Phyllomedusa boliviana Boulenger 1902

The red-rimmed leaf frog, Phyllomedusa boliviana, is a large green hylid treefrog inhabiting tropical dry forests and rainforest