(Figs 13 and 15) CORBIDI 04773, adult male from Peru, Region Loreto, Provincia Datem del Marañón, Pampa Hermosa (3.0650°S, 75.8264°W), 200 m above sea level, collected by V. Duran on 28 March 2008.

Five adult males: Ecuador: Provincia de Orellana: Pompeya-Iro road, km 80, Río Beye, QCAZ 51205, collected by E. Toral, I. G. Tapia, T. Camacho, and S. R. Ron on 31 May 2011; Provincia Pastaza: Nuevo Corrientes, 250 m above sea level, QCAZ 14947, collected by F. Villamarín on August 2000. Peru: Provincia Datem del Marañón: Andoas (2.6516°S, 76.5137°W), 151 m above sea level, CORBIDI 01086, collected by A. Delgado on September 2008; Jibarito (2.7356°S, 76.0318°W), 197 m above sea level, CORBIDI 06469, collected by A. Delgado on 14 July; Capihuari Norte (2.6642°S, 76.5012°W), 270 m above sea level, CORBIDI 05031, collected by J. C. Chaparro on March 2008.

Throughout this section, coloration refers to preserved specimens unless otherwise noted. Osteocephalus vilmae is a medium-sized species of Osteocephalus having the following combination of characters in males (females are unknown): (1) maximum SVL in males 55.77 mm (n = 6); (2) skin on dorsum bearing few scattered to abundant tubercles; (3) skin on flanks areolate with big flattened warts; (4) hand webbing formula varying from I basal II basal III2^–—2IV to I basal II1²/₃—2²/₃III2²/₃—2½IV; foot webbing formula varying from I1—1½II1—2^–III1^–—2IV2^–—1^–V to I1⁺—2 II1—2III1⁺—2⁺IV2—1⁺V (Fig. 16); (5) dorsum varying from light brown with dark brown marks to light gray with dark brown marks; (6) venter varying from light gray to tan with lighter dots and/or dark brown blotches; (7) cream suborbital mark present, clear labial stripe absent; (8) flanks cream with darker reticulations and dark marks; (9) dermal roofing bones of the skull weakly exostosed; (10) in life, bones green; (11) in life, iris light cream to dirty cream with irregular reticulations; (12) paired vocal sacs small, located laterally, behind jaw articulation, (13) juveniles unknown; (14) larvae unknown.

Osteocephalus vilmae is most similar to Osteocephalus buckleyi and Osteocephalus cannatellai. Itdiffers from Osteocephalus buckleyi in having (1) scattered and weakly keratinized dorsal tubercles (abundant and keratinized in Osteocephalus buckleyi), (2) larger size (Osteocephalus vilmae mean male SVL = 55.77, SD = 3.17, n = 5; Osteocephalus buckleyi mean male SVL = 41.12, SD = 2.49, n = 24; differences are significant: t = 6.50, P < 0.001; Fig. 5), and (3) more extensive and conspicuous areolate area on flanks (from axillary region to groin, with big flattened warts, in Osteocephalus vilmae; restricted to anterior one half of flank in Osteocephalus buckleyi). The range of genetic distances (uncorrected p for gen 12S) between Osteocephalus vilmae and Osteocephalus buckleyi is 0.9 to 1.6%. Both species are sympatric at km 80 Pompeya-Iro road indicating the existence of reproductive barriers between them.

Osteocephalus vilmae differs from Osteocephalus cannatellai in having a larger tympanum (~1/4 of head length in Osteocephalus vilmae vs. ~1/5 in Osteocephalus cannatellai), and areolate flanks with big flattened warts (areolate with small flattened warts in Osteocephalus cannatellai). Mitochondrial DNA sequences show that Osteocephalus vilmae and Osteocephalus cannatellai are not sister species (Fig. 1). Osteocephalus vilmae differs from Osteocephalus cabrerai in (1) lacking prominent tubercles on the lower jaw, (2) having smooth outer edge of Finger IV (outer edge with fringe in Osteocephalus cabrerai), (3) having less webbing in the hands (in Osteocephalus vilmae webbing reaches two thirds of the distance between the ultimate and penultimate tubercle of Finger IV, in Osteocephalus cabrerai it reaches the proximal border of the ultimate tubercle; Figs 12 and 16), and (4) low to indistinct tubercles in the tarsus (prominent in Osteocephalus cabrerai).

