Priscula bonita 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 : 43-48

Priscula bonita Huber sp. nov.

urn:lsid:zoobank.org:act:E8DC917E-0778-4C1B-AA97-F59DB99B3A6A

Figs 6C–D , 33–36 , 42F–G , 44E

Priscula sp. n. ‘Ecu93’ – Dederichs et al. 2022: 46 (sperm ultrastructure).

Diagnosis

Distinguished from known congeners by details of procursus ( Fig. 34A–C ; distinctive distal sclerite with two pointed processes; slender proximal part – similar to P. annulipes (Keyserling, 1877) and P. venezuelana ), genital bulb ( Fig. 34D–F ; main bulbal process longer than in most known congeners, with pointed tip), and female internal genitalia ( Fig. 35C ; pore plates roughly triangular, narrower posteriorly than anteriorly – similar to P. bolivari ). From most known congeners in Ecuador (except P. lumbaqui sp. nov.) also by very large male palpal femur ( Fig. 33C ; 1.7 times longer than palpal tibia; P. lumbaqui : 2.0; other species in Ecuador. 1.1–1.3).

Type material

Holotype ECUADOR – Sucumbíos • ♂; near La Bonita ; 0.474° N, 77.558° W; 1870 m a.s.l.; 1 Oct. 2021; B.A. Huber and M. Herrera leg.; humid forest; MECN–ARAC–41–T .

Paratypes ECUADOR – Sucumbíos • 1 ♂, 1 ♀; same collection data as for holotype; MECN–ARAC–42–T , in ZFMK Ar 24104 .

Other material examined

ECUADOR – Sucumbíos • 1 ♀, 1 juv. (in pure ethanol); same collection data as for holotype; ZFMK Ecu214 • 1 ♂; between La Bonita and Santa Barbara ; 0.6470° N, 77.4910° W; 2720 m a.s.l., 1 Oct. 2021; B.A. Huber and M. Herrera leg.; humid forest; MECN–ARAC–43–T • 1 ♂ (1 palp used for SEM); same collection data as for preceding; MECN–ARAC–44–T , in ZFMK Ar 24105 • 1 ♀, 1 juv. (in pure ethanol); same collection data as for preceding; ZFMK Ecu216 . Napo • 1 ♂, 4 ♀♀ (one female used for SEM); Gruta de Los Tayos , in ‘cave’ (canyon); 0.2186° S, 77.7402° W; 1590 m a.s.l.; 29 Sep. 2021; B.A. Huber and M. Herrera leg.; MECN–ARAC–45–T , in ZFMK Ar 24106–07 • 2 ♀♀, 3 juvs (in pure ethanol); same collection data as for preceding; ZFMK Ecu205 • 1 ♀; Antisana N.P. ; 0.6409° S, 77.8086° W; 2000 m a.s.l.; 28 Sep. 2021; B.A. Huber and M. Herrera leg.; humid forest; MECN–ARAC–46–T , in ZFMK Ar 24108 • 1 ♀, 1 juv. (in pure ethanol); same collection data as for preceding; ZFMK Ecu201 .

Assigned tentatively (see below)

ECUADOR – Napo • 1 ♂ (in pure ethanol); SE Archidona, Rio Hollin ; 0.955° S, 77.748° W; 660 m a.s.l.; 29 Nov. 2009; P. Michalik leg.; ZFMK Mich35 . Pastaza • 1 ♂, 1 ♀ abdomen; Cavernas del Anzu Forest Reserve, at cave entrance of Cueva Copa del Mundo ; 1.4054° S, 78.0433° W; 1140 m a.s.l.; 26 Sep. 2021; B.A. Huber and M. Herrera leg.; MECN–ARAC–47–T , in ZFMK Ar 24109 • 1 ♀ (in pure ethanol; abdomen transferred to ZFMK Ar 24109); same collection data as for preceding; ZFMK Ecu184 • 3 ♀♀ (in pure ethanol); Cavernas del Anzu Forest Reserve ; between 1.406° S, 78.043° W and 1.416° S, 78.049° W; 1140–1270 m a.s.l.; 26 Sep. 2021; B.A. Huber and M. Herrera leg., ZFMK Ecu185 .

