Carapoia munduruku Huber 2018, sp. n.

Carapoia munduruku sp. n.

Figs 552–553, 564–572, 625–627

Diagnosis. Distinguished from similar congeners (C. fowleri, C. ocaina) by shape of procursus (distinctive bifid tip; Figs 565, 568–570), by armature of male chelicerae (pair of small frontal apophyses set with modified hairs and further patch of modified hairs proximal of apophyses; Figs 566–567), and by female external and internal genitalia (roughly triangular epigynal plate; distinctive median internal sclerite between pore-plates, the latter consisting of many platelets; Figs 571–572, 625–627).

Etymology. The specific name honors the Munduruku, an indigenous people of Brazil traditionally living in the Tapajós river valley; noun in apposition.

Type material. BRAZIL: Pará: ♂ holotype, 1♀ paratype, UFMG (21540–41), and 22♂ 11♀ paratypes, ZFMK (Ar 19225–26), Floresta Nacional de Tapajós, km 83 (3.049°S, 54.928°W), 95 m a.s.l., 14–18.x.2016 (B.A. Huber, L.S. Carvalho).

Other material examined. BRAZIL: Pará: 1♀ 1 juv. in pure ethanol, ZFMK (Br 16-260), same data as types. 3♂ 1♀, ZFMK (Ar 19227), Floresta Nacional de Tapajós, km 67, ‘site 1’ (2.847°S, 54.972°W), 180 m a.s.l., 15.x.2016 (B.A. Huber, L.S. Carvalho). 1♂ 2♀, ZFMK (Ar 19228), Floresta Nacional de Tapajós, km 67, ‘site 2’ (2.875°S, 54.941°W), 190 m a.s.l., 15.x.2016 (B.A. Huber, L.S. Carvalho). 11♂ 4♀, ZFMK (Ar 19229), Floresta Nacional de Tapajós, km 221 (4.046°S, 54.938°W), 80 m a.s.l., 16.x.2016 (B.A. Huber, L.S. Carvalho); 1♂ 1♀ 1 juv. in pure ethanol, ZFMK (Br 16-275), same data. 1♂ 3♀, ZFMK (Ar 19230), Floresta Nacional de Tapajós, km 72, ‘site 1’, near river (2.896°S, 55.064°W), 40 m a.s.l., 17.x.2016 (B.A. Huber, L.S. Carvalho); 1♀ in pure ethanol, ZFMK (Br 16-279), same data. 4♂ 2♀, ZFMK (Ar 19231), Floresta Nacional de Tapajós, km 72, ‘site 2’ (2.940°S, 54.933°W), 140 m a.s.l., 17.x.2016 (B.A. Huber, L.S. Carvalho).

Description. Male (holotype)

MEASUREMENTS. Total body length 4.8, carapace width 1.8. Distance PME-PME 140 µm, diameter PME 130 µm, distance PME-ALE 100 µm, distance AME-AME 25 µm, diameter AME 50 µm. Sternum width/length: 1.1/ 0.65. Leg 1: 52.7 (12.4 + 0.7 + 12.0 + 24.8 + 2.8), tibia 2: 7.1, tibia 3: 5.3, tibia 4: 6.4; tibia 1 L/d: 75. Femora 1–4 width (at half length): 0.30, 0.34, 0.38, 0.33; also tibiae 3 significantly thicker than other tibiae.

COLOR (in ethanol). Carapace pale ochre, with brown lateral margins, brown triangular mark posteriorly, orange-brown mark behind ocular area; ocular area not darkened; clypeus with orange median band; sternum orange; legs brown, without dark rings, tips of femora and tibiae slightly lighter; abdomen pale orange-gray, few internal dark marks laterally, ventrally with brown plate in front of gonopore, long median mark behind gonopore, indistinct large light brown plate in front of spinnerets.

BODY. Habitus as in Fig. 552; ocular area slightly raised; carapace with distinct median furrow; clypeus unmodified; sternum unmodified.

CHELICERAE. As in Figs 566–567, pair of small frontal apophyses set with ~15 modified hairs each and further patch of ~15 modified hairs proximal of apophysis.

PALPS. As in Figs 564–565; coxa with small retrolateral each apophysis; trochanter with small ventral process; femur with large retrolatero-ventral process proximally that is curved towards prolateral at its tip, indistinct dorsal hump; procursus straight, with bifid tip, one branch sclerotized, one membranous; genital bulb with slender curved apophysis, bulbal process with large mostly membranous dorsal protrusion.

LEGS. Without spines, with curved hairs on all tibiae, on femora 1 and 4 (few), and on metatarsi 1 (few), few vertical hairs; retrolateral trichobothrium on tibia 1 at 3.5%; prolateral trichobothrium present on tibia 1; tarsus 1 with ~35 pseudosegments, distally very distinct.

Male (variation). Tibia 1 in 39 other males: 9.9–12.1 (mean 11.3). Some males with fewer curved hairs on legs (e.g., only tibiae 1 and few on tibiae 4). Abdominal pattern variable: sometimes without long median ventral mark, rarely with dark marks also dorsally.

Female. In general similar to male (Fig. 553) but without curved hairs on legs, all femora (and tibiae) approximately same width, and with dark rings on femora (subdistally) and tibiae (proximally and subdistally). Tibia 1 in 24 females: 7.3–9.3 (mean 8.2). Epigynum as in Figs 571, 625; anterior plate roughly triangular, brown, weakly protruding; with pair of diverging sclerites in membrane behind anterior plate; narrow and barely visible posterior plate. Internal genitalia as in Figs 572, 627, with large oval pore-plates consisting of many platelets, distinctive median sclerite between pore-plates.

Natural history. The spiders were very abundant from close to the ground up to about 1 m, juveniles even higher. Webs often appeared unusually ‘dirty’, and consistently had a second, flat sheet of silk under the domed main sheet. Most females had large brown genital plugs (Fig. 626).

Distribution. Known from several sites in Floresta Nacional de Tapajós in Pará state (Brazil) (Fig. 741).