Maurymontia argentina ( Canals, 1939 ), 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 : 236-241

Maurymontia argentina ( Canals, 1939) comb. nov.

( Figs 1A–E , 2A , 3–7 )

Ceratomontia argentina Canals 1939: 144 [part], figs 1, 2, 6, 8, 10; Ringuelet 1955a: 13 [part]; Ringuelet 1955b: 283; Ringuelet 1956: 137 [part]; Ringuelet 1957: 23; Ringuelet 1959: 255 [part], fig. 31; Ringuelet 1963: 41; Capocasale 1966: 631; Capocasale 1968: 69; Muñoz-Cuevas & Vachon 1979: 253, figs A–B; Galiano & Maury 1979: 323; Soares & Soares 1979: 173; Maury & Roig Alsina 1985: 84, figs 1–4, 13, 17; Acosta 1993: 16; Capocasale & Gudynas 1993: 8; Acosta & Maury 1998: 579; Maury 1999: 34; Kury 2003: 20; Porto et al. 2022: 685–686, figs 4–5.

Type material. ♂ holotype ( MLP 24085 ) from Argentina, Buenos Aires Province, Olavarría. I-1916, Withe col. (not examined, lost) .

♂ Neotype (MACN-Ar 7904) from Argentina. Buenos Aires, Sierra La China ( 25 km from Olavarría): E. Maury col., 19-III-1983, 1 ♂.

Remark: The holotype specimen could not be located in the arachnological collection of the Museo de La Plata and is therefore herein considered lost. The Ceratomontia argentina female paratype MACN-Ar 4537 (examined) designated by Canals (1939) is a misidentification of Ceratomontia centralis (see Maury & Roig Alsina 1985:84). To provide a stable and objective reference point for the species, we designated the neotype. This is particularly relevant for this species, given its broad geographic distribution and reported occurrences in other countries ( e.g., Uruguay and Brazil), some of which require verification.

Additional material examined. ARGENTINA. Buenos Aires, Sierra La China ( 25 km from Olavarría): E. Maury col., 19-III-1983, 1 ♂ 1 ♀ (MACN-Ar 7904) . Buenos Aires, Sierra la Brava : Galiano col., 11-XI-1962, 1 ♀ (MACN-Ar 7905) . Buenos Aires, Tandil : E. Maury col., XI-1967, 1 ♂ (MACN-Ar 7903) . Same locality: E. Maury col., 11-IV-1968. 2 ♀ (MACN-Ar 46007) . Same locality: A. Porta col., 06-XII-2018, 5 ♂ 3 ♀ (MACN-Ar 46013) . Same locality: F. Silvestri 13-XI-1898, 1 ♂ 1 ♀ (MACN-Ar 46020) . Same locality, III-1950 1 ♂ 1 ♀ (MACNAr 46021) . Buenos Aires, Tandil, Sierra del Tigre : A. Porta col., 27-V-2013, 1 ♂ 2 ♀ (MACN-Ar 46015) . Same locality: A. Porta col., 12-X-2014, 6 ♀ 4 imm (MACN-Ar 46014). Buenos Aires, Sierra de la Ventana: H. Castello col., X-1969, 1 ♂ 3 ♀ 1 imm (MACN-Ar 7899). Same locality: A. Prosen col., X-1945, 3 ♀ (MACN-Ar 7900) . Same locality: C. Scioscia col., X-1988, 1 ♂, 1 ♀ (MACN-Ar 46012) . Same locality: Ramírez col., 6-III-1994, 1 ♀ (MACN-Ar 46009) . Same locality: Peretti col., 19-20-XII-1990, 1 ♀ (MACN-Ar 46010) . Buenos Aires, Sierra de la Ventana, Las Espadañas , cordón Esmeralda: E. Maury, C. Cesari, P. Dominguez col., 3–6-X-1973, 1 ♀ (MACNAr 7901) . Buenos Aires, Sierra de la Ventana (hill behind the provincial hotel): Galiano col., 14-XI-62, 1 ♂ (MACNAr 7906) . Buenos Aires, Sierra de la Ventana, between Pringles and Saavedra : Goloboff col., 26–29-VIII-1987, 1 imm (MACN-Ar 46011) . Buenos Aires, Tornquist, ruta provincial 76, Sierra del Pantanoso : Grismado, Izquierdo, Piacentini, Ojanguren col., 19–21-VI-2009, 1 ♂ 1 ♀ (MACN-Ar 46008) . Buenos Aires, Coronel Suárez, near Cerro Querencia : A. Porta, E. Guerrero col., 24-IX-2016, 2 ♂ 1 ♀ (MACN-Ar 46016) . Buenos Aires, Tornquist, Sierra de La Ventana, Cerro Ceferino , S38.127720, W61.790265, 150 m: división de aracnología col., 8–12-VIII-2022, 2 ♂ (MACN-Ar 46018) . Same data 12 ♂ 8 ♀ (MACN-Ar 46019) . Buenos Aires, Sierra de la Ventana, 09-XI-2001, S 30.09277 W 61.95972, 1 ♂ (MACN-Ar 46021) . Buenos Aires, Saavedra , on the side of the road, Abra El Hinojo, S37.759192, W62.140809, 452 m: división de aracnología col., 8-VIII-2022, 3 ♂ 2 ♀ 1 imm (MACN-Ar 46017). Buenos Aires, Saavedra, Estancia Cerro Áspero , on the hillside “El Vigilante” 33 km SE de Pigüé, S37.789526 W62.135665 ( Maps.Me) elev. 505 m ( Google Earth), mountain pasture, general survey: División aracnología MACN, 8-VIII-2022, 1 ♂ (MACN-Ar 47875) . URUGUAY. Lavalleja, Aguas Blancas , 28-Oct-1956. Leg. F. de H. y Ciencias, 1 ♀ .

