Carapoia tenuis, Huber, 2018

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 : 132-136

Carapoia tenuis sp. n.

Figs 581 , 601–607 , 628–630

Diagnosis. Easily distinguished from known congeners by shape of procursus (very slender in lateral view, distinctive bifid tip; Figs 602–603 ), by bulbal processes (strong apophysis, large dorsal protrusion; Fig. 601 ), by armature of male chelicerae (pair of strongly curved frontal apophyses; Figs 604–605 ), and by female external and internal genitalia (trapezoidal epigynum with whitish central area; small elongated pore-plates; Figs 606–607 , 628– 630 ).

Etymology. The specific name refers to the slender abdomen of this species (Latin tenuis = slender); adjective.

Type material. BRAZIL: Pará: ♂ holotype, 1♀ paratype, UFMG (21544–45), and 4♂ 3♀ paratypes, ZFMK (Ar 19239), 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 16-257), same data as types . 4♂ 1♀, ZFMK (Ar 19240), 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) ; 2♀ in pure ethanol, ZFMK (Br 16-265), same data . 3♀, ZFMK (Ar 19241), 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) . 1♂ 4♀ 1 juv., ZFMK (Ar 19242), 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) . 4♂ 3♀, ZFMK (Ar 19243), 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♀ in pure ethanol, ZFMK (Br 16- 274), same data .

Description. Male (holotype)

MEASUREMENTS. Total body length 3.8, carapace width 1.5. Distance PME-PME 140 µm, diameter PME 120 µm, distance PME-ALE 100 µm, distance AME-AME 35 µm, diameter AME 30 µm. Sternum width/length: 1.0/ 0.66. Leg 1: 56.5 (14.3 + 0.7 + 12.9 + 26.3 + 2.3), tibia 2: 7.7, tibia 3: 5.7, tibia 4: 7.3; all femora significantly longer than tibiae (e.g., femur 3: 7.7); tibia 1 L/d: 103. Femora 1–4 width (at half length): 0.21, 0.21, 0.24, 0.20.

COLOR (in ethanol). Carapace pale ochre-yellow with brown median band with transversal element and lateral marginal bands, ocular area not dark, clypeus with light brown mark near rim; sternum pale ochre to whitish, labium brown; legs dark brown, without dark rings, tips of femora 1 (only!) and of all tibiae lighter; abdomen pale ochre-brown, many internal dark marks dorsally and laterally arranged in bands, ventrally with long median mark behind gonopore.

BODY. Habitus similar to C. kaxinawa (cf. Figs 582–583 ); ocular area slightly raised; carapace with distinct median furrow; clypeus unmodified; sternum unmodified.

CHELICERAE. As in Figs 604–605 , with pair of strongly curved frontal apophyses.

PALPS. As in Figs 601–602 ; coxa with retrolateral apophysis; trochanter with small prolatero-ventral process; femur with large retrolatero-ventral process proximally with small sclerite pointing towards prolateral; tibia relatively long; procursus straight, very slender in lateral view, with bifid tip ( Fig. 603 ); genital bulb very large, with rugose process (arrow in Fig. 601 ), with strong apophysis, large mostly membranous dorsal protrusion, short transparent ventral process (arrow in Fig. 602 ).

LEGS. With many short spines on all femora (all sides except dorsal), few spines also proximally on tibiae 3 (ventrally only); with many curved hairs on tibiae 1 (all sides), few vertical hairs; retrolateral trichobothrium on tibia 1 at 2%; prolateral trichobothrium present on tibia 1; tarsus 1 with ~35 pseudosegments, quite distinct.

Male (variation). Tibia 1 in 11 other males: 10.5–12.8 (mean 11.5). Smaller males with leg spines restricted to proximal parts of femora (distally gradually replaced by regular short hairs).

Female. In general similar to male ( Fig. 581 ) but without leg spines and curved hairs. Tibia 1 in 12 females: 7.9–9.9 (mean 8.6). Epigynum as in Figs 606 , 628 ; anterior plate trapezoidal with whitish central area, weakly protruding in anterior and posterior thirds; diverging sclerites apparently present but poorly developed and barely visible in most specimens; posterior plate barely visible. Internal genitalia as in Figs 607 , 630 , with small elongated pore-plates.

Natural history. The spiders built their domed webs close to the ground (approximately 10–20 cm above ground level), exposed rather than hidden under leaves or other objects. Some females had large bipartite genital plugs ( Fig. 629 ).

Distribution. Known from several sites in Floresta Nacional de Tapajós in Pará state ( Brazil) ( Fig. 742 ).

Figures

FIGURE 742. Known distribution of the Carapoia cambridgei group.

FIGURES 581–589. Live specimens, Carapoia cambridgei group (part 1). 581. C. tenuis sp. n., female from Tapajós. 582– 584. C. kaxinawa sp. n., males and female from Fazenda Colorado. 585–587. C. cambridgei (Mello-Leitão, 1947), males and female from Marabá.588–589. C. rubra sp. n., male and female from Tapajós.

FIGURES 601–607. Carapoia tenuis sp. n. (ZFMK Ar 19239). 601–602. Left male palp, prolateral and retrolateral views (arrows point at rugose process and at transparent ventral process of bulb). 603. Left procursus, dorsal view. 604–605. Male chelicerae, lateral and frontal views. 606. Epigynum, ventral view. 607. Cleared female genitalia, dorsal view. Scale lines: 0.5 (601–602, 604–607), 0.2 (603).

FIGURES625–636. Femaleepigyna inventral views andcleared femalegenitalia indorsal views, Carapoiaparaguaensis and C.cambridgei groups.625–627.C.mundurukusp.n., without andwith plug (arrow)(ZFMK Ar19226).628–630.C.tenuis sp. n., without and with plug (arrow) (ZFMK Ar 19239).631–632.C. tapajossp. n. (ZFMK Ar 19237).633–634.C.kaxinawa sp. n. (ZFMK Ar 19245). 635–636.C. rubra sp. n. (ZFMK Ar 19253).