Nerudia trigo, Huber & Meng & Král & Ávila Herrera & Izquierdo & Carvalho, 2023

Huber, Bernhard A., Meng, Guanliang, Král, Jiří, Ávila Herrera, Ivalú M., Izquierdo, Matias A. & Carvalho, Leonardo S., 2023, High and dry: integrative taxonomy of the Andean spider genus Nerudia (Araneae: Pholcidae), Zoological Journal of the Linnean Society 198, pp. 534-591 : 560-562

NERUDIA TRIGO HUBER SP. NOV.

( FIGS 1E , 22–24 )

Z o o b a n k r e g i s t r a t i o n: u r n: l s i d: z o o b a n k. org:act: 2D2F4A08-7C18-4ED6-8894-FE391F17E6C6.

Diagnosis: Easily distinguished from known congeners by male chelicerae ( Fig. 22G, H ; without frontal apophyses, with patches of strong hairs); also by shapes of procursus ( Fig. 22A–C ; similar to N. guirnalda , but without prolateral–ventral ridge proximally), by bulbal processes ( Fig. 22D–F ; ventral apophysis distally slender, curved towards ventral, same length as embolar process), and by epigynum and female internal genitalia ( Figs 22I , 23 ; epigynal plate with short but wide posterior indentation, laterally strongly sclerotized; internal genitalia with indistinct ‘receptacle’.

Type material: ARGENTINA – Salta: • ♂ holotype; between Alemanía and Cafayate; 25.7023° S, 65.7022° W; 1340 m a.s.l.; 23 Mar. 2019; B. A. Huber and M. A. Izquierdo leg.; LABRE-Ar 589 • 1 ♂, 2 ♀♀, paratypes; same data as holotype; ZFMK Ar 23894 .

Other material examined: ARGENTINA – Salta: • 10 ♀♀, 2 juvs, in pure ethanol (one female used for SEM; three female prosomata used for molecular study); same data as holotype; ZFMK Arg 206 • 3 ♂♂; same data as holotype; LABRE-Ar 539 • 1 ♂; ~ 1 km SW Alemanía; 25.6300° S, 65.6180° W; 1210 m a.s.l.; 23 Mar. 2019; B. A. Huber and M. A. Izquierdo leg.; ZFMK Ar 23895 • 1 ♀, in pure ethanol; same data as preceding; ZFMK Arg 202 • 2 ♀♀, 1 juv., in pure ethanol; same data as preceding; LABRE-Ar 550 .

Etymology: The species epithet trigo (Spanish for ‘wheat’) is taken from Pablo Neruda’s poem ‘Cien sonetos de amor’; noun in apposition.

Description

Male (holotype). Measurements: Total body length 1.70, carapace width 0.77. Distance PME–PME 80 µm; diameter PME 65 µm; distance PME–ALE 20 µm; distance AME–AME 20 µm; diameter AME 50 µm. Leg 1: 7.50 (2.10 + 0.30 + 1.95 + 2.40 + 0.75), tibia 2: 1.80, tibia 3: 1.60, tibia 4: 2.10; tibia 1 L/d: 22.

Colour (in ethanol): Prosoma and legs mostly pale ochre-yellow; darker ochre Y-mark behind ocular area; legs without dark rings; abdomen monochromous pale grey.

Body: Habitus as in N. poma (cf. Fig. 1B ). Ocular area barely raised. Carapace with indistinct thoracic groove. Clypeus unmodified. Sternum wider than long (0.54/0.42), with pair of distinct anterior processes near coxae 1. Abdomen globular.

Chelicerae: As in Figure 22G, H ; with large patch of strong hairs on each side; without frontal processes; stridulatory files on low lateral protrusions.

Palps: Similar to N. colina (cf. Fig. 4 ); proximal segments apparently identical to N. colina ; femur length/width 2.08; tibia length/width 1.10; procursus simple, in lateral view slightly directed towards dorsal, similar to N. colina but without subdistal ventral sclerite and slightly wider ( Fig. 22A–C ); genital bulb similar to N. colina but ventral apophysis less strongly curved towards ventral ( Fig. 22D–F ).

