Mesabolivar pallens

Huber, Bernhard A., 2018, The South American spider genera Mesabolivar and Carapoia (Araneae, Pholcidae): new species and a framework for redrawing generic limits, Zootaxa 4395 (1), pp. 1-178: 66-68

publication ID

https://doi.org/10.11646/zootaxa.4395.1.1

publication LSID

lsid:zoobank.org:pub:B43C234D-45C4-4A6D-9836-8A7524A5B291

persistent identifier

http://treatment.plazi.org/id/160AC713-C635-FFC6-2A9C-9BA630537B01

treatment provided by

Plazi

scientific name

Mesabolivar pallens
status

sp. n.

Mesabolivar pallens  sp. n.

Figs 266–270View FIGURES266–270, 272View FIGURES 271–279, 294–295View FIGURES 292–305

Diagnosis. Easily distinguished from most known congeners by pale coloration, cylindrical abdomen, and relatively small male palps and epigynum. From most similar congener ( M. kathrinae  ) by wider procursus (compare Figs 272 and 273View FIGURES 271–279), presence of proximal processes on male chelicerae ( Fig. 268View FIGURES266–270), and by presence of median pocket on epigynum ( Figs 269View FIGURES266–270, 294View FIGURES 292–305). Females are externally barely distinguishable from M. brasiliensis  and M. azureus  ; males of these two species have very different procursi (compare Figs 271, 272, 274–279View FIGURES 271–279).

Etymology. The specific name refers to the pale greenish coloration of this species (Latin pallens  = pale, greenish); adjective.

Type material. BRAZIL: Espírito Santo: ♂ holotype, 1♀ paratype, MNRJAbout MNRJ (14316), 1♂ 2♀ paratypes, ZFMKAbout ZFMK (Ar 19093), Vargem Alta, Fazenda Monte Verde (20°27.6’–28.2’S, 40°59.5’– 41°00.2’W), 1000–1200 m a.s.l., 2– 3.x.2010 (B.A. Huber, A. Pérez-González).

Other material examined. BRAZIL: Espírito Santo: 1♂ 1♀ in pure ethanol, ZFMKAbout ZFMK (Br10-84), same data as types. 

Description. Male (holotype)

MEASUREMENTS. Total body length 3.3, carapace width 1.1. Distance PME-PME 120 µm, diameter PME 90 µm, distance PME-ALE 80 µm, distance AME-AME 30 µm, diameter AME 40 µm. Sternum width/length: 0.75/ 0.55. Leg 1: 46.8 (12.7 + 0.4 + 10.1 + 20.9 + 2.7), tibia 2: 6.9, tibia 3: 5.3, tibia 4: 6.7; tibia 1 L/d: 75. Femora 1–4 width (at half length): 0.15, 0.18 (distal third: 0.22), 0.15, 0.14.

COLOR (in ethanol). Carapace ochre-yellow, with indistinct darker mark behind ocular area; ocular area and clypeus not darkened; sternum light brown to orange; legs light to dark brown, with distinct black rings on femora (subdistally) and tibiae (proximally and subdistally), tips of femora and tibiae whitish; abdomen greenish gray, without dorsal pattern, ventrally with light brown plate in front of gonopore and indistinct darker median band behind gonopore.

BODY. Similar to M. azureus  (cf. Fig. 254View FIGURES 253–260); ocular area slightly raised; carapace with shallow but distinct median furrow; clypeus and sternum unmodified.

CHELICERAE. As in Fig. 268View FIGURES266–270, with pair of simple distal apophyses close to median line and pair of small proximal processes.

PALPS. As in Figs 266–267View FIGURES266–270; very small relative to body size; coxa with large retrolateral apophysis; trochanter barely modified; femur long, with retrolateral process proximally, widened distally; tarsus with small dorsal process; procursus strongly bent, with distinctive distal black spine and retrolateral membranous process with small tines ( Fig. 272View FIGURES 271–279); bulb with weakly sclerotized conical process, without side branch.

LEGS. Without spines and curved hairs, few vertical hairs; retrolateral trichobothrium on tibia 1 at 2%; prolateral trichobothrium present on tibia 1; tarsus 1 with ~50 pseudosegments, fairly distinct.

Male (variation). Tibia 1 in two other males: 10.0, 10.5.

Female. In general similar to male. Tibia 1 in four females: 7.7, 7.9, 8.0, 8.5. Epigynum very small and simple, weakly sclerotized, with small median pocket, internal blueish to greenish ‘valve’ visible through cuticle; posterior plate simple ( Figs 269View FIGURES266–270, 294View FIGURES 292–305). Internal genitalia as in Figs 270View FIGURES266–270, 295View FIGURES 292–305, with round pore-plates embedded in large sclerite.

Natural history. The spiders were found in strongly domed webs freely suspended among the vegetation.

Distribution. Known from type locality only ( Fig. 730View FIGURES 730–731).

MNRJ

Museu Nacional/Universidade Federal de Rio de Janeiro

ZFMK

Zoologisches Forschungsmuseum Alexander Koenig

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Pholcidae

Genus

Mesabolivar