Chibchea hamadae Huber & Carvalho 2019, sp. n.
Creators: name: Huber, Bernhard A.
name: Carvalho, Leonardo S.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Pholcidae
Chibchea
Chibchea hamadae

description: Chibchea hamadae Huber & Carvalho sp. n.
Figs 152–153, 160, 163, 165, 168, 175–176
Type material. BRAZIL: ♂ holotype, UFMG (22736), 1♂ 3♀ paratypes, UFMG (22051, 22737); 1♂ 2♀ paratypes, CHNUFPI (2522); and 1♂ 1♀ paratypes, ZFMK (Ar 20630), Amazonas, Manaus, Reserva Florestal Adolpho Ducke (2.932°S, 59.970°W), 80 m a.s.l., 5–6.xi.2016 (B.A. Huber, L.S. Carvalho).
Other material examined. BRAZIL: 2♂ 3♀, CHNUFPI (2480, 2485, 2524, 2527, 2531); 4♂ 2♀, UFMG (21861, 22050, 22052, 22614, 22618); and 1 juv., ZFMK (Br16-335), all in pure ethanol, same data as holotype.
Etymology. The species is named for the Brazilian entomologist Neusa Hamada (INPA), in recognition of her help with logistics during our 2016 Amazon expedition.
Diagnosis. Distinguished from most similar known congeners (C. santosi, C. valle, C. amapa) by shapes of procursus and bulbal apophysis (Figs 160, 163; bulbal process without ventral sclerite proximally, with indistinct dorsal membranous process; procursus tip not bifid, wider than in C. santosi), by shape of process proximally on male palpal femur (Fig. 165; similar to C. santosi but with additional rounded process), and by external and internal female genitalia (Figs 168, 175–176; epigynal plate trapezoidal, slightly wider anteriorly than posteriorly, without posterior processes; oval pore plates far apart).
Description. Male (holotype). MEASUREMENTS. Total length 2.25, carapace width 0.85. Distance PME-PME 80 µm; diameter PME 90 µm; distance PME-ALE 60 µm; distance AME-AME 15 µm, diameter AME 20 µm. Leg 1: 19.2 (4.4 + 0.3 + 4.7 + 8.6 + 1.2), tibia 2: 2.9, tibia 3: 2.4, tibia 4: 2.9; tibia 1 L/d: 67.
COLOR (in ethanol). Carapace pale ochre-yellow with indistinct pattern of brown median mark including ocular area and brown lateral marginal bands; clypeus with pair of brown marks below eye triads; sternum brown; legs light brown, tips of tibiae whitish; abdomen pale greenish to blueish gray with blueish marks dorsally and laterally, ventrally with light brown mark in gonopore area and blueish band between gonopore and spinnerets.
BODY. Habitus as in Fig. 152. Ocular area slightly elevated. Thoracic furrow present. Clypeus unmodified. Sternum wider than long (0.58/0.40), unmodified.
CHELICERAE. Very similar to C. amapa (cf. Fig. 156), pair of processes on fangs mostly on posterior side as in C. santosi (cf. Fig. 157; barely visible in frontal view).
PALPS. Very similar to C. amapa (cf. Figs 154–155) but femur with additional prolateral-ventral process and proximal retrolateral-ventral process of different shape (Fig. 165); procursus with simple tip, not bifid (Fig. 160); bulbal process slender, without serrated ventral sclerite, with very indistinct membranous dorsal process (Fig. 163).
LEGS. Without spines and curved hairs, few vertical hairs; retrolateral trichobothrium of tibia 1 at 8%; tibia 1 without prolateral trichobothrium (present on other tibiae); tarsus 1 with ~25 pseudosegments, distally distinct.
Male (variation). Tibia 1 in 7 other males: 4.1–4.4 (mean 4.3); one male (UFMK 22618) with much shorter legs (tibia 1: 3.15). Freshly molted adults (and juveniles) are bright purplish.
Female. In general similar to male (Fig. 153) but cheliceral fangs unmodified. Tibia 1 in 9 females: 2.8–4.3 (mean 3.2). Epigynum anterior plate trapezoidal, slightly wider anteriorly than posteriorly, with distinct rugose area in anterior part (Fig. 175); internal arc visible through cuticle along anterior margin of anterior plate; apparently without pockets; posterior plate simple, weakly sclerotized. Internal genitalia with pair of oval pore plates (Figs 168, 176).
Distribution. Known from type locality in Amazonas state, Brazil, only (Fig. 346).
Natural history. This species was found in tiny webs in small holes in the ground under the leaf litter. It was collected during heavy rainfall and the spiders got immobilized immediately by direct contact with water, which suggests that the spiders depend on spaces in the ground sheltered from water.
description: Published as part of Huber, Bernhard A. & Carvalho, Leonardo S., 2019, Filling the gaps: descriptions of unnamed species included in the latest molecular phylogeny of Pholcidae (Araneae), pp. 1-96 in Zootaxa 4546 (1) on page 49, DOI: 10.11646/zootaxa.4546.1.1, http://zenodo.org/record/2619020