Mecolaesthus yerbatero 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 yerbatero

description: Mecolaesthus yerbatero Huber sp. nov.
urn:lsid:zoobank.org:act: 69C90207-D2BA-4DA2-9F06-54A7AC298AF4
Figs 554–555, 560–568, 576–578, 1045
Diagnosis
Easily distinguished from similar pale leaf-dwelling Venezuelan pholcids (Mecolaesthus fallax Huber sp. nov.; Systenita prasina Simon, 1893; Metagonia spp.) by presence of AME, by distinctive pair of apophyses distally on male chelicerae (Figs 566–567; directed towards median), by shape of simple procursus with bifid tip (Figs 560–562), and by epigynum and female internal genitalia (Figs 568, 576– 578): slightly longer than wide weakly sclerotized plate; tube-like internal structure ending at posterior margin of plate (arrow in Fig. 568); distinctive position of pore plates.
Etymology
Named for “Yerbatero” of Colombian singer-songwriter Juanes, in which the protagonist has remedies to offer for almost any suffering; noun in apposition.
Type material VENEZUELA – Mérida • ♂ holotype, ZFMK (Ar 21949), between Mérida and Barinas, ‘site 2’
(8.8645° N, 70.6182° W), 1650 m a.s.l., 27 Nov. 2018 (B.A. Huber, O. Villarreal M.).
Other material
VENEZUELA – Mérida • 2 ♂♂, 1 ♀, 3 juvs, ZFMK (Ar 21950), and 1 ♀, 6 juvs in pure ethanol, ZFMK (Ven18-235), same collection data as for holotype.
Description
Male (holotype)
MEASUREMENTS. Total body length 2.6, carapace width 1.0. Distance PME–PME 130 µm; diameter PME 80 µm; distance PME–ALE 70 µm; distance AME–AME 35 µm; diameter AME 20 µm. Leg 1: 37.2 (8.9 +0.5 +8.9+16.0 + 2.9), tibia 2: 5.3, tibia 3: 3.9, tibia 4: 4.8; tibia 1 L/d: 89.
COLOR (in ethanol). Carapace pale ochre-gray (with greenish internal mark in live specimens), with thin dark median line; ocular area with light brown V-mark; clypeus light brown; sternum whitish; palps ochre-yellow (reddish in live specimens); legs ochre-yellow, with dark rings on tibiae proximally and subdistally, femur 1 proximally darkened; abdomen pale greenish gray, with few darker bluish marks dorsally, monochromous ventrally.
BODY. Habitus as in Fig. 554. Ocular area slightly raised. Carapace very weakly inflated posteriorly, with shallow thoracic groove in anterior part. Clypeus unmodified. Sternum wider than long (0.80/0.55), unmodified. Abdomen slightly elongated, widest in posterior third, pointed at spinnerets.
CHELICERAE. As in Figs 566–567, with pair of proximal anterior humps provided distally with transversal ridges, and distinctive pair of distal apophyses directed towards median.
PALPS. In general similar to M. guasacaca Huber sp. nov. (cf. Figs 534–535) but trochanter with larger ventral process and femur proximally with lower retrolateral process; procursus (Figs 560–562) simple, proximally with indistinct dorsal process, distally with bifid tip; genital bulb (Figs 563–565) with large distal process mostly membranous.
LEGS. Without spines and curved hairs; few vertical hairs; retrolateral trichobothrium of tibia 1 at 2.5%; prolateral trichobothrium present on all leg tibiae; tarsus 1 with ~45 pseudosegments, mostly distinct.
Male (variation)
Tibia 1 in two other males: 9.0, 9.2.
Female
In general similar to male (Fig. 555) but paler (recently molted?), entire prosoma whitish, femur 1 proximally not darkened. Tibia 1 in two females: 5.4, 6.0. Epigynum (Fig. 576) weakly sclerotized, slightly longer than wide, posteriorly weakly bulging, internal structures partly visible in uncleared specimens. Internal genitalia (Figs 568, 577–578) with tube-like structure ending at posterior margin of epigynal plate (arrow in Fig. 568); distinctive position of pore plates; anterior ‘valve’ with median receptacle.
Distribution
Known from type locality only, in Venezuela, Mérida (Fig. 1045).
Natural history
The spiders were found in a forest along a mountain stream. Their slightly domed sheet webs were attached to the undersides of leaves ~ 0.5–1.5 m above the ground, with the spider resting in the apex of the dome directly under the leaf. Most specimens were found in a ‘regular’ position, i.e., ventral side of abdomen facing upwards; one specimen was found in an inverted resting position (abdomen dorsal side upwards).
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 153-155, DOI: 10.5852/ejt.2020.718.1101, http://zenodo.org/record/4069574