Carapoia rubra Huber 2018, sp. n.

Carapoia rubra sp. n.

Figs 588–589, 616–624, 635–636

Diagnosis. Easily distinguished from known congeners by shape of procursus (slender in dorsal view, distinctive bifid tip; Figs 620–622), by armature of male chelicerae (pair of diverging frontal apophyses pointing downward; Figs 618–619), and by female external and internal genitalia (roughly round epigynal plate; indistinct sclerites embedded in membrane behind epigynum, connected anteriorly to distinctive round sclerites; oval pore-plates close together and converging anteriorly; Figs 623–624, 635–636).

Etymology. The specific name refers to the red coloration of this species, especially in adult males (Latin ruber, rubra = red); adjective.

Type material. BRAZIL: Pará: ♂ holotype, 1♀ paratype, UFMG (21548–49), and 12♂ 5♀ paratypes, ZFMK (Ar 19253), 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).

Other material examined. BRAZIL: Pará: 1♂ in pure ethanol, ZFMK (Br 16-271), same data as types. 1♂ 2♀, ZFMK (Ar 19254), 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♀ in pure ethanol, ZFMK (Br 16-266), same data.

Description. Male (holotype)

MEASUREMENTS. Total body length 5.3, carapace width 1.8. Distance PME-PME 130 µm, diameter PME 130 µm, distance PME-ALE 90 µm, distance AME-AME 25 µm, diameter AME 45 µm. Sternum width/length: 1.1/ 0.7. Leg 1: 73.1 (18.3 + 0.7 + 16.9 + 34.7 + 2.5), tibia 2: 11.1, tibia 3: 7.9, tibia 4: 9.6; all femora significantly longer than tibiae (e.g., femur 3: 10.2); tibia 1 L/d: 113. Femora 1–4 width (at half length): 0.23, 0.24, 0.25, 0.23.

COLOR (in ethanol). Carapace pale ochre-yellow with brown lateral marginal bands, median line, and mark behind ocular area; ocular area and clypeus without dark marks; sternum ochre yellow except orange mark behind light brown labium; legs dark brown, without dark rings, tips of femora 1 and of all tibiae lighter; abdomen ochreyellow, without internal dark marks, ventrally with indistinct median marks in front of gonopore and in front of spinnerets.

BODY. Habitus as in Fig. 588; ocular area slightly raised; carapace with distinct median furrow; clypeus unmodified; sternum unmodified.

CHELICERAE. As in Figs 618–619, with pair of strong frontal apophyses slightly diverging and pointing straight downward.

PALPS. As in Figs 616–617; coxa with retrolateral apophysis; trochanter with small prolatero-ventral process; femur with large retrolatero-ventral process proximally; tibia relatively long; procursus straight, slender in dorsal view, with bifid tip (Figs 620–622); genital bulb large, with small pointed process (arrow in Fig. 616), long apophysis, large mostly membranous dorsal protrusion, and short transparent ventral process (arrow in Fig. 617).

LEGS. With many short spines on all femora (all sides except dorsal), few spines also proximally on tibiae 2 and 3 (ventrally only); with many curved hairs dorsally on tibiae 1, few vertical hairs; retrolateral trichobothrium on tibia 1 at 2.5%; prolateral trichobothrium present on tibia 1; tarsus 1 with ~35 pseudosegments, quite distinct.

Male (variation). Tibia 1 in 12 other males: 13.3–17.6 (mean 14.7). Smaller males with leg spines restricted to proximal parts of femora (distally gradually replaced by regular short hairs), without spines on tibiae; abdomen in few (small) males with two pairs of lateral/dorsal bands consisting of dark internal marks, and ventral median band behind gonopore.

Female. In general similar to male (Fig. 589), with pair of brown marks on clypeus, internal marks on abdomen usually present and distinct; dark band behind epigynum sometimes present. Spines and curved hairs present in some (large) females only. Tibia 1 in nine females: 9.1–13.7 (mean 11.9). Epigynum as in Figs 623, 635; anterior plate roundish, only weakly protruding; ‘diverging’ sclerites present but poorly developed and rather parallel to each other; posterior plate narrow, light brown. Internal genitalia as in Figs 624, 636, with oval poreplates close together and converging anteriorly, with distinctive round sclerites connected to ‘diverging’ sclerites.

Natural history. The webs of this species reminded of M. aurantiacus, but they were more exposed, sometimes even reached by direct sunlight. This made the red spiders (especially the males) extremely well visible against the dark background of the forest floor.

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