Priscula llaviucu 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 : 19-23

Priscula llaviucu Huber sp. nov.

urn:lsid:zoobank.org:act:3010560D-557C-45B0-8455-A4F46A21F6D2

Figs 5C–D , 12–15

Diagnosis

Distinguished from known congeners by details of procursus ( Fig. 13A–C ; simple tip with strong prolateral-dorsal sclerite; without retrolateral process), genital bulb ( Fig. 13D–F ; main bulbal process much smaller than in P. azuay sp. nov., similar to P. espejoi sp. nov.), male chelicerae ( Fig. 14A– B ; frontal apophyses in very proximal position), epigynum ( Fig. 15A–B ; in lateral view without anterior bulge similar to P. azuay but posterior bulge more prominent than in P. azuay ), and female internal genitalia ( Fig. 14C ; pore plates oval, converging anteriorly – similar to P. gularis ). From most congeners (from all known congeners in Ecuador) also distinguished by relatively short legs (male tibia 1 <4× carapace width).

Note

This species is genetically close to several of our “ gularis ?” and “ cf. gularis ” specimens (8.7–9.2%) as well as to P. azuay sp. nov. (9.5%) and two undescribed species (“ P. Ecu5” and “ P. Dup55”: 9.3–9.8%).

Type material

Holotype ECUADOR – Azuay • ♂; Cajas N.P., eastern side of Laguna Llaviucu ; 2.841 –2.844 ° S, 79.144° W; 3160 m a.s.l.; 22 Sep. 2021; B.A. Huber and M. Herrera leg.; humid forest; MECN–ARAC–34–T.

Paratype ECUADOR – Azuay • 1 ♂, together with one female abdomen; same collection data as for holotype; MECN–ARAC–35–T , in ZFMK Ar 24099 .

Other material examined

ECUADOR – Azuay • 2 ♀♀, 3 juvs (in pure ethanol; one female abdomen transferred to ZFMK Ar 24099); same collection data as for holotype; ZFMK Ecu157 • Cañar 1 ♂, together with one female abdomen; S of Zhud , ravine above road; 2.4790° S, 78.9978° W; 2960 m a.s.l.; 22 Sep. 2021; B.A. Huber and M. Herrera leg.; MECN–ARAC–36–T , in ZFMK Ar 24100 • 1 ♀ (in pure ethanol; abdomen transferred to ZFMK Ar 24100); same collection data as for preceding; ZFMK Ecu163 .

Etymology

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

Description

Male (holotype)

MEASUREMENTS. Total body length 5.8, carapace width 2.25. Distance PME–PME 200 µm; diameter PME 175 µm; distance PME–ALE 125 µm; distance AME–AME 40 µm; diameter AME 55 µm. ALE and PLE larger than PME (diameters ALE 230 µm, PLE 250 µm). Leg 1: 27.9 (7.1+0.9 +7.3+10.6 + 2.0), tibia 2: 5.6, tibia 3: 4.1, tibia 4: 5.3; tibia 1 L/d: 32.

COLOR (in ethanol). Carapace pale ochre-yellow, with brown median and lateral marks not connected posteriorly (posterior area whitish), ocular area and clypeus dark ochre to brown; sternum brown with some lighter marks; legs light ochre-brown, with distinct dark rings subdistally on femora and proximally and subdistally on tibiae, further less distinct rings at half lengths of femora and tibiae and proximally on femora (partly only on ventral side); abdomen gray, dorsally and laterally densely covered with black marks and very small white marks in-between, ventrally with distinct brown plate in front of gonopore.

BODY. Habitus as in Fig. 5C . Ocular area raised, with low hump on posterior side, with slightly stronger hairs at median side of each ocular triad. Deep thoracic groove. Clypeus unmodified except sclerotized rim. Sternum wider than long (1.50/1.05), unmodified. Abdomen higher than long, dorso-posteriorly rounded.

CHELICERAE. As in Fig. 14A–B , with short entapophyses, pair of frontal apophyses in very proximal position, without stridulatory ridges.

