Micropholcus bukidnon Huber & Meng 2024, sp. nov.
Creators: name: Huber, Bernhard A.
name: Meng, Guanliang
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Pholcidae
Micropholcus
Micropholcus bukidnon

description: Micropholcus bukidnon Huber sp. nov.
Figs 4 H, 5 E, F, 6 H, 8 G, H, 9 E, J, 10 G, H, 11 J, 12 H, 72, 73, 74, 75
Micropholcus Phi 114 – Eberle et al. 2018 (molecular data). Huber et al. 2018: fig. 11.
Micropholcus sp. n. Phi 114 – Huber and Eberle 2021, Suppl. material 1.
Type material.
Holotype. Philippines – Mindanao • ♂; Bukidnon Province, Central Mindanao University, Faculty Hill; 7.852 ° N, 125.048 ° E; 330 m a. s. l.; on rocks in degraded forest; 10 Feb. 2014; B. A. Huber leg.; ZFMK Ar 24694.
Other material.
Philippines – Mindanao • 7 ♂♂, 10 ♀♀, 1 juv. (1 ♂, 1 ♀ used for SEM); same collection data as for holotype; ZFMK Ar 24695 to 24696 • 2 ♂♂, 3 ♀♀, in pure ethanol; same collection data as for holotype; ZFMK Phi 273 • 3 ♂♂, 2 ♀♀; Barangay San Jose, Blue Water Cave; 7.705 ° N, 125.035 ° E; 230 m a. s. l.; at rocks at cave entrance; 16 Feb. 2014; B. A. Huber leg.; ZFMK Ar 24697 • 2 ♂♂, 2 ♀♀, 1 juv., in pure ethanol; same collection data as for preceding; ZFMK Phi 250 • 7 ♀♀; Barangay San Jose, Kabyaw Cave; ~ 7.704 ° N, 125.038 ° E; ~ 260 m a. s. l.; at rocks at cave entrance; 16 Feb. 2014; B. A. Huber leg.; ZFMK Ar 24698.
Diagnosis.
Easily distinguished from known congeners by unusually long proximal frontal apophyses on male chelicerae (Fig. 74 B); by long ventral process of palpal femur (Fig. 72 C); by long rod-shaped putative appendix (Fig. 73 D, E), and by distinctive shapes of processes on procursus (Fig. 73 A – C; in particular large flat dorsal process). Female genitalia very simple externally (Fig. 75 A), distinguished from congeners by absence of external knob (Fig. 10 H) and by distinctive internal structures (round pore plates; m-shaped dorsal arch; concentric ventral arches; distinctive median membranous structures posteriorly).
Description.
Male (holotype). Measurements. Total body length 2.8, carapace width 1.1. Leg 1: 28.1 (6.7 + 0.5 + 7.1 + 12.4 + 1.4), tibia 2: 4.5, tibia 3: 2.9, tibia 4: 3.8; tibia 1 L / d: 77. Distance PME - PME 190 µm, diameter PME 100 µm, distance PME - ALE ~ 30 µm; distance AME - AME 30 µm, diameter AME 15 µm.
Colour (in ethanol). Carapace pale ochre with dark median band widening posteriorly, ocular area and clypeus only slightly darkened; sternum pale ochre with narrow dark margins; legs ochre to light brown, with dark brown patellae and tibia-metatarsus joints; abdomen monochromous pale grey.
Body. Habitus as in Fig. 4 H; ocular area slightly raised (Fig. 5 E); carapace without median furrow; clypeus unmodified; sternum wider than long (0.65 / 0.55), unmodified. Gonopore of scanned male with five epiandrous spigots (Fig. 10 G). Anterior lateral spinnerets with one strongly widened, one pointed, and six cylindrically shaped spigots (Fig. 9 J).
Chelicerae. As in Fig. 74 A, B; proximally with pair of long frontal apophyses and pair of short lateral processes directed towards proximal, distally with pair of dark apophyses near laminae, each provided with five modified (globular) hairs (Fig. 6 H).
Palps. As in Fig. 72; coxa unmodified; trochanter with retrolateral apophysis, tip of apophysis without modified hair (Fig. 9 E); femur with low retrolateral hump proximally and with distinctive ventral process; procursus (Figs 8 G, 73 A – C) very complex distally, with apparently hinged ventral structures and large dorsal flap; genital bulb (Figs 8 H, 73 D, E) with strong proximal sclerite, with long weakly sclerotised embolus and heavily sclerotised cylindrical putative appendix with proximal round protrusion and short subdistal branch.
Legs. Without spines and curved hairs; without sexually dimorphic short vertical hairs; retrolateral trichobothrium on tibia 1 at 10 %; prolateral trichobothrium absent on tibia 1, present on other tibiae; tarsus 1 with ~ 15 pseudosegments, only distally distinct. Tarsus 4 comb-hairs as in Fig. 12 H.
Variation (male). Tibia 1 in nine other males: 5.4–7.3 (mean 6.5); specimens from Barangay San Jose have consistently shorter legs than specimens from Faculty Hill (5.4–5.7 versus 6.6–7.3).
Female. In general similar to male; eye triads at almost same distance (PME - PME: 170 µm; Fig. 5 F). Dark band on carapace in some females posteriorly not widened. Tibia 1 in 19 females: 4.3–6.0 (mean: 5.2). As in males, specimens from Barangay San Jose have consistently shorter legs than specimens from Faculty Hill (4.3–5.2 versus 5.4–6.0). Epigynum very simple (Figs 10 H, 75 A – C), weakly sclerotised, without external ‘ knob’; internal genitalia (Figs 74 C, D, 75 D, E) with round pore plates, m-shaped dorsal arch, concentric ventral arches, and distinctive median membranous structures posteriorly.
Etymology.
The species name is derived from the type locality; noun in apposition.
Distribution.
Known from three localities (two of them very close to each other) in central Mindanao, Philippines (Fig. 13 B).
Natural history.
The spiders were found on rocks, either on the undersides of large rocks with sufficient space to the ground, or in small depressions of near-vertical rock-surfaces (Fig. 14 H). Two egg sacs contained 11 and 25 eggs, respectively, with an egg diameter of 0.54–0.57 mm (Huber and Eberle 2021).
description: Published as part of Huber, Bernhard A. & Meng, Guanliang, 2024, Old World Micropholcus spiders, with first records of acrocerid parasitoids in Pholcidae (Araneae), pp. 95-182 in ZooKeys 1213 on pages 95-182, DOI: 10.3897/zookeys.1213.133178