Priscula chapintza Huber, 2023

Huber, Bernhard A., Meng, Guanliang, Dupérré, Nadine, Astrin, Jonas & Herrera, Mauricio, 2023, Andean giants: Priscula spiders from Ecuador, with notes on species groups and egg-sac troglomorphism (Araneae: Pholcidae), European Journal of Taxonomy 909, pp. 1-63 : 34-38

Priscula chapintza Huber sp. nov.

urn:lsid:zoobank.org:act:D8155AE4-4752-4DF4-B3F3-A6BC5C02F01E

Figs 25–28 , 41F , 44 G-H

Diagnosis

Distinguished from known congeners by details of procursus ( Fig. 26A–C ; long ventral distal sclerite slender in lateral view, wide in dorsal view, with simple tip; distinctive dorsal process with bifid tip), genital bulb ( Fig. 26D–F ; main bulbal process with unique prolateral hook), epigynum ( Fig. 28A–B ; shorter than in most known congeners – similar to P. esmeraldas sp. nov.), and female internal genitalia ( Fig. 27C ; almost round pore plates far apart).

Type material

Holotype ECUADOR – Pastaza • ♂; Via Puyo-Macas, Comunidad Chuwitayo 7 km via Comunidad Chapintza, Cueva de los Tallos ; 1.9512° S, 77.7885° W; 640 m a.s.l.; 5 Oct. 2021; E.E. and A.A. Tapia leg.; QCAZ.

Paratypes ECUADOR – Pastaza • 1 ♀, 1 juv., together with holotype; QCAZ • 1 ♂, 1 juv.; same collection data as for holotype; QCAZ • 1 ♂; same locality and date as for holotype; N. Dupérré, E.E. and A.A. Tapia leg.; QCAZ • 1 ♂, 1 ♀; same collection data as for preceding; ZFMK Ar 24095 • 5 ♀♀ (one female used for SEM), 3 juvs; same collection data as for preceding; QCAZ • 1 ♀, 2 juvs; same collection data as for preceding; QCAZ • 1 ♀, 1 juv.; same collection data as for preceding; QCAZ .

Etymology

The species name is derived from the type locality, noun in apposition.

Description

Male (holotype)

MEASUREMENTS. Total body length 3.8, carapace width 2.0. Distance PME–PME 260 µm; diameter PME 150 µm; distance PME–ALE 80 µm; distance AME–AME 40 µm; diameter AME 35 µm. ALE and PLE larger than PME (diameters ALE 200 µm, PLE 190 µm). Leg 1: 49.3 (12.0+ 0.9+12.4 +21.1 + 2.9), tibia 2: 9.3, tibia 3 missing, tibia 4: 8.3; tibia 1 L/d: 62.

COLOR (in ethanol). Carapace whitish, with light brown median band and radial marks, ocular area brown, clypeus light brown; sternum pale ochre with light brown margins; legs whitish, with darker rings subdistally on femora and proximally and subdistally on tibiae; abdomen pale ochre-gray, dorsally and laterally densely covered with black and white marks, ventrally monochromous, very indistinct ochre mark in front of gonopore.

BODY. Habitus similar to P. pastaza (cf. Fig. 6A ). Ocular area raised, without hump on posterior side, with pair of brushes of stronger hairs between ocular triads. Deep thoracic groove. Clypeus unmodified except sclerotized rim. Sternum slightly damaged, unmodified. Abdomen as high as long, dorso-posteriorly rounded.

CHELICERAE. As in Fig. 27A–B , with short entapophyses, pair of slender frontal apophyses in very distal and lateral position, without stridulatory ridges.

PALPS. As in Fig. 25A–C ; coxa unmodified, trochanter with low rounded ventral protrusion, femur large, proximally with distinct retrolateral process followed by deep furrow, ventral rim distally straight (in ventral view) and not protruding; patella ventrally reduced to strongly sclerotized narrow rim; tibia small relative to femur; procursus ( Fig. 26A–C ) with large protruding dorsal whitish element, distally with large prolateral-dorsal band of fringes, distinctive dorsal process with bifid tip, and flat triangular ventral sclerite; genital bulb ( Fig. 26D–F ) with simple proximal sclerite, with distinctive ventral hook on main bulbal process.

LEGS. Without spines; without curved hairs; with few short vertical hairs; retrolateral trichobothrium of tibia 1 at 5%; prolateral trichobothrium present on all leg tibiae; tarsi without regular pseudosegmentation but rather with many indistinct platelets.

Male (variation)

Tibia 1 in three other males: 9.3, 10.8, 11.2. Other males (and most females) without or with very indistinct dark marks on abdomen.

