Mesabolivar turvo Huber 2018, sp. n.

Mesabolivar turvo sp. n.

Figs 466–469, 538–544

Diagnosis. Distinguished from known congeners by shape of procursus (Figs 539–540; slender with pointed tip), by armature of male chelicerae (Figs 541–542; pair of frontal apophyses not close to median line), and shape of epigynum and internal female genitalia (Figs 543–544; oval anterior plate without pocket and processes; very large posterior plate; distinctive internal structure connecting pore-plates).

Etymology. The specific name is derived from the type locality; noun in apposition.

Type material. BRAZIL: Rio Grande do Sul: ♂ holotype, 1♀ paratype, UFMG (21538–39), 2♂ 4♀ paratypes, ZFMK (Ar 19222), Turvo National Park, Lagoas Trail near headquarters (27.231°S, 53.849°W), 400 m a.s.l., 29.x.2014 (B.A. Huber, L.S. Carvalho).

Other material examined. BRAZIL: Rio Grande do Sul: 3♀ in pure ethanol, ZFMK (Br 14-199), same data as types. 1♀, ZFMK (Ar 19223), Turvo National Park, near Salto do Yucumã (27.136°S, 53.882°W), 175 m a.s.l., 28.x.2014 (B.A. Huber, L.S. Carvalho).

Paraná: 1♂ 1♀, ZFMK (Ar 19224), Iratí Forest Reserve (25.362°S, 50.584°W), 850 m a.s.l., 13.x.2014 (B.A. Huber, L.S. Carvalho); 2♀ in pure ethanol, ZFMK (Br14-145).

Description. Male (holotype)

MEASUREMENTS. Total body length 2.4, carapace width 1.0. Distance PME-PME 110 µm, diameter PME 90 µm, distance PME-ALE 70 µm, distance AME-AME 20 µm, diameter AME 30 µm. Sternum width/length: 0.75/ 0.50. Leg 1: 23.6 (6.0 + 0.4 + 6.1 + 9.5 + 1.6), tibia 2: 3.6, tibia 3: 2.4, tibia 4: 4.1; tibia 1 L/d: 76. Femora 1–4 width (at half length): 0.11, 0.21, 0.17, 0.12.

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

BODY. Habitus as in Figs 466–467; ocular area raised; carapace with shallow but distinct median furrow; clypeus unmodified; sternum unmodified.

CHELICERAE. With pair of strong frontal apophyses, tips of apophyses apparently with one modified hair each (Figs 541–542).

PALPS. As in Figs 538–539; coxa with large retrolateral apophysis; trochanter barely modified; femur with retrolateral process proximally, distally widening; tibia very short; tarsus with two retrolatero-dorsal processes; procursus very simple, without processes, slender with pointed tip, in dorsal view slightly S-shaped (Fig. 540); genital bulb with large process mostly whitish.

LEGS. Without spines and curved hairs, few vertical hairs; retrolateral trichobothrium on tibia 1 at 4%; prolateral trichobothrium present on tibia 1; tarsus 1 with>20 pseudosegments, distally fairly distinct.

Male (variation). Tibia 1 in three other males: 5.8, 5.8 (Turvo National Park), 4.8 (Iratí Forest Reserve).

Female. In general similar to male (Figs 468–469) but femora 2 and 3 not thicker than others. Tibia 1 in six females from Turvo National Park: 3.8–4.4 (mean 4.0); in three females from Iratí Forest Reserve: 3.4, 3.7, 3.7. Epigynum as in Fig. 543; simple oval anterior plate, slightly protruding, internal sclerite visible through cuticle; posterior plate very large, simple, with dark internal mark medially. Internal genitalia as in Fig. 544, with distinctive sclerite connecting pore-plates.

Natural history. The spiders were found in small cavities in the ground, often in the more humid places under dead branches. When disturbed, they ran a short distance and then stopped moving or vibrated very slightly.

Distribution. Known from two localities in Rio Grande do Sul and Paraná states (Brazil) (Fig. 738).