Mesabolivar constrictus

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: 115

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-C606-FFF7-2A9C-9EE537B37E46

treatment provided by

Plazi

scientific name

Mesabolivar constrictus
status

sp. n.

Mesabolivar constrictus  sp. n.

Figs 454–456View FIGURES 447–458, 498–505View FIGURES 498–505, 532View FIGURES 520–537

Diagnosis. Easily distinguished from most congeners (except M. saci  ) by subdistal constriction of male chelicerae ( Fig. 498View FIGURES 498–505); also by details of male palp (procursus S-shaped in dorsal view, Fig. 499View FIGURES 498–505; femur very large relative to tibia; cf. Fig. 490View FIGURES 489–493), and by shape of epigynum ( Figs 501–504View FIGURES 498–505; anterior plate with pair of large processes, median pocket, and small median anterior process); from the very similar M. saci  by tip of procursus in frontal view (compare Figs 491View FIGURES 489–493, 499View FIGURES 498–505), by absence of proximal anterior processes on male chelicerae (compare Figs 493View FIGURES 489–493, 500View FIGURES 498–505), and by pair of epigynal processes strongly bent backwards (compare Figs 495View FIGURES 494–497, 504View FIGURES 498–505).

Etymology. The specific name refers to the unusual constriction in the male chelicerae (Latin constrictus  = compressed, squeezed, contracted); adjective.

Type material. BRAZIL: Santa Catarina: ♂ holotype, 1♀ paratype, UFMGAbout UFMG (21534–35), 3♂ 4♀ paratypes, ZFMKAbout ZFMK (Ar 19208), Três Barras National Forest (26.242°S, 50.301°W), 800 m a.s.l., 14.x.2014 (B.A. Huber, L.S. Carvalho).

Other material examined. BRAZIL: Santa Catarina: 5♀ in pure ethanol, ZFMKAbout ZFMK (Br14-146), same data as types. 

Description. Male (holotype)

MEASUREMENTS. Total body length 1.8, carapace width 0.87. Distance PME-PME 80 µm, diameter PME 80 µm, distance PME-ALE 60 µm, distance AME-AME 20 µm, diameter AME 25 µm. Sternum width/length: 0.67/ 0.47. Leg 1: 8.8 (2.0 + 0.3 + 2.1 + 3.0 + 0.7), tibia 2: 1.4, tibia 3: 1.1, tibia 4: 2.1; tibia 1 L/d: 23. Femora 1–4 width (at half length): 0.18, 0.24, 0.24, 0.17.

COLOR (in ethanol). Prosoma and legs ochre-yellow, legs without light or dark rings; abdomen dorsally and laterally densely covered with dark bluish marks, ventrally pale greenish gray with light brown marks in front of gonopore and in front of spinnerets.

BODY. Habitus as in Fig. 454View FIGURES 447–458; ocular area raised; carapace with shallow but distinct median furrow; clypeus unmodified; sternum unmodified.

CHELICERAE. With pair of strong frontal processes and distinctive subdistal constriction ( Figs 498, 500View FIGURES 498–505).

PALPS. In general very similar to M. saci  (cf. Figs 489–490View FIGURES 489–493); only procursus in dorsal view clearly different ( Fig. 499View FIGURES 498–505).

LEGS. Without spines and curved hairs, few vertical hairs; retrolateral trichobothrium on tibia 1 at 8.5%; prolateral trichobothrium present on tibia 1; tarsus 1 with ~15 pseudosegments, distally fairly distinct.

Male (variation). Tibia 1 in three other males: 2.0, 2.1, 2.1. One male with whitish abdomen ( Fig. 455View FIGURES 447–458).

Female. In general similar to male. Tibia 1 in five females: 1.6–1.9 (mean 1.8). Epigynum as in Figs 501–504View FIGURES 498–505; complex anterior plate with small anterior median process, median pocket, and pair of large processes strongly bent backwards; posterior plate anteriorly raised. Internal genitalia as in Figs 505View FIGURES 498–505, 532View FIGURES 520–537, very small relative to external genitalia, with pair of round pore-plates close together.

Natural history. The spiders were found in relatively humid places under logs and branches on the ground, in tiny webs built in small holes in the ground. One egg sac contained ~ 10 eggs.

Distribution. Known from type locality in Santa Catarina state ( Brazil) only ( Fig. 739View FIGURES 738–739).

UFMG

Universidade Federal de Minas Gerais

ZFMK

Zoologisches Forschungsmuseum Alexander Koenig

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Araneae

Family

Pholcidae

Genus

Mesabolivar