘knob’ directed toward anterior ( Fig. 213 ), anterior internal sclerite visible through cuticle ( Figs 197–198 , 203 ); internal genitalia as in Figs 199 and 204 . ALS as in male ( Fig. 217 ).

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 flies 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 ).

Figures

Fig. 153. Known distributions of the Pholcus buatong species group (Malay Peninsula) and of the Pholcus andulau species group (northern Borneo).

Figs 193 – 199. Live specimens, Pholcus andulau group, and female genitalia of Ph. lambir Huber, sp. nov. 193 – 194. Pholcus andulau Huber, 2011, ♂ and ♀ with egg-sac from Gunung Mulu, Sarawak. 195 – 196. Ph. lambir sp. nov., ♂ and ♀ with egg-sac from Lambir, Sarawak. 197 – 199. Ph. lambir sp. nov., female genitalia, untreated in ventral view, cleared in ventral and dorsal views.

Figs 200 – 204. Pholcus lambir Huber, sp. nov., ZFMK Ar 15060 – 61. 200 – 201. Left male palp, prolateral and retrolateral views. 202. Male chelicerae, frontal view. 203 – 204. Cleared female genitalia, ventral and dorsal views. Abbreviations: b = genital bulb; e = embolus; p = procursus; u = uncus. Scale lines: 0.3 mm (202 – 204), 0.5 mm (200 – 201).

Figs 205 – 210. Pholcus lambir Huber, sp. nov., ZFMK Ar 15060 – 61. 205 – 206. Male and female prosomata, frontal views. 207. Right procursus, retrolateral (slightly dorsal) view. 208. Left procursus (and genital bulb), prolateral view. 209. Right procursus (and embolus sclerite), distal view. 210. Right embolus sclerite, prolateral view. Abbreviations: b = genital bulb; e = embolus; p = procursus. Scale lines: 50 µm (210); 100 µm (207 – 209); 200 µm (205 – 206).

Figs 211 – 218. Pholcus lambir Huber, sp. nov., ZFMK Ar 15060 – 61. 211 – 212. Left bulbal processes, prolateral (slightly distal) and ventral views (arrows point at sperm duct opening). 213. Epigynum, ventral view. 214. Distal male cheliceral apophyses. 215. Comb-hairs on male tarsus 4. 216. Male gonopore. 217 – 218. Female and male ALS. Abbreviations: e = embolus; u = uncus. Scale lines: 10 µm (215, 218); 20 µm (217); 30 µm (214, 216); 60 µm (211); 80 µm (212); 200 µm (213).