Proceratophrys avelinoi Mercadal de Barrio & Barrio 1993

Diagnosis Is a small-sized member of the bigibbosa group (snout-vent length 23.9-29.2 mm in males, 30.2-36.5 mm in females). It is characterized by its small postocular swelling, light brown coloration on the suprascapular region, and orange reddish blotches on the venter.

Known from a few localities in the province of Misiones, Argentina, east of Paraná and santa Catarina states in Brazil, and Itapúa department in Paraguay.

Herbácea

Saponósidos, esteróis(1)

Adult morphologyThe following description is based on 33 specimens. Unless otherwise stated, all ratios are from a total of 33 specimens (with mean ± SD in parentheses). Body small, robust, and stout. Head slightly wider than long; head width 0.42-0.51 times snout-vent length (0.47 ± 0.22); head length 0.34-0.44 times snout-vent length (0.40 ± 0.02). Snout protruding; obtuse and slightly truncate in profile, rounded or negligibly pointed in dorsal view. Canthus rostralis prominent, arising behind each nostril and extending to the beginning of the eyelids. Postocular swelling small, arc-shaped. Small tubercular ridge behind each eye, limiting the tympanum dorsally. Tympanic membrane indistinct, covered with minute homogeneous tubercles. Nostrils ovoid, dorsolaterally positioned. Internarial distance smaller or equal to eye-nostril distance, and 0.14-0.18 times head width (0.16 ± 0.01). Eyelid ornamented with a variable number of enlarged tubercles, covering eyes in dorsal view; most tubercles ovoid, except one larger located in the center of the margin of the eyelid which is nearly triangular. Eye diameter 0.17-0.24 times head length (0.20 ± 0.01; n = 31); interocular space flat or slightly concave. Suprascapular region barely depressed. Tongue cordiform or slightly ovoid. Vomerine teeth in two short, well-separated, transverse rows located behind the choanae. Vocal sac single, subgular. Body, arms, and limbs covered with numerous tubercles and granules of variable size and shape. All tubercles covered with tiny keratinous spines, except those on pubic skin, nasal rim, palm, sole, and tips of fingers and toes. Two longitudinal rows of tubercles, extending from the posterior region of the upper eyelid above dorsum to vent, forming two curved ridges. Ridges narrow until midbody, widen on sacrum, forming a lozenge, and converging on urostyle. Irregular row of 4-7 enlarged tubercles on ventrolateral surface of forearm. Foot length 0.35-0.42 times snout-vent length (0.38 ±0.02) and 1.08-1.25 tibia length (1.14 ± 0.03). Relative length of fingers 4 , 2, 1, 3. Inner and outer metacarpal tubercles subovoid; inner tubercle larger than or equally sized to outer tubercle; inner tubercle usually more prominent. Subarticular tubercles roughly quadrangular and prominent. Rounded supernumerary tubercles of varying number and size, scattered over palmar surface and between subarticular tubercles. Supernumerary tubercle laterodistally to the outer metacarpal tubercle sometimes sligthly enlarged giving the impression of a second, more internally situated, outer metacarpal tubercle. Fingers without webbing, laterally fringed with granulous dermal ridges. Nuptial asperities absent. Webbing between toes with granular texture. Granular dermal fringe reaching the tips of toes. Tips of toes rounded, with granules and keratinized spines on dorsal surface, ventrally smooth. Relative length of toes 1, 2, 5, 3, 4. Outer metatarsal tubercle rounded and small. Inner metatarsal tubercle elliptical and protuberant; its length 0.12-0.16 times foot length (0.15 ± 0.01). Subarticular and supernumerary tubercles of similar size and shape as described for the hand, although present in greater quantity. Tarsal fold absent. Distinct row of two to four tubercles extending from inner metatarsal tubercle to the midpoint of the tarsus. Color in life: When collected, most specimens had a dirty, muddy dorsum, making the dorsal pattern almost invisible. When washed, the predominant dorsal coloration varied from dark reddish brown to light gray. Upper lip with thin light orange line tends to darken in preservative. Three dark brown bands, possessing irregular margins, arising below eye, two of which reach the lip and one reaching beyond the mandible. Another band runs