Chilenuncia rostrata ( Maury, 1990 ) Porto & Derkarabetian & Giribet & Pérez-González, 2024

Porto, Willians, Derkarabetian, Shahan, Giribet, Gonzalo & Pérez-González, Abel, 2024, Systematic revision of the South American “ Nuncia ” (Opiliones, Laniatores, Triaenonychidae), ZooKeys 1207, pp. 1-149 : 1-149

Chilenuncia rostrata ( Maury, 1990) comb. nov.

Figs 50 , 51 , 52 , 53 , 54 , 55

Nuncia rostrata Maury, 1990: 110, figs 25–35; Maury 1992: 4; Kury 2003: 22; Pérez-Schultheiss et al. 2019: 20; Pérez-Schultheiss et al. 2021: 412, fig. 3 a, d.

Material examined.

Holotype. ♂ Chile. Llanquihue, Caleta La Arena, 50 km S de Puerto Montt, Carretera Austral , 07–08. XII. 1985 ( MACN 8703 ) . Paratype (allotype ♀). Chile. Llanquihue, Caleta La Arena, 50 km S de Puerto Montt, Carretera Austral , 07–08. XII. 1985 ( MACN 8704 ) . Paratypes. Chile. Llanquihue, Caleta La Arena, 50 km S de Puerto Montt, Carretera Austral , 07–08. XII. 1985 ( MACN 8705 ) .

Additional material.

Chile. Llanquihue: 35 km W. Río Negro, R. Schuh, N. Platnick coll., 24. I. 1986, 1 ♀ ( AMNH). Chiloé: Chiloé Island, 5 km N of Quellón, R. Schuh, N. Platnick coll., 01. XII. 1981, 1 ♀ 1 imm. ( AMNH), Isla Chiloé, R. Schuh, N. Platnick coll., 29. XI. 1981, 1 ♂ 1 ♀ ( AMNH). Llanquihue: P. N. Alerce Andino, N. Platnick, K. Catley, M. Ramírez, T. Allen coll., 23. XI. 1993, 1 ♀ 2 imm. ( AMNH). Palena: Termas de Pichicolo, 11 km west of Río Negro, Carretera Austral, E. Maury coll., 08. XII. 1985, 1 ♀ ( MACN 8706). Aysén: 30 km NE de Puerto Cisnes, E. Maury coll., 08. XII. 1986, 2 ♀ 3 imm. ( MACN 8707).

Diagnosis.

This species can be readily distinguished from C. chilensis by the prominent interocular apophysis, which is notably longer in C. rostrata . Additionally, C. rostrata possesses seven tarsomeres on leg II (males), whereas C. chilensis has six. These characteristics serve as key distinguishing features between the two species.

Distribution.

Chile: Los Lagos and Aysén Regions (Fig. 4 C ).

Redescription of male

( MACN 8705). Measurements: Total length 2.97. Carapace length 1.07, dorsal scutum length 2.09, carapace max. width 1.49, mesotergum max. width 1.94. Appendage measurements: Pedipalps. Trochanter length 0.25, femora length 0.95, patella length 0.55, tibia length 0.68, tarsus length 0.66. Leg I: trochanter (tr) 0.25, femora (fe) 0.87, patella (pa) 0.50, tibia (ti) 0.70, metatarsus (mt) 0.89, tarsus (ta) 0.85. II: tr 0.33, fe 1.28, pa 0.54, ti 0.96, mt 1.08, ta 1.45. III: tr 0.32, fe 0.81, pa 0.43, ti 0.66, mt 0.77, ta 0.85. IV: tr 0.34, fe 1.15, pa 0.61, ti 0.95, mt 1.31, ta 1.03.

Dorsum (Fig. 50 , 51 ). Eta (η) hourglass-shaped dorsal scutum. Ocularium elevated, with a long, backward-curving apophysis. Eyes located laterally in the middle of the ocular structure. Dorsal scutum microgranulate and without clear delimitation of areas. Area I with a pair of setae, while areas II – IV display an arcuate row of small setae tubercles. Posterior margin characterized by a row of small setiferous tubercles. All free tergites with a row of small setiferous tubercles.

Chelicerae (Fig. 52 A, B ). Segment I with a small tubercle on its dorso-distal surface; segment II with a mesal tubercle and bears a few setae.

Pedipalps (Fig. 52 C, D ). Trochanter with a small dorsal and ectal tubercle. Femora with two ventroproximal and one ventromedial spine with subdistal setae, with two distal setiferous granules and three dorsoproximal tubercles with subdistal setae. Mesal surface of femora with 2–3 distal setiferous granules. Patella with a ventral setiferous tubercle. Tibia with four ectal and three mesal spines with subdistal setae, while the ventral surface presents small setiferous granules. Tarsus with three mesal and four ectal spines with subdistal setae, as well as a few setae and granules.

Legs (Fig. 53 ). Coxa I with a row of setiferous tubercles, with two distal setiferous tubercles with subdistal setae. Coxae II – III also with setiferous tubercles, while Coxa IV with only microgranulation. Four bridges between legs II and III, and five or six bridges between legs III and IV. Spiracles not obstructed by bridges. A smooth surface covers ~ 1 / 3 of leg II, ¾ of leg III, and <1 / 3 of leg IV. Within the smooth area of leg II, two small tubercles with subdistal setae can be observed on each side. Sternum arrow-shaped, with a triangular posterior area. Smooth, covered in setae, without a notch on tarsus I. Tarsal count 4–7 – 4 – 4.

Penis (Figs 54 , 55 ). Pars distalis with large ventral cleft that divides the plate into two lamellae. Each lamella with three pointed macrosetae on the ventral surface and one macroseta on the dorsal surface. Capsula externa covers dorsal and lateral surfaces, exhibiting a small medial notch that divides the apical region of the capsula externa. With a dorsolateral plate attached to the pars basalis. Capsula interna slightly longer than capsula externa and partially covers the ventral plate. Capsula interna sac-shaped in appearance.

Female. Similar to male, with shorter pedipalpal femora and interocular apophysis.

Female measurements. Total length 3.17. Carapace length 0.98, dorsal scutum length 2.12, carapace max. width 1.38, mesotergum max. width 2.08. Appendage measurements: Pedipalps. Trochanter length 0.21, femora length 0.83, patella length 0.45, tibia length 0.59, tarsus length 0.62. Leg I: trochanter (tr) 0.23, femora (fe) 0.84, patella (pa) 0.52, tibia (ti) 0.69, metatarsus (mt) 0.82, tarsus (ta) 0.64. II: tr 0.30, fe 1.13, pa 0.52, ti 0.89, mt 0.92, ta 1.23. III: tr 0.30, fe 0.73, pa 0.40, ti 0.72, mt 0.79, ta 0.73. IV: tr 0.30, fe 1.13, pa 0.60, ti 0.90, mt 1.27, ta 0.93. Tarsal count: 3–6 – 4 – 4.

Figures

Figure 4. Maps showing the distribution of the species used in this work. South America (Chile and western Argentina inset). Chile in green, Argentina / South America in grey. Terrestrial ecoregions (following Olson et al. 2001) highlighted in yellow (Chilean Matorral) and orange (Valdivian temperate forests).

Figure 50. Chilenuncia rostrata comb. nov. habitus, male A dorsal view C lateral view E ventral view. Female B dorsal view D lateral view F ventral view. Scale bars: 1 mm.

Figure 51. Chilenuncia rostrata comb. nov. male, SEM images of habitus A dorsal view B lateral view C, D ventral view. Scale bars: 500 µm (A, B, C); 200 µm (D).

Figure 52. Chilenuncia rostrata comb. nov. chelicerae: mesal A ectal B Pedipalps: mesal C ectal D. Scale bars: 200 µm (A, B); 500 µm (C, D).

Figure 53. Chilenuncia rostrata comb. nov. legs I A II B III C IV D. Scale bars: 500 µm (A, B, D); 200 µm (C).

Figure 54. Chilenuncia rostrata comb. nov. penis: ventral A, B apical C lateral D, E dorsal F, G. Scale bars: 200 µm (A, D, F); 100 µm (B, E, G); 50 µm (C).

Figure 55. Chilenuncia rostrata comb. nov. penis: ventral A apical B lateral C dorsal D. Colors: ventral plate (yellow), capsula externa (blue), capsula interna (red). Scale bars: 100 µm (A, C, D); 50 µm (B).