Mecolaesthus peckorum Huber, 2000

Huber, Bernhard A. & Villarreal, Osvaldo, 2020, On Venezuelan pholcid spiders (Araneae, Pholcidae), European Journal of Taxonomy 718, pp. 1-317 : 77-79

Mecolaesthus peckorum Huber, 2000

Figs 229–237 , 248–250, 255 , 1042

Mecolaesthus peckorum Huber, 2000: 261 , figs 1038–1039 (♂).

Diagnosis (amendments; see Huber 2000)

Females are easily distinguished from most known congeners by oval epigynum slightly protruding ( Figs 248, 255 ), by internal genitalia with pore plates in almost vertical position and contiguous anteriorly, and by distinctive shape of anterior arc [ Figs 237 , 249–250 , similar in M. tabay Huber, 2000 and in M. cordiformis ( González-Sponga, 2009) ]. Note, however, that the female of M. azulita Huber, 2000 is unknown.

New records

VENEZUELA – Mérida • 1 ♂, 1 ♀, ZFMK (Ar 21878–79), Monte Zerpa , forest above La Hechicera (8.634° N, 71.163° W – 8.639° N, 71.167° W), 2050–2180 m a.s.l., 26 Nov. 2018 (B.A. Huber, O. Villarreal M., N.A. Sánchez G.) • 3 ♂♂, ZFMK (Ar 21880), same locality, 14–21 Jun. 2014 (N. Sánchez, M. Fernández) • 2 ♂♂, ZFMK (Ar 21881), same locality, 30 Mar. 2013 (D. Meta) • 1 ♂, ZFMK (Ar 21882), same locality, 5–12 Apr. 2016 (M. Fernández) • 1 ♂, ZFMK (Ar 21883), El Valle , cloud forest along river (8.703° N, 71.077° W), 2650 m a.s.l., 25 Nov. 2018 (B.A. Huber, O. Villarreal M.) .

Redescription of male (amendments; see Huber 2000)

Measurements (male from Monte Zerpa): carapace width: 1.4; leg 1: 23.1 (5.2 +0.5 +5.5+9.7 +2.2); tibia 2: 3.5, tibia 3: 2.9, tibia 4: 3.5; tibia 1 L/d: 32; distance PME–PME 120 µm; diameter PME 100 µm; distance PME–ALE 100 µm; distance AME–AME 15 µm; diameter AME 30 µm. Carapace mostly light brown, ocular area and anterior lateral margins dark brown, clypeus also dark brown; abdomen pale greenish gray, with dark bluish marks dorsally and laterally, lung plates brown, large dark ochre mark at gonopore area and dark bluish median band behind gonopore. Thoracic furrow shallow but distinct; carapace slightly inflated posteriorly, without median hump. Prolateral trichobothrium present on tibia 1. Coxa 4 unmodified. Chelicerae ( Figs 235–236 ) with several small cone-shaped processes at bases of hairs (more proximal than indicated by arrow in Huber 2000: fig. 1034). Procursus and genital bulb as in Figs 229–234 . Tibia 1 in five males (including the male measured in Huber 2000): 5.2–5.7 (mean 5.4).

Description of female

Females in general similar to males. Legs without dark rings like in males. Epigynum oval plate, slightly protruding, internal arc visible in uncleared specimen ( Figs 248, 255 ). Internal genitalia ( Figs 237 , 249– 250 ) with large pore plates in almost vertical position, converging and contiguous anteriorly; anterior arc with median receptacle. Tibia 1 in one female: 4.1.

Distribution

Known from several neighboring localities in the Venezuelan state Mérida (Fig. 1042). All localities are at about 2050–2650 m a.s.l.

Natural history

This species occurs in close proximity to several very similar and putatively closely related species, i.e., M. mucuy , M. tabay , and M. cornutus . At Monte Zerpa there were no obvious microhabitat differences among these species: all seemed to live in very similar sheltered spaces close to the ground.

Figures

Figs 229–237. Mecolaesthus peckorum Huber, 2000; from Mérida, Monte Zerpa (male, ZFMK Ar 21882; female, ZFMK Ar 21879). 229–231. Left palpal tarsus and procursus, prolateral, dorsal, and retrolateral views. 232–234. Left genital bulb, prolateral, dorsal, and retrolateral views. 235–236. Male chelicerae, frontal and lateral views. 237. Cleared female genitalia, dorsal view. Scale lines: 0.3 mm.

Figs 245–256. Mecolaesthus Simon, 1893; epigyna, ventral and lateral views and cleared female genitalia, ventral and dorsal views. 245–247, 254. M. cornutus Huber, 2000; from Mérida, El Valle (ZFMK Ar 21872). 248–250, 255. M. peckorum Huber, 2000; from Mérida, Monte Zerpa (ZFMK Ar 21879). 251–253, 256. M. mucuy Huber, 2000; from Mérida, Mucuy (type locality; ZFMK Ar 21885).