from nostril to lip. Interocular region with dark brown, irregular formed, quadrangular blotch anteriorly and lighter brown triangular blotch posteriorly, its vertex pointing posteriorly. A dark brown, approximately Y-shaped blotch on posterior region of head the arms of which arise at the postocular swellings and extend to the interscapular space. Dermal depression on suprascapular region light brown or tan. Several diffuse bands and blotches distributed over the whole dorsum. Large, dark brown, subtriangular blotches behind each eye, below suprascapular depression and before sacral region. Arms and hind limbs with dark brown stripes. Ventral surface of body and limbs black or dark gray. Venter, palms, and soles of foot with irregular reddish orange or dark red blotches, on venter partly arranged as vermiculations. Red minute spots scattered over gular region. Dorsal half of iris gold, ventral half brown. Variation Morphological variation small, except for development of postocular swelling and ventral color pattern. Females are larger than males. In comparison with other localities, snout profile was slightly more truncate in specimens from Campo San Juan and Aguaray-Guazu. Ventral pattern in specimens from San Vicente usually consisted of several small spots sometimes forming vermiculations posteriorly, and a large, irregular, arc-shaped blotch with the convex side oriented toward the cloaca. Specimens from other populations possessed blotches of irregular size and shape, tending to concentrate laterally on the posterior half of the venter. Larval morphology Proceratophrys avelinoi tadpoles have an elliptical, slightly depressed, and elongated body. In dorsal and lateral views, the snout is rounded; in lateral view, the snout slopes gradually anteriorly toward the oral disc. The eyes are large and directed laterally; eyes are positioned dorsolaterally on the body. The external nares are located half way between the eyes and the tip of the snout. Narial openings are small, rounded, laterodorsally positioned and have a well-defined marginal rim. A low papilla, with a dark pigment spot on its tip, is present on the inner (= medial) margin of the each nare. Tail fins are low, dorsal and ventral fins nearly parallel the tail musculature. Dorsal fin is slightly higher than ventral fin. The dorsal fin originates at the tail-body junction, and the ventral fin originates at the posterior ventral terminus of the body. Tail fins slope to a broadly rounded tail tip. Tail musculature extends to the posterior tip of the tail. The spiracle is sinistral and has a midlateral opening. The vent tube is large; vent tube and vent tube�s apertures are dextrally placed relatively to the ventral fin. Measurements in millimeters (mean ± SD n = 4): body length 12.2 ± 0.62, tail muscle height 3.1 ± 0.3; fin height 5.8 ± 0.54: total length 32.6 ± 3.2; eye diameter 1.1 ± 0.05; interorbital distance 2.6 ± 0.35; body maximum width 7.9 ± 0.64; body width at eyes 6.1 ± 0.37; body width at nostrils 4.2 ± 0.06; body maximum height 6.5 ± 0.72; rostrospiracular distance 6.6 ± 0.34; frontonasal distance 2.2 ± 0.24; naso-ocular distance 1.1 ± 0.21; nostril diameter: 0.38 ± 0.05; eye diameter 1.1 ± 0.05; internarial distance 1.6 ± 0.13; width of oral disc 2.2 ± 0.17; width of dorsolabial gap: 1.4 ± 0.12. Coloration: fixed specimens in 10% formalin are overall brown, with tail musculature being light yellowish. The myotomes of the caudal musculature are visible, but they are not strongly marked. The tail fins and tail musculature are speckled with dark melanophores. Large, irregular-shaped, dark brown spots are scattered over the tail musculature, particularly close to the dorsal edge of the epaxial musculature. Melanophores are more abundant on the dorsal fin than on the ventral fin. The dorsal and dorsolateral surfaces of the body are homogeneously brown, grading continuously to a light brown and almost translucent ventral surface.

Coreia

LC. Least Concern.

Proceratophrys avelinoi is a species of frog in the family Odontophrynidae. It is found in Argentina, Brazil, and possibly Paraguay. Its natural habitats are subtropical or tropical moist lowland forest, rivers, intermittent rivers, pastureland, and heavily degraded former forest. It is threatened by habitat loss.