Legs: Without spines and curved hairs; apparently few vertical hairs; retrolateral trichobothrium of tibia 1 at 63%; prolateral trichobothrium absent on tibia 1; tarsus 1 with seven to eight pseudosegments, distally distinct.

Variation (male): Tibia 1 in three other males from type locality: 1.71, 1.72, 1.83. The male from 1 km SW Alemanía has apparently identical chelicerae and pedipalps but is smaller: tibia 1: 1.40; carapace width: 0.63; chelicerae maximum width: 240 µm.

Female: In general, similar to male ( Fig. 1E ) but sternum without pair of anterior humps. Tibia 1 in four females: 1.46, 1.47, 1.65, 1.85. Epigynum ( Fig. 23 ) anterior plate roughly rectangular, weakly protruding, with short but wide posterior indentation; posterior plate large, simple. Internal genitalia ( Figs 22I , 23B– D ) simple, with indistinct ‘receptacle’.

Distribution: Known only from two neighbouring localities in Salta, Argentina ( Fig. 3 ).

Natural history: At the type locality, the spiders were found in small cavities or shelters composed of large rocks in a dry ravine. They were sitting relatively exposed on the ceiling of the cavities and were easy to collect as they barely moved. Several females carried egg-sacs that were consistently reddish, flattened, and contained approximately 15– 18 eggs. Near Alemanía, the single pair was found close together on the underside of a large rock. The spiders barely moved at disturbance. They shared the microhabitat with a tiny undescribed species of Modisiminae .

Figures

Figure 1. Nerudia, live specimens from Argentina. A, N. colina sp. nov., female from Jujuy, between San Salvador and Purmamarca (type locality). B, N. poma sp. nov., male from Salta, NW Campo Quijano (type locality). C, D, N. centaura sp. nov., male and female from Catamarca, E Paso de San Francisco (type locality). E, N. trigo sp. nov., female from Salta, SW Alemania. F, N. guirnalda sp. nov., male from Catamarca, El Rodeo (type locality). G, N. ola sp. nov., male from San Juan, San Agustin de Valle Fertil (type locality). H, N. nono sp. nov., male from Cordoba, E Nono (type locality).

Figure 3. Known distribution of Nerudia in South America (inset) and of individual species. Regions in Chile: AT, Atacama; COQ, Coquimbo. Provinces in Argentina: CA, Catamarca; COR, Córdoba; JU, Jujuy; LR, La Rioja; SA, Salta; SJ, San Juan.

Figure 4. Nerudia colina sp. nov.; paratype male from Argentina, Jujuy, between San Salvador and Purmamarca (ZFMK Ar 23883). Left palp, prolateral (A) and retrolateral (B) views. Abbreviations: b, genital bulb; c, coxa; e, embolus; f, femur; p, procursus; pa, patella; ta, tarsus; ti, tibia; tr, trochanter; va, ventral apophysis. Scale line: 0.3 mm.

Figure 22. Nerudia trigo sp. nov.; paratype male and paratype female from Argentina, Salta, between Alemanía and Cafayate (ZFMK Ar 23894). A–C, left male palpal tarsus and procursus, prolateral, dorsal, and retrolateral views. D–F, left male genital bulb, prolateral, dorsal, and retrolateral views. G, H, male chelicerae, frontal and lateral views. I, cleared female genitalia, dorsal view. Scale lines: 0.2 mm.

Figure 23. Nerudia trigo sp. nov.; paratype female from Argentina, Salta, between Alemanía and Cafayate (ZFMK Ar 23894). A, abdomen and epigynum, ventral view. B, median structures in internal genitalia (arrow points at possible pore plate). C, D, cleared genitalia, ventral and dorsal views. Scale lines: 0.2 mm (A, C, D), 0.1 mm (B).

Figure 24. Nerudia trigo sp. nov.; female from Argentina, Salta, between Alemanía and Cafayate (ZFMK Arg206). A, female spinnerets. B, female palpal tarsal organ. C, tarsal organ on female right tarsus 4. D, ‘regular’ hairs on female abdomen. E, hairs on female anal cone. F, left female chelicera, lateral view (note absence of stridulatory file). G, epigynum, ventral view. H, female ALS. Scale lines: 20 µm (A, F), 2 µm (B, C), 10 µm (D, E, H), 100 µm (G).