PALPS. As in Fig. 12A–C ; coxa unmodified, trochanter with low rounded ventral protrusion, femur large, proximally with distinct retrolateral process, distal ventral rim protruding; patella ventrally reduced to strongly sclerotized narrow rim; tibia small relative to femur; procursus ( Fig. 13A–C ) relatively simple, without dorsal whitish or membranous element, distally with strong prolateral-dorsal sclerite and further partly membranous elements; genital bulb ( Fig. 13D–F ) with distinct process on proximal sclerite, with whitish area on retrolateral-ventral side, slightly spiraling main bulbal process with pointed tip.

LEGS. Without spines; with many curved hairs on all tibiae and metatarsi, some weakly curved hairs also on anterior femora; with few short vertical hairs; retrolateral trichobothrium of tibia 1 at 9%; prolateral trichobothrium present on all leg tibiae; tarsi without regular pseudosegmentation but rather with many indistinct platelets.

Male (variation)

Tibia 1 in other male from type locality: 7.4; shape of median mark on carapace slightly variable. Male from near Zhud with slightly longer legs (tibia 1: 8.8), slightly narrower chelicerae (width 0.83 vs 0.87) and slightly more slender cheliceral apophyses (in lateral view), minimally wider distal element of procursus in retrolateral view, slightly narrower sclerite dorsally on genital bulb (arrow in Fig. 13D ), and slightly shorter distal tip of main bulbal process.

Female

In general similar to male ( Fig. 5D ), but clypeus rim not sclerotized, dark rings at half lengths of femora and tibiae more distinct. Tibia 1 in two females from type locality: 5.2, 5.3; in female from near Zhud: 6.0. Epigynum ( Fig. 15A–B ) main anterior plate trapezoidal, very dark, posteriorly bulging; posterior epigynal plate medially divided by whitish area. Internal genitalia ( Figs 14C , 15C–D ) with pair of oval pore plates.

Distribution

Known from two localities in Azuay and Cañar Provinces, Ecuador ( Fig. 4A ).

Natural history

At the type locality, the spiders were found hidden in deep sheltered spaces at ground level. Near Zhud, the two specimens were hidden deeply in a large tussock. One egg-sac had a diameter of 4.3 mm, and contained ~ 50 eggs with an egg diameter of 1.05 mm.

Figures

Fig. 5. Priscula spp., gularis group, live specimens. A–B. P. azuay Huber sp. nov.; male and female from Guayaquil-Cuenca, ‘loc. 2’. C–D. P. llaviucu Huber sp. nov.; male and female with egg-sac from Cajas National Park. E–F. P. cf. gularis; males from near Zhud and from near Baños. G–H. P. espejoi Huber sp. nov.; male and female with egg-sac from Guayaquil-Cuenca, ‘loc. 1’.

Fig. 12. Priscula llaviucu Huber sp. nov.; male paratype from Cajas N.P., ZFMK Ar 24099; left male palp, prolateral, dorsal, and retrolateral views. Scale line: 0.5 mm.

Fig. 13. Priscula llaviucu Huber sp. nov.; male paratype from Cajas N.P., ZFMK Ar 24099. A–C. Left tarsus and procursus, prolateral, dorsal, and retrolateral views; arrows point at distinctive prolateraldorsal sclerite. D–F. Left genital bulb, dorsal, retrolateral, and ventral views; arrow points at sclerite that is narrower in male from near Zhud. Scale lines: 0.5 mm.

Fig. 14. Priscula llaviucu Huber sp. nov.; male paratype and female from Cajas N.P., ZFMK Ar 24099. A–B. Male chelicerae, frontal and lateral views. C. Cleared female genitalia, dorsal view. Scale lines: 0.5 mm.

Fig. 15. Priscula llaviucu Huber sp. nov.; female from Cajas N.P., ZFMK Ar 24099. A–B. Abdomen, ventral and lateral views. C–D. Cleared genitalia, ventral and dorsal views. Scale lines: 0.5 mm.

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).