Pholcus matutum 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 : 40-42

Pholcus matutum Huber sp. nov.

urn:lsid:zoobank.org:act:CCCB3C54-30E8-4792-A4AC-F8A3A80DF703

Figs 138–139 , 157–160 , 164–166

Diagnosis

Distinguished from most similar known relative ( P. domingo Huber sp. nov.) by morphology of male palps ( Figs 157–158 ; shorter procursus with longer dorsal process; shorter and more pointed appendix); females of these two species are difficult to separate (internal genitalia relatively longer in P. domingo Huber sp. nov.; compare Figs 144 and 160 ).

Etymology

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

Material examined

Holotype

PHILIPPINES: ♂, ZFMK ( Ar 15729 ), Mindanao, Mt. Matutum , Kawit Forest, ‘site 1’ (6.338°N, 125.104°E), 950 m a.s.l., along brook, on leaf, 13 Feb. 2014 (B.A. Huber, E. Mondejar) .

Other material

PHILIPPINES: 4 ♂♂, 4 ♀♀, 1 juv., ZFMK ( Ar 15730–31 ), and 1 ♂, 1 ♀, MSU-IIT, same data as holotype ; 2 ♀♀, 3 juvs, in absolute ethanol, in ZFMK ( Phi 269 ), same data ; 1 ♀, RMNH, Mindanao, Davao, Mt. Apo Nature Reserve [~ 7.03°N, 125.40°E?], 800 m a.s.l., on wild coffee leaf in secondary forest, 26 Apr. 1982 [R. Deeleman] .

Description

Male (holotype)

MEASUREMENTS. Total body length 4.4, carapace width 0.9. Leg 1: 36.9 (8.8 + 0.4 + 8.8 + 17.3 + 1.6), tibia 2: 5.4, tibia 3: 3.2, tibia 4: 4.6; tibia 1 L/d: 108. Distance PME-PME 260 µm, diameter PME 100×120 µm, distance PME-ALE ~30 µm; distance AME-AME 50 µm, diameter AME 15 µm.

COLOR. Carapace pale ochre, without dark pattern (only small internal medio-posterior structure visible through cuticle), ocular area also dark, clypeus pale ochre, only proximally darker; sternum whitish; legs ochre-yellow with dark brown patellae and tibia-metatarsus joints; abdomen pale ochre-gray with black marks dorsally and laterally, monochromous ventrally except pair of small brown spots in book-lung area.

BODY. Habitus as in Fig. 138 ; ocular area slightly raised, each triad on additional short hump; carapace without median furrow; clypeus unmodified; sternum wider than long (0.60/0.50), unmodified.

CHELICERAE. As in P. domingo Huber sp. nov. (cf. Fig. 142 ), barely modified, with indistinct lateral humps proximally.

PALPS. As in Figs 157–158 ; coxa unmodified; trochanter with very long curved ventral apophysis; femur with ventral and retrolatero-dorsal processes (slightly different shapes than in P. domingo Huber sp. nov.); tibia very large (relative to femur); procursus rather simple, with strong ventral ‘knee’ and distinctive long dorsal process distally; bulb with long semitransparent embolus and large sclerotized process (putative appendix) densely covered with scales on retrolateral surface, with lighter prolateral branch proximally (appendix with more pointed tip than in P. domingo Huber sp. nov.; prolateral branch with more rounded tip).

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>20 pseudosegments, only distally a few fairly distinct.

Male (variation)

Some males with pair of small darker marks posteriorly on carapace (similar to P. domingo Huber sp. nov.). Tibia 1 in 5 other males: 8.3–9.3 (mean 8.7).

Female

In general similar to male ( Fig. 139 ), carapace pattern different: most females with two pairs of light brown to orange marks, one pair near median line posteriorly, one pair laterally; one female with same carapace pattern as P. domingo Huber sp. nov. (posterior half of carapace largely covered by light brown to orange pattern). Eye triads slightly closer together than in males (PME-PME distance: 230 µm). Tibia 1 in 4 females: 6.6, 6.9, 6.9, 7.2. Sternum whitish as is males (not brown as in P. domingo Huber sp. nov. females). Epigynum very simple, weakly sclerotized ( Fig. 164 ), with transverse ridges and finger-shaped posterior ‘knob’ ( Fig. 159 ); internal genitalia as in Figs 160 , 165, 166 .

Natural history

The spiders were found in very fine, barely visible webs tightly attached to the leaf surface of live leaves.

Distribution

Known from two localities in southern Mindanao ( Fig. 1 ). The single female specimen from Epol Falls assigned tentatively to P. domingo Huber sp. nov. might actually belong to this species.

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 131 – 139. Live specimens and dorsal color patterns, Pholcus domingo group. 131 – 137. Pholcus domingo Huber sp. nov., ♂ and ♀ with parasitized egg-sac from Santo Domingo (131 – 132), habitus of ♂♂ from Santo Domingo (133) and Mt. Mupo (134), and carapace dorsal views, ♂ and ♀ from Santo Domingo (135 – 136) and ♂ from Mt. Mupo (137). 138 – 139. P. matutum Huber sp. nov., Mt. Matutum, ♂ and ♀ with egg-sac.

Figs 157 – 160. Pholcus matutum Huber sp. nov. (ZFMK, Ar 15730 – 31). 157 – 158. Left male palp, prolateral and retrolateral views. 159 – 160. Cleared female genitalia, ventral and dorsal views. Scale bars: 157 – 158 = 0.5 mm; 159 – 160 = 0.3 mm.

Figs 161 – 166. Epigyna, ventral views, and cleared female genitalia, ventral and dorsal views. 161 – 163. Pholcus domingo Huber sp. nov. (ZFMK, Ar 15721). 164 – 166. P. matutum Huber sp. nov. (ZFMK, Ar 15731).

Figs 140 – 144. Pholcus domingo Huber sp. nov. (ZFMK, Ar 15720 – 21). 140 – 141. Left male palp, prolateral and retrolateral views. 142. Male chelicerae, frontal view. 143 – 144. Cleared female genitalia, ventral and dorsal views. Scale bars: 140 – 141 = 0.5 mm; 142 – 144 = 0.3 mm.