A cream to bronze iris with black reticulations distinguishes Osteocephalus vilmae from Osteocephalus deridens, Osteocephalus oophagus, Osteocephalus planiceps, and Osteocephalus taurinus which have bronze to golden irises with black lines radiating from the pupil; iris coloration also differs from Osteocephalus carri, Osteocephalus festae, Osteocephalus heyeri, Osteocephalus subtilis, and Osteocephalus verruciger which have predominantly dark irises, and from Osteocephalus leoniae which have a bicolor iris (Jungfer 2010; Jungfer and Lehr 2001; Lynch 2002). Osteocephalus vilmae is larger than Osteocephalus exophthalmus (maximum male SVL in Osteocephalus vilmae 55.77 mm, n = 5; in Osteocephalus exophthalmus 32.7 mm, n = 3; Smith and Noonan 2001) and Osteocephalus fuscifacies (maximum SVL = 44.17, n = 21). Skin texture in the flanks distinguishes Osteocephalus vilmae (coarsely areolate) from Osteocephalus mutabor and Osteocephalus yasuni (smooth). Osteocephalus inframaculatus differs from Osteocephalus vilmae in coloration of the ventral surfaces of hindlimbs (bold brown blotches in Osteocephalus inframaculatus are absent in Osteocephalus vilmae; Jungfer 2010).

Adult male, 51.85 mm SVL, head length 18.9, head width 19.0, eye diameter 6.8, tympanum diameter 4.9, femur length 28.0, tibia length 28.7, foot length 22.1. Head narrower than body, nearly as wide as long; snout truncate in lateral and dorsal views; distance from nostril to eye longer than diameter of eye; canthus rostralis distinct and straight; loreal region concave; internarial area depressed; nostrils moderately protuberant, directed laterally; interorbital area flat, lateral margins of frontoparietals distinct through skin; eye large, strongly protuberant; tympanic membrane clearly evident, slightly wider than high, about two thirds of eye length, separated from eye by ca. 85% of its diameter; tympanic annulus distinct except dorsally where it is covered by supratympanic fold; posterior end of supratympanic fold reaches mid arm insertion. Arm slender, axillary membrane present, reaching one third of arm length; three small low tubercles present along ventrolateral edge of forearm; relative length of fingers I<II<IV<III; fingers bearing large, oval discs, that of third finger about three fourths of tympanum diameter; subarticular tubercles prominent, round to ovoid, bifid in distal subarticular tubercle of Finger IV; supernumerary tubercles present; palmar tubercle small, elongated; prepollical tubercle large, flat, elliptical; prepollex enlarged; large dark keratinous nuptial excrescences covering inner surface of prepollex almost reaching the proximal border of disk of thumb; webbing basal between fingers I and II; webbing formula of fingers I basal II1½—2½III2+—2IV. Medium sized to small tubercles on tibiotarsal articulation; scattered low tubercles on tarsus, more abundant on outer edge; small tubercles scattered along ventrolateral edge of foot; toes bearing discs slightly wider than long, smaller than those of fingers; relative length of toes I<II<V<III<IV; outer metatarsal tubercle ill defined, small, round; inner metatarsal tubercle large, ovoid; subarticular tubercles single, round, protuberant; supernumerary tubercles restricted to the soles; webbing formula of toes I1—2^–II1—2III1—2IV2—1^–V. Skin on dorsum, head, and dorsal surfaces of limbs shagreen, with scattered tubercles; minute keratinized conical tubercles present on the eyelids and dorsal surface of head; skin on flanks areolate with big flattened warts; skin on venter coarsely granular; skin on ventral surfaces of head and thighs granular, that on shanks smooth. Cloacal opening directed posteriorly at upper level of thighs; short simple cloacal sheath covering cloacal opening; round tubercles below vent; two distinct white tubercles ventrolateral to vent. Tongue cordiform, widely attached to floor of mouth; dentigerous processes of the vomers angular, adjacent medially, posteromedial to choanae, bearing 9 and 6 (left/right) vomerine teeth; choanae trapezoidal, oblique; vocal slits short and curved posteroventral to the angle of snout at the base of tongue; vocal sac barely distinct above the arm and below the ear.

Color of holotype in preservative. Dorsum brown with a single diffuse interorbital mark; dorsal surfaces of forearms brown with diffuse brown bands; dorsal surfaces of hindlimbs brown with diffuse dark brown marks on shanks and feet. Venter dirty cream with light brown spots, more abundant on posterior half of the body; ventral surfaces of hindlimbs and forelimbs dirty cream without marks but with distinct white tubercles on forearms; outer half of ventral surfaces of forearms dark brown; sides of head light brown with oblique white bar from posteroventral border of orbit to border of jaw, below tympanum; vertical diffuse brown bar below eye, anterior to white bar; area behind white bar and eye dark brown including periphery of tympanum; flanks dirty cream, areolate region with brown reticulation. Iris silver with a brown mid-horizontal line and thin black reticulations.

Color of holotype in life. Based on digital photograph (Fig. 15). Dorsum pale brown without marks; canthal region pale brown with diffuse pale green subocular mark and dark stripe along the posterior half of upper lip; tympanum pink; flanks light green without marks; dorsal surfaces of thighs and tarsus pale brown with greenish brown transversal bands, forearms greenish brown; tibia pale brown without marks; anterior and posterior surfaces of thighs, concealed surfaces of tibia, and metatarsus pale blue. Venter dirty cream with light brown spots, more abundant on posterior half of the body; ventral surfaces of hindlimbs and forelimbs dirty cream. Iris dirty cream with brown transversal midline and black reticulations.

The specific name is a patronym for Vilma Duran, in recognition of her continued work and efforts toward the improvement of the herpetological collection of CORBIDI and also for collecting the holotype and tissue of this new species.

Dorsal and ventral coloration of preserved specimens is shown in Figure 17. Dorsal background coloration varies from light brown to brown; irregular dark brown or dark gray marks are always present (Fig. 17). Flanks are always cream to grayish cream. Two specimens have a cream middorsal line from the tip of the snout to the vent (CORBIDI 06469, QCAZ 51205). The prominence of the tubercles can decrease in preserved specimens: when collected, CORBIDI 01086 had large conspicuous dorsal tubercle, in preservative tubercles are barely noticeable.

Ventral surfaces of preserved specimens (Fig. 17) vary from cream to vanilla. In most specimens, there are dark brown spots, more distinct posteriorly or in the throat (e.g., CORBIDI 06469); ventrally, limbs vary from dirty cream to light brown; all specimens have small white tubercles in the external edge of the forearm. The vent region is gray to brown with dark brown flecks or dots. Flanks are cream to gray, areolate, with dark brown reticulations, dots, and blotches along the entire flank or restricted to the posterior half (e.g. CORBIDI 05031).

Head shape is truncate in dorsal view and truncate in lateral view. Lateral head coloration varies from light brown with dark mottling (CORBIDI 01086) to grayish white with dark brown canthus rostralis and preocular stripes (CORBIDI 05031). All specimens have a white to cream subocular mark. The tympanic annulus is concealed dorsally and has lighter color than the background. The distal subarticular tubercle on Finger IV is bifid in all specimens.

Adult morphometric data are summarized in Table 3.In the examined series, the largest male has a SVL of 55.77 mm; mean male SVL = 50.74 mm (n = 6, SD = 3.17).

Based on a digital photograph of adult male CORBIDI 01086: dorsum light brown with irregular dark brown and light green marks; canthal region greenish brown with white subocular mark and dark brown band along posterior half of upper lip; tympanum pink contrasting with dark brown tympanic annulus; flanks light green with dark brown reticulation anteriorly and few irregular dark brown blotches posteriorly; dorsal surfaces of thighs, shanks and forelimbs brown with dark brown transversal bands; posterior surfaces of thighs light green; venter white speckled with light brown blotches; iris light cream with brown mid-horizontal line and fine black reticulations.

Osteocephalus vilmae is know from seven localities in the Peruvian and Ecuadorian Amazon basin (northern Loreto region), four at Río Corrientes (Jibarito, Nuevo Corrientes, Pampa Hermosa, and Shiviyacu), two near Rio Pastaza in the border Ecuador-Peru (Andoas and Capahuari Norte) and one at Provincia de Orellana, Pompeya-Iro road (Fig. 2). The elevations of these localities are between 150 to 270 m above sea level. Maximum airline distance between localities is 158 km. The Peruvian localities are dominated by Terra Firme forest. Specimens collected in Capahuari Norte were found in a stream surrounded by a mixture of primary and secondary forest. In Jibarito, Pampa Hermosa, and Shiviyacu the frogs were found in primary forest in a swamp close to a stream. All specimens were next to the streams, perching on tree branches 100 to 200 cm above the ground. Osteocephalus vilmae occurssympatrically with Osteocephalus buckleyi at km 80 Pompeya-Iro road. At the Peruvian localities it co-occurs with Osteocephalus mutabor and Osteocephalus planiceps.