Mecolaesthus trampa Huber 2020, sp. nov.
Creators: name: Huber, Bernhard A.
name: Villarreal, Osvaldo
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Pholcidae
Mecolaesthus
Mecolaesthus trampa

description: Mecolaesthus trampa Huber sp. nov.
urn:lsid:zoobank.org:act: CC180E54-0102-4D0A-9FD3-21EE30ED7698
Figs 427–428, 435–443, 462–464, 1044
Diagnosis
Distinguished from similar congeners (M. grandis group) by armature of male chelicerae (Figs 441– 442; pair of large frontal processes divided into lateral apophysis with 3–5 modified hairs each and frontal ridge with 4–5 modified hairs each; small process more distally, with 3–4 modified hairs each), by shape of main bulbal process (Figs 438–440; distinctive transversal prolateral sclerite), by shape of epigynum (Figs 462–463; triangular plate with pair of additional low sclerotized processes laterally), and by internal female genitalia (Figs 443, 463–464; distinctive pair of anterior processes).
Etymology
The species name refers to the type locality; noun in apposition.
Type material
VENEZUELA – Táchira • ♂ holotype, ZFMK (Ar 21926), SE Pregonero, forest near La Trampa (7.9236° N, 71.7152° W), 1300 m a.s.l., 10 Feb. 2020 (B.A. Huber, O. Villarreal M., Q. Arias C.).
Other material examined
VENEZUELA – Táchira • 2 ♂♂, 3 ♀♀, ZFMK (Ar 21927–28), and 1 ♂, 1 ♀ in pure ethanol, ZFMK (Ven20-122), same collection data as for holotype.
Description
Male (holotype)
MEASUREMENTS. Total body length 3.5, carapace width 1.3. Distance PME–PME 110 µm; diameter PME 120 µm; distance PME–ALE 120 µm; diameter AME 25 µm; distance AME–AME 20 µm. Leg 1: 50.7 (12.0 +0.6+12.1 + 23.1 +2.9), tibia 2: 7.9, tibia 3: 6.0, tibia 4: 6.9; tibia 1–4 diameters: 120 µm, 140 µm, 150 µm, 150 µm; tibia 1 L/d: 101.
COLOR (in ethanol). Carapace pale ochre-gray with wide median dark band and lateral marginal dark bands, ocular area and clypeus also darkened; sternum pale ochre-grey, labium darker brown; legs pale ochre, without darker rings; abdomen pale greenish-gray, dorsally and laterally with dark bluish marks, ventrally with small brown mark in gonopore area, light brown book lung covers, with large median bluish mark; without lateral anterior plates opposing fourth coxae and without plate above pedicel opposing carapace inflation.
BODY. Habitus similar to M. lechosa Huber sp. nov. (cf. Figs 429–430). Ocular area distinctly raised. Carapace anteriorly with distinct thoracic groove, posteriorly slightly inflated. Clypeus unmodified. Sternum wider than long (0.90/0.75). Abdomen slightly elongated, pointed at spinnerets.
CHELICERAE. As in Figs 441–442, with pair of large frontal processes divided into lateral apophysis with 3–5 modified (short conical) hairs each and frontal ridge with 4–5 modified hairs each; with pair of small processes more distally, each with 3–4 modified hairs.
PALPS. In general very similar to putative close relatives [e.g., M. tuberculosus (González-Sponga, 2009); cf. Figs 365–366]; coxa with retrolateral apophysis, trochanter with very small ventral process, femur proximally with large retrolateral process, distally with prominent rounded ventral process, retrolateral trichobothrium of tibia in very distal position; procursus (Figs 435–437) at basis with bifid dorsal process with branches of unequal length, with small retrolateral apophysis, distally with pair of partly membranous processes; genital bulb complex (Figs 438–440), distally mostly membranous/whitish but with distinctive prolateral transversal sclerite (arrows in Figs 438–439).
LEGS. Without spines and curved hairs; few vertical hairs; coxa 4 unmodified; retrolateral trichobothrium of tibia 1 at 3%; prolateral trichobothrium present on all leg tibiae; tarsus 1 with ~40–45 pseudosegments, mostly distinct.
Male (variation)
Tibia 1 in two other males: 10.1, 11.7; other males with indistinct darker rings on leg femora (subdistally).
Female
In general similar to male (Figs 427–428) but without carapace inflation, book lung covers not darkened. Tibia 1 in three females: 8.0, 8.1, 8.1. Epigynum (Fig. 462) relatively small, triangular, anterior margin straight, with pair of low sclerotized posterior processes laterally (arrows in Fig. 463); anterior part of internal receptacle visible in uncleared specimens; without posterior plate. Internal genitalia (Figs 443, 463–464) with pair of distinctive anterior processes arising from sclerite with pore plates, with additional pair of anterior sclerites extending towards lateral and large median receptacle.
Distribution
Known from type locality only, in Venezuela, Táchira (Fig. 1044).
Natural history
Most specimens were collected in sheltered spaces near the ground, in similar webs but less exposed than M. arepa Huber sp. nov. at the same locality.
description: Published as part of Huber, Bernhard A. & Villarreal, Osvaldo, 2020, On Venezuelan pholcid spiders (Araneae, Pholcidae), pp. 1-317 in European Journal of Taxonomy 718 on pages 124-127, DOI: 10.5852/ejt.2020.718.1101, http://zenodo.org/record/4069574