Figs 1 –3, 6–26, 35
Types: male holotype and female paratype from Sendero Jumandy, Reserva Ecológica Antisana, Napo, Ecuador (0.6245 °S, 77.8402 °W, 2260 m elev.), 29.X. 2010, W. & D. Maddison & M. Reyes (WPM# 10 -035), deposited in QCAZ, temporarily held at the UBC-SEM.
Additional material examined: ECUADOR: Napo: Papallacta (0.370 °S, 78.143 °W, 3300-3400 m elev.): 1 male, 1 female, 25–27.X. 2010, W. Maddison & M. Reyes (WPM# 10 -028). Reserva Ecológica Antisana, Sendero Jumandy (0.6245 °S, 77.8402 °W, 2260 m elev.): 5 males (one of which used in SEM images), 6 females, 4 juveniles, 29.X. 2010, W. & D. Maddison & M. Reyes (UBC-SEM).
Etymology: The species epithet, a noun in apposition, refers to the volcano Antisana, and to the reserve from which the type specimens were collected.
Diagnosis: Males of this species are easily distinguished from both U. edwardsi sp. nov. and U. occidentale sp. nov. by the square ventral lobe of the RTA, with no acute projection (Fig. 23). Females have copulation openings slightly obliquely placed on the epigynal plate (Fig. 25). At least in the northern localities east of Quito, this species is easily distinguished from U. edwardsi by having dark brown rather than yellow legs (Figs 1–5), though leg colour may vary geographically.
Description: Male (holotype): Total length: 2.75. Carapace dark brown, 1.45 long, 1.00 wide, 0.70 high; white diverticuli seen through tegument. Ocular quadrangle 0.75 long. Anterior eye row 0.95 wide and posterior 0.90 wide. Chelicera light brown. Sternum dark brown. Labium and endite yellow. Palp dark brown, tibia with a wide RTA forming a hook dorsally and an acute RvTA; embolus fixed to the tegulum and curling around it, with a median blunt projection lying in a pit of the prolateral side of tegulum (Figs 22–24). Leg I dark brown with yellow tarsus, II–IV light brown, dark brown in femora, along a proventral stripe in patellae and tibiae, and in distal third of metatarsi. Length of femur I: 0.97, II: 0.65, III: 0.60, IV: 0.77; patella + tibia I: 1.30, II: 0.80, III: 0.60, IV: 0.80; metatarsus + tarsus I: 0.90, II: 0.60, III: 0.70, IV: 0.87. Leg spination: femur I 0, II–III d 0-1 - 1, IV d 0-1 - 1 or d 1 - 1 - 1; patella I–IV 0; tibia I p 0-1, v 0-1 r- 2, II v 1 r- 1 r-0, III-IV 0 or r 0-1 -0; metatarsus I–II v 2 - 2, III p 0-1, r0, IV p 0-1, r 0-1, v 1 p-0. Abdomen and spinnerets dark brown.
Female (paratype): Total length: 2.85. Coloration as in male, with lighter carapace and legs. Carapace 1.37 long, 0.95 wide, 0.70 high. Ocular quadrangle 0.72 long. Anterior eye row 0.90 wide and posterior 0.87 wide. Palp with dark brown femur, yellow patella, dark brown tibia and yellow tarsus. Length of femur I: 0.75, II: 0.60, III: 0.50, IV: 1.00; patella + tibia I: 0.87, II: 0.70, III: 0.55, IV: 0.80; metatarsus + tarsus I: 0.65, II: 0.55, III: 0.57, IV: 0.77. Leg spination: femur I–II 0, III–IV d0- 0-1; patella I–IV 0; tibia I v 1 r- 1 r-0, II v 0-1 r-0, III–IV 0; metatarsus I– II v 2 - 2, III p 0-1, r0, IV p 0-1, r 0-1. Epigyne with small U-shaped copulation openings forming an atrium; copulation ducts begin as wide chambers and extend backwards, fold at the center, extend anteriorly and connect to small spermathecae, from which fertilization ducts emerge (Figs 25–26).
Distribution. Known only from Napo, Ecuador (Fig. 35).