Etymology

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

Description

Male (holotype)

MEASUREMENTS. Total body length 5.2, carapace width 2.1. Distance PME–PME 270 µm; diameter PME 170 µm; distance PME–ALE 180 µm; distance AME–AME 45 µm; diameter AME 45 µm. ALE and PLE larger than PME (diameters 250 µm). Leg 1: 46.1 (11.7 +0.9+11.5 + 18.7 +3.3), tibia 2: 8.1, tibia 3: 5.7, tibia 4: 7.3; tibia 1 L/d: 55.

COLOR (in ethanol). Carapace pale ochre-yellow, with large brown median mark and three pairs of lateral marks, ocular area also brown, clypeus with large brown band narrowing towards chelicerae; sternum light brown with thin darker margins; legs pale ochre, with 3–4 variably distinct dark rings on each femur and tibia; abdomen dorsally and laterally densely covered with black marks, with some small white marks in-between, ventrally with large brown mark in front of gonopore and light brown sclerite in front of spinnerets.

BODY. Habitus as in Fig. 6C . Ocular area raised, without hump on posterior side, without comb of stronger hairs at median side of each ocular triad. Deep thoracic groove. Clypeus unmodified except sclerotized rim. Sternum wider than long (1.45/1.00), unmodified. Abdomen slightly higher than long, dorso-posteriorly pointed.

CHELICERAE. As in Fig. 35A–B , with short entapophyses, with pair of very small frontal apophyses near fang joints, whitish lateral area slightly protruding; without stridulatory ridges.

PALPS. As in Fig. 33A–C ; coxa unmodified, trochanter slightly protruding ventrally, femur very large, proximally with distinct retrolateral process and prolateral-ventral ridge, distal ventral rim not protruding; patella ventrally reduced to strongly sclerotized narrow rim; tibia small relative to femur; procursus ( Fig. 34A–C ) slender, proximally with exposed tarsal organ (arrow in Fig. 42F ), distally with prolateral-dorsal band of whitish membranous and fringed elements, with strongly sclerotized distal sclerite apparently moveable against proximal part of procursus; genital bulb ( Fig. 34D–F ) with small proximal sclerite connecting to tarsus, with large whitish area on retrolateral-ventral side, strong and slightly spiraling main bulbal process with subdistal sperm duct opening (arrow in Fig. 42G ) and pointed tip.

LEGS. Without spines; with curved hairs on all tibiae and metatarsi, few weakly curved hairs also on femora; with few short vertical hairs; retrolateral trichobothrium of tibia 1 at 7%; prolateral trichobothrium present on all leg tibiae; tarsi without regular pseudosegmentation but rather with many indistinct platelets.

Male (variation)

Tibia 1 in seven males (incl. holotype): 9.9–12.4 (mean 11.4). Lateral marks on carapace variably separated or connected with each other at carapace margin; sternum sometimes with light marks. Males from southern Napo and Pastaza are very similar but have slightly smaller palps and the distal sclerite on the procursus is slightly narrower in retrolateral view. This is also reflected in the relatively large CO1 distances between the sequenced specimen from Pastaza and the sequenced specimens from Sucumbíos and central to northern Napo (8.1–8.8%). Distances among the Sucumbíos and central to northern Napo specimens are 5.3% or lower.