Female

In general similar to male but clypeus rim not sclerotized and brushes of hairs between eye triads much shorter. Tibia 1 in six females: 8.1–8.5 (mean 8.2). ALS with one strongly widened spigot, one pointed spigot, and one large and four small cylindrical spigots; with distinctively sculptured area medially in front of ALS ( Fig. 41F ). Epigynum ( Fig. 28A–B ) main anterior plate trapezoidal, posterior half whitish and protruding; posterior epigynal plate medially divided by whitish area (indistinct) and with wide shallow depression. Internal genitalia ( Figs 27C , 28C–D ) with strong transversal sclerite and pair of roundish pore plates connected to pair of lateral sclerites posteriorly.

Distribution

Known from type locality only, in Pastaza Province, Ecuador ( Fig. 4B ).

Natural history

Cueva de los Tallos is a cave with a sinkhole in the middle (~ 20m × 20m, 50m deep). Five species of Pholcidae were collected at the bottom of the sinkhole. Most of the Pholcidae , presumably all the Priscula specimens, were collected in the sinkhole under or between large to median boulders, a few possibly in the entrance area, also between boulders.

Figures

Fig. 25. Priscula chapintza Huber sp. nov.; male holotype from Cueva de los Tallos, QCAZ; left male palp, prolateral, dorsal, and retrolateral views. Scale line: 0.5 mm.

Fig. 26. Priscula chapintza Huber sp. nov.; male holotype from Cueva de los Tallos, QCAZ. A–C. Left tarsus and procursus, prolateral, dorsal, and retrolateral views; arrow points at distinctive dorsal process; asterisks: whitish protruding area. D–F. Left genital bulb, dorsal, retrolateral, and ventral views; arrow points at distinctive prolateral hook. Abbreviation: vs =ventral sclerite. Scale lines: 0.5 mm.

Fig. 27. Priscula chapintza Huber sp. nov.; paratypes from Cueva de los Tallos, ZFMK Ar 24095 (♂) and QCAZ (♀). A–B. Male chelicerae, frontal and lateral views. C. Cleared female genitalia, dorsal view. Scale lines: 0.5 mm.

Fig. 28. Priscula chapintzaHuber sp. nov.;female paratype from Cuevade los Tallos, QCAZ.A–B. Abdomen, ventral and lateral views. C–D. Cleared genitalia, ventral and dorsal views. Scale lines: 0.5 mm.

Fig. 41. Priscula spp., SEM photographs of female ocular areas and spinnerets. A–B. Ocular areas, frontal views; Priscula pastaza Huber sp. nov. (A) and P. lumbaqui Huber sp. nov. (B). C–E. ALS, P. pastaza (C), P. esmeraldas Huber sp. nov. (D), and P. lumbaqui sp. nov. (E). F–H. Distinctive structures in front of spinnerets (in place of colulus); P. chapintza Huber sp. nov. (F), P. esmeraldas (G), and P. pastaza (H). Scale lines: 100 µm (A–B); 10 µm (C–G); 2 µm (H).

Fig. 44. Priscula spp., SEM photographs of female legs. A–B. Oval plates of unknown function, in Priscula lumbaqui Huber sp. nov. (A, metatarsus 4) and P. pastaza Huber sp. nov. (B, metatarsus 4). C–F. Tarsal claws of leg 1 (C, P. pastaza), leg 2 (D, P. pastaza), leg 3 (E, P. bonita Huber sp. nov.), and leg 4 (F, P. pastaza). G. Microstructure of claw tines (P. chapintza Huber sp. nov.). H. Basis of mechanoreceptive hair (P. chapintza; metatarsus 4), showing distal bulge (on right side). Scale lines: 10 µm.

Fig. 6. Priscula spp., binghamae and andinensis groups, live specimens. A–B. P. pastaza Huber sp. nov.; male and female with egg-sac from Cavernas del Anzu Forest Reserve. C–D. P. bonita Huber sp. nov.; male from La Bonita-Santa Barbara and female with egg-sac from Gruta de los Tayos. E–F. P. lumbaqui Huber sp. nov.; male and female from near Lumbaqui.

Fig. 4. Known distribution of Priscula in Ecuador. A. Representatives of the gularis group. Circles: P. gularis (TL=type locality) and specimens treated herein as “P. gularis?” and “P. cf. gularis”. Squares: other Ecuadorian representatives of the gularis group. B. Representatives of the andinensis group (red) and binghamae group (blue) in Ecuador. The background colors indicate biogeographic regions of Ecuador (as far as relevant for Priscula, i.e., Andean regions from western foothill forests to eastern foothill forests), taken from Torres-Carvajal et al. (2019).