Material not examined (unconfirmed records). ARGENTINA, Buenos Aires, Tandil, Cerro Las Ánimas, Cerro Pelado, Abra de la Ventana; 5 km of Bahía Blanca; Sierra de la Ventana. Buenos Aires, Tandil, Olavarría, Reserva Natural del Tigre, S 37.37820 W 59.12390. Buenos Aires, Tornquist, Parque Provincial Ernesto Tornquist, S 38.06731 W 62.02046. ( Guerrero 2019; Ringuelet 1962; Schwerdt et al. 2014). BRAZIL, Rio Grande do Sul, S 30 km NE São Leopoldo ( Maury 1999). URUGUAY, Colonia, Ruta 1, km 125. Lavalleja, Aguas Blancas; Cerro Arequita; Cerro Penitente. Maldonado, Abra Perdomo; Sierra de las Animas. Rocha, San Miguel. San José, Sierra Mahoma (Maury & Roig Alsina 1985; Capocasale 1968; Capocasale & Gudynas 1993).

Comparative diagnosis. This species is readily distinguishable from other members of the genus by the prominently forward projected ocularium in males ( Figs 3 A, C ; 4 A–B ).) The ventral surface of the pedipalp femur exhibits 2–3 basal cruciform tubercles ( Fig. 5 C–D ). Additionally, the capsula interna is wider compared to other species within the genus, and the lamellae of the ventral plate is narrower than in other species of the genus ( Fig. 7 ).

Measurements neotype (MACN-Ar 7904): Total length 2.73; carapace length 0.96, maximum width 1.41; dorsal scutum length 1.94, maximum width 1.70. Pedipalps: trochanter 0.22, femur 1.06, patella 0.52, tibia 0.88, tarsus 0.72. Leg I: trochanter 0.22, femur 0.86, patella 0.40, tibia 0.51, metatarsus 0.64, tarsus 0.50. Leg II: trochanter 0.23, femur 1.15, patella 0.51, tibia 0.93, metatarsus 0.97, tarsus 0.77. Leg III: trochanter 0.19, femur 0.80, patella 0.30, tibia 0.61, metatarsus 0.79, tarsus 0.53. Leg IV: trochanter 0.23, femur 1.12, patella 0.50, tibia 0.92, metatarsus 1.18, tarsus 0.58.

Redescription. Male (MACN-Ar 7904). Dorsum ( Figs 3 A, C ; 4 A–B ). Eta (η) hourglass-shaped dorsal scutum. Ocularium conical, pointed forward, longer than all other species of Maurymontia adorned with granules. Eyes are proximally located in the dorsolateral view of the ocularium. The dorsal scutum reveals well-defined areas covered by small tubercles. Areas I–III possess a pair of small tubercles with setae, while area IV has 5─8 tubercles. The posterior border is adorned with six tubercles, and lateral grooves of the dorsal scutum are bifurcated on each side. Free tergites are covered by tubercles, bearing sparse setae.

Venter ( Figs 3 E , 4 C–D ). Coxa I displays a medial tubercle with subdistal seta and 7–9 small tubercles with setae. Coxa II and IV microgranulate in the distal part, coxa III lacks microgranulation, and coxa IV has small tubercles in the distal part, without a bridge in the coxa IV. Spiracles are visible. The sternum is arrow-shaped.

Chelicerae ( Fig. 5 A–B ). Segment I of the chelicerae has five small tubercles on the ectal surface, 8–9 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, eight in mesal view, and eight in frontal view.

Pedipalp ( Fig. 5 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 dorsal view, a row of three asymmetric ventral tubercles with subdistal (proximal) setae, and two small tubercles with subdistal setae (distal), parallel to a row of small rounded tubercles with setae. Mesal area covered by small rounded tubercles and two 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 (~10).

Legs ( Fig. 6 ). Leg I trochanter with one dorsal tubercle, femur with four dorsal and four long ventral 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. 7 ). Pars distalis with a ventral plate, without a cleft, forming a single lamella, longer than wide, with five macrosetae on each side; capsula externa higher than the ventral plate, surrounding the capsula interna that is tubular in shape. The capsula interna is longer than the capsula externa. Distal portion of the stylus with a dorsal groove.

Female

Measurements female (MACN-Ar 7902): Total length 2.44; carapace length 0.80, maximum width 1.18; dorsal scutum length 1.75; mesotergum maximum width 1.56. Pedipalps: trochanter 0.18, femur 0.71, patella 0.37, tibia 0.60, tarsus 0.62. Leg I: trochanter 0.18, femur 0.70, patella 0.32, tibia 0.48, metatarsus 0.54, tarsus 0.50. Leg II: trochanter 0.20, femur 0.95, patella 0.43, tibia 0.73, metatarsus 0.73, tarsus 0.71. Leg III: trochanter 0.19, femur 0.65, patella 0.28, tibia 0.50, metatarsus 0.59, tarsus 0.48. Leg IV: trochanter 0.21, femur 0.88, patella 0.39, tibia 0.77, metatarsus 0.99, tarsus 0.56.

Variation. ( Fig. 3 B, D, F ). The female is very similar to the male, except for the shorter projection of the ocularium and slightly dilated pedipalp femur.

Distribution. ARGENTINA: Buenos Aires. BRAZIL: Rio Grande do Sul. URUGUAY: Colonia, San José, Lavalleja, Maldonado, Rocha ( Canals 1939; Capocasale 1968; Capocasale & Gudynas 1993; Maury & Alsina 1985; Ringuelet 1959) ( Fig. 2 A ).

Figures

FIGURE 1. Live pictures of Maurymontia argentina comb. nov. (A) male dorsal (resting position), (B) male dorsal (thanatosis position), (C) juvenile dorsal, (D) juvenile ventral. (E) male field picture. Maurymontia mborore sp. nov. (F) lateral view. Figure credits: A—E Abel Pérez-González, F Ivan Magalhaes.

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

FIGURE 3. Maurymontia argentina comb. nov., male (A, C, E), female (B, D, F). Scale bar 1 mm.

FIGURE 4. Maurymontia argentina comb. nov., SEM images of male. Habitus, dorsal (A), lateral (B), ventral (C–D). Scale bars: A–C 500 µm, D 200 µm.

FIGURE 5. Maurymontia argentina comb. nov., SEM images of male. Chelicera, mesal (A), ectal (B). Pedipalp, mesal (C), ectal (D). Scale bars: A–C 200 µm, D 500 µm.

FIGURE 6. Maurymontia argentina comb. nov., SEM images of male. Legs I (A), II (B), III (C), IV (D). Scale bars: A 200 µm, B–D 500 µm.

FIGURE 7. Maurymontia argentina comb. 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.