Female

In general similar to male ( Fig. 6D ) but clypeus rim not sclerotized but with median ochre mark. Ventral sclerite in front of spinnerets variably divided medially or undivided. Tibia 1 in 13 females: 6.1– 7.7 (mean 7.2). 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 (similar to Fig. 41G ). Epigynum ( Fig. 36A–B ) main anterior plate trapezoidal, slightly protruding, posteriorly medially slightly indented; posterior epigynal plate reduced to pair of small lateral sclerites. Females from Pastaza with similar anterior plate but less reduced posterior plate ( Fig. 36E–F ). Internal genitalia ( Figs 35C , 36C–D ) with pair of large pore plates in almost parallel position, narrowing posteriorly.

Distribution

Apparently widely distributed along the eastern Andean slopes of Ecuador ( Fig. 4B ).

Natural history

At the type locality and between La Bonita and Santa Barbara, the spiders were found hidden in deep sheltered spaces at ground level. In Antisana National Park, one specimen was found in thick mosses covering a tree trunk, the second one in a crevice of a rock wall. In the canyon of the Gruta de Los Tayos, the spiders were fairly abundant, usually under small ledges on the rock wall, up to several meters above the ground; no specimens were found in the neighboring forest. In Cavernas del Anzu Forest Reserve, some specimens were found in the entrance areas of caves (whose deeper parts were occupied by P. pastaza ). Others were found in the neighboring forest; among the latter, one female was found in the mosses covering a tree trunk. Two egg sacs had diameters of 3.3 and 4.5 mm, respectively, and contained ~25/ 65 eggs with an egg diameter of 1.00 mm.

Figures

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. 33. Priscula bonita Huber sp. nov.; male paratype from near La Bonita, ZFMK Ar 24104; left male palp, prolateral, dorsal, and retrolateral views. Scale line: 0.5 mm.

Fig. 34. Priscula bonita Huber sp. nov.; male paratype from near La Bonita, ZFMK Ar 24104. A–C. Left tarsus and procursus, prolateral, dorsal, and retrolateral views. D–F. Left genital bulb, dorsal, retrolateral, and ventral views. Abbreviation: ds=distal sclerite. Scale lines: 0.5 mm.

Fig. 35. Priscula bonita Huber sp. nov.; male and female paratypes from near La Bonita, ZFMK Ar 24104. A–B. Male chelicerae, frontal and lateral views. C. Cleared female genitalia, dorsal view. Scale lines: 0.5 mm.

Fig. 36. Priscula bonita Huber sp. nov.; female paratype from near La Bonita, ZFMK Ar 24104 (A–D) and female from Cavernas del Anzu Forest Reserve, ZFMK Ar 24109 (E–F). A–B, E–F. Abdomens, ventral and lateral views; arrows point at sclerite in front of spinnerets. C–D. Cleared genitalia, ventral and dorsal views. Scale lines: 0.5 mm.

Fig. 42. Priscula spp., SEM photographs of male pedipalps. A–C. Tip of left procursus in dorsal view (A) and hair-like processes on its prolateral (B) and retrolateral (C) sides; P. esmeraldas Huber sp. nov. D–E. Tip of left procursus in retrolateral view (D) and hair-like processes in more detail (E); P. pastaza Huber sp. nov. F–G. Left procursus and bulb of P. bonita Huber sp. nov., showing position of tarsal organ (arrow in F) and position of sperm duct opening (arrow in G). H. Sperm duct opening (arrow) on bulbal process in P. pastaza. Scale lines: 100 µm (A, F–G); 10 µm (B–C, E); 20 µm (D, 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. 1; continued in Fig. 2. Relationships of Priscula derived from an unpartitioned analysis of molecular data using IQ-Tree and the ClipKIT kpic-smart-gap trimming strategy. Numbers on the branches are SH-aLRT supports (%). The tree shows only the ingroup. For the complete tree (incl. outgroups), and for clade support using different partitioning and alignment strategies, see Supplementary Figures S1–S3. Photos on the right, from top: Priscula llaviucu Huber sp. nov.; P. espejoi Huber sp. nov.; P. binghamae (Chamberlin, 1916); P. pastaza Huber sp. nov.; P. “Tri18-11”.

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. 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).