Acanthogonatus monicae Signorotto & Ferretti, 2026, sp. nov.

Acanthogonatus monicae sp. nov. Figs 6, 7, 8, 9, 10 Type material. Holotype. Argentina • 1 ♂; Córdoba, Alpa Corral; 32.68949°S, 64.73351°W; Feb. 2017; N. Ferretti leg.; M 1496. Paratype. Argentina • 1 ♀; Córdoba, Ascochinga; 30.94220°S, 64.27610°W; Feb. 2017; N. Ferretti leg.; M 1498. Additional material examined. Argentina • 1 ♀; Córdoba, Santa Rosa de Calamuchita; 32.07720°S, 64.53980°W; Feb. 2017; N. Ferretti leg.; M 1507 • 1 ♀; Córdoba, Camino del Cuadrado; 31.12861°S, 64.40299°W; Feb. 2017; N. Ferretti leg.; M 1508 • 1 ♀; Córdoba, El Cóndor; 31.63783°S, 64.67997°W; Feb. 2017; N. Ferretti leg.; M 1503 • 1 ♀; Córdoba, La Cumbrecita; 31.90932°S, 64.76510°W; Feb. 2017; N. Ferretti leg.; M 1506 • 1 ♀; Córdoba, Observatorio; 31.58650°S, 64.51630°W; Feb. 2017; N. Ferretti leg.; M 1501 • 1 ♂; Córdoba, El Cóndor; 31.63783°S, 64.67997°W; Oct. 2013; N. Ferretti & M. S. Copperi leg.; M 0427 • 1 ♂; Córdoba, El Cóndor; 31.63783°S, 64.67997°W; Feb. 2017; N. Ferretti leg.; M 1495. Etymology. The specific name monicae is a genitive matronym honoring Mónica, the mother of the first author, in recognition of her constant support and vital role throughout the author’s academic journey. Diagnosis. Males can be distinguished from those of most congeners by the pyriform palpal bulb with a globose tegulum and a long, slender embolus curved prolaterally (Fig. 8 A – D) bearing 8 to 10 subapical prolateral teeth (Fig. 8 G). They resemble males of A. centralis, but differ by the higher number of teeth and a more curved and tapered embolus in dorsal view (Fig. 8 C). Females resemble those of A. centralis and A. parana, but differ from those of A. centralis by the spermathecae with an elongated spermathecal duct leading to a sub-spherical receptacle, with a digitiform internal projection longer or almost the same length of the receptacle (Fig. 9 F) and from A. parana by the narrow fundus of the spermathecae. Description of holotype male (M 1496). Coloration of cephalothorax, legs, and palpi yellowish brown; abdomen of similar coloration, densely mottled with darker brown markings dorsally and paler ventrally, with some dark spots anterior to the spinnerets. Carapace length 5.17, width 3.91 (Fig. 6 A). Abdomen length 5.02, width 1.73. Ocular group length 0.64, width 0.85 (Fig. 6 D). Eye sizes and interdistances: AME 0.19, ALE 0.28, PME 0.17, PLE 0.17; AME – AME 0.14, AME – ALE 0.06, PME – PME 0.34, PME – PLE 0.05, ALE – PLE 0.10, AME – PME 0.07. Anterior eye row slightly procurved, posterior row recurved. Clypeus width 0.1. Fovea straight, 0.62 wide. Chelicerae with 8 prolateral denticles and intercheliceral tumescence bearing 7 long, thin setae. Rastellum weak, formed by basally thick setae tapering apically. Labium length 0.78, width 0.79, without cuspules. Maxillae length 1.49, width 0.83, with 18 cuspules on the left and 23 on the right (Fig. 6 C). Sternum length 2.89, width 1.93, with three pairs of oval marginal sigilla: pair I diameter 0.05, distance to margin 0.05; pair II diameter 0.05, distance 0.02; pair III diameter 0.10, distance 0.04 (Fig. 6 B). Spinnerets: PMS length 0.41; PLS: basal segment 0.80, median 0.43, apical 0.70. Scopula: leg I, tarsus entire, metatarsus 1 / 2; leg II, tarsus entire; leg IV, tarsus entire. All tarsi flexible. Tarsal claws with a double row of 9–10 teeth. Leg and palp measurements are shown in Table 3. Tibia I with a well-developed apophysis bearing two short and stout spines (Fig. 7 A – C). Spination: palp: femur r 1-0 - 0, patella 0, tibia r 1-1 - 0; leg I: femur r 1-0 - 0, d 2-0 - 0, patella r 1-0 - 0, tibia r 3-1 - 1, v 1-2 - 2, metatarsus v 0-1 - 0; leg II: femur 0, patella 0, tibia r 2-4 - 3, v 0-1 - 0, metatarsus r 2-0 - 0, v 1-0 - 0; leg IV: femur d 1-0 - 1, patella r 0-1 - 1, p 0-1 - 0, tibia r 0-2 - 0, p 2-2 - 0, v 2-1 - 2, d 1-0 - 1, metatarsus r 2-0 - 1, p 2-2 - 1, v 3-3 - 2, d 2-3 - 2. Copulatory organ: bulb pyriform with globose tegulum and long, very thin embolus, straight in dorsal view (Fig. 8 A – F), bearing 8–10 subapical teeth (Fig. 8 G). Description of paratype female (M 1498). Color as in male. Carapace length 4.9, width 3.6 (Fig. 9 A). Abdomen length 7.8, width 4.9 (Fig. 9 C, D). Ocular group length 1.3, width 1.8 (Fig. 9 G). Eye sizes and interdistances: AME 0.4, ALE 0.5, PME 0.3, PLE 0.4; AME – AME 0.3, AME – ALE 0.2, PME – PME 0.1, PME – PLE 0.8, ALE – PLE 0.1, AME – PME 0.1. Anterior eye row procurved, posterior row slightly recurved. Clypeus width 0.1. Fovea straight, 0.4 wide. Chelicerae with 7 prolateral denticles. Rastellum weak, formed by basally wide setae tapering apically. Labium length 0.53, width 0.36, without cuspules. Maxillae length 1.9, width 1.14, with 22 cuspules on the left and 24 on the right (Fig. 9 E). Sternum length 3.9, width 4.0, with three pairs of marginal oval sigilla: pair I diameter 0.1, distance to margin 0.025; pair II diameter 0.2, distance 0.077; pair III diameter 0.2, distance 0.138 (Fig. 9 B). Spinnerets: PMS length 0.9; PLS: basal segment 1.5, median 0.8, apical 0.9. Scopula: leg I, tarsus and metatarsus fully scopulated, entire; leg III and IV, tarsus fully scopulated, entire. Non-flexible tarsi. Legs and palp measurements are shown in Table 4. Tarsal claws with a double row of 7 teeth. Spination: palp: femur 0, patella 0, tibia r 1-0 - 0, v 2-0 - 0; leg I: femur d 2-0 - 0, patella 0, tibia r 2-0 - 0, metatarsus v 0-0 - 1; leg III: femur d 2-0 - 1, patella r 0-1 - 0, p 1-1 - 1, d 0-1 - 0, tibia r 1-1 - 0, p 2-1 - 2, v 2-1 - 1, d 0-2 - 1, metatarsus r 2-2 - 2, p 2-4 - 3, v 2-2 - 2, d 2-4 - 3; leg IV: femur d 1-0 - 2, patella r 0-1 - 0, p 0-2 - 0, tibia r 2-2 - 1, p 2-1 - 2, v 3-2 - 2, d 2-1 - 0, metatarsus r 2-2 - 4, p 3-4 - 3, v 3-2 - 3, d 2-2 - 4. Spermathecae with elongate, sub-spherical receptacle with long duct, bearing an internal projection arising from the base of the duct, longer or almost the length of the receptacle (Fig. 9 F). Distribution. Restricted to the Pampean ranges of central Argentina, along the north-central region of Córdoba Province (Fig. 10).