Maurymontia trescerros, Porto & Iglesias & Pérez-González, 2025

Porto, Willians, Iglesias, Patricia P. & Pérez-González, Abel, 2025, Disentangling the South American “ Ceratomontia ”: new genus, new combinations, and new species (Opiliones: Laniatores: Triaenonychidae), Zootaxa 5729 (2), pp. 233-263 : 257-261

Maurymontia trescerros sp. nov.

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( Figs 2A , 24–28 )

Type material. ♂ holotype (MACN-Ar 46024) from Argentina, Corrientes Province, Departamento Curuzú Cuatiá, Tres Cerros, Cerro Nazareno , Estancia La Higuera Cue , 28 km SE from La Cruz , -29.107907, -56.933217. 20–22- II-2015, M. Ramírez, L. Piacentini det. 1 ♂ 1 ♀ (MACN-Ar 47793), same data .

Etymology. The specific epithet trescerros refers to “Tres Cerros”, the type locality. The noun in apposition maintains the original orthography of this geographically significant site.

Diagnosis. This species can be easily distinguished from the other species of the genus by having more robust tubercles on the free tergites and a ventral plate of the penis with an arched shape and a central portion that is more elevated (slightly triangular), the long dual-lobed end of the capsula externa, and single shorter projection on the dorsal side.

Measurements holotype (MACN-Ar 46024): Total length 2.11; carapace length 0.81, maximum width 1.25; dorsal scutum length 1.70; mesotergal scute maximum width 1.46. Pedipalps: trochanter 0.13, femur 0.79, patella 0.47, tibia 0.75, tarsus 0.70. Leg I: trochanter 0.18, femur 0.76, patella 0.35, tibia 0.50, metatarsus 0.55, tarsus 0.52. Leg II: trochanter 0.17, femur 1.02, patella 0.43, tibia 0.78, metatarsus 0.78, tarsus 0.71. Leg III: trochanter 0.20, femur 0.54, patella 0.31, tibia 0.52, metatarsus 0.62, tarsus 0.40. Leg IV: trochanter 0.21, femur 0.90, patella 0.38, tibia 0.77, metatarsus 0.96, tarsus 0.48.

Description. Male (MACN-Ar 46024). Dorsum ( Figs 24 A–C , 25 A–B ). Eta (η) hourglass-shaped dorsal scutum. Ocularium conical, prominently projected forward, with the dorsal surface adorned with granules. Eyes are proximally located in the dorsolateral view of the ocularium. The anterior margin has 4–5 tubercles each side. The dorsal scutum reveals well-defined areas covered by small tubercles. Areas I–III possess 2–3 small tubercles with setae, while area IV has 4─6 tubercles. Free tergites are covered by robust tubercles, some bearing setae.

Venter ( Figs 24 D , 25 C–D ). Coxa I displays a medial tubercle with subdistal seta and 6–8 small tubercles with setae. Coxa II microgranulate in the distal part, coxa III lacks microgranulation, and coxa IV distal microgranulate, bearing distal tubercles. Spiracles are visible. The sternum is arrow-shaped.

Chelicerae ( Fig. 26 A–B ). Segment I of the chelicerae has four small tubercles on the ectal surface, seven small tubercles on the meso-ventral surface, and a small acute tubercle on the dorso-distal surface. Segment II exhibits ~six small tubercles in ectal view, 8–9 in mesal view, and nine in frontal view.

Pedipalp ( Fig. 26 C–D ). Trochanter with two dorsal tubercles and one ventral tubercle with subdistal setae, ventral surface microgranulate that extend to the femur. Femur with a ventro-ectal tubercle and a row of small tubercles with setae in dorso-ectal view. There is a row of conical tubercles interspersed with small tubercles in the dorsal view. Mesal area covered by small rounded tubercles and three distal conical tubercles with subdistal setae. Patella has an ectal and mesal tubercle with subdistal setae. Tibia is covered ventrally by small rounded tubercles and has three ventral tubercles with subdistal setae on each side. Tarsus has three ventral tubercles with subdistal setae on each side and small scattered ventral tubercles with subdistal setae (~8).

Legs ( Fig. 27 ). Leg I trochanter with two dorsal tubercles, femur with a row of dorsal and ventral long tubercles, smooth patella, tibia with a ventral row of tubercles, metatarsus and tarsus smooth, II–IV with small setiferous tubercles on the femur, astragalus larger than the calcaneus on all legs, tarsal count: 2-3-3-3.

Penis ( Fig. 28 ). Pars distalis with a ventral plate, without a cleft, forming a lamella with triangular shape, longer than wide, with three ventral and two dorsal macrosetae each side; dual-lobed capsula externa higher than the ventral plate, with a single shorter projection on the dorsal side, surrounding the stylus; capsula interna tubular in shape, longer than the capsula externa.

Female

Measurements female (MACN-Ar 47793): Total length 2.67; carapace length 0.80, maximum width 1.25; dorsal scutum length 1.65; mesotergum maximum width 1.74. Pedipalps: trochanter 0.13, femur 0.78, patella 0.45, tibia 0.56, tarsus 0.53. Leg I: trochanter 0.19, femur 0.83, patella 0.35, tibia 0.66, metatarsus 0.80, tarsus 0.48. Leg II: trochanter 0.27, femur 1.26, patella 0.43, tibia 1.03, metatarsus 1.45, tarsus 0.86. Leg III: trochanter 0.23, femur 0.96, patella 0.38, tibia 0.82, metatarsus 1.15, tarsus 0.52. Leg IV: trochanter 0.24, femur 1.29, patella 0.42, tibia 1.04, metatarsus 1.56, tarsus 0.64.

Variation. The female is very similar to the male, except for the shorter ocularium and slightly dilated pedipalp femur.

Distribution. Known only from the type locality ( Fig. 2 A ).

Figures

FIGURE 2. Distribution of Maurymontia species with elevation layers (A). Distribution of Maurymontia species, showing the representation of the Peripampasic Arc (B).

FIGURE 24. Maurymontia trescerros sp. nov., male. Scale bars: A, C–D 1 mm, B 500 µm.

FIGURE 25. Maurymontia trescerros sp. nov., SEM images of male. Habitus, dorsal (A), lateral (B), ventral (C–D). Scale bars: A–C 500µm, D 200 µm.

FIGURE 26. Maurymontia trescerros sp. nov., SEM images of male. Chelicera, mesal (A), ectal (B). Pedipalp, mesal (C), ectal (D). Scale bars: A–B 200 µm, C–D 500 µm.

FIGURE 27. Maurymontia trescerros sp. nov., SEM images of male. Legs I (A), II (B), III (C), VI (D). Scale bars: A, B, D 500 µm, C 200 µm.

FIGURE 28. Maurymontia trescerros sp. nov., SEM images of male. Penis, ventral view (A), ventro-apical view (B), lateral view (C), dorsal view (D–E). Colors: blue (capsula externa), red (capsula interna), green (ventral plate). Scale bars: A–D 50 µm, E 200 µm. Broken stylus represented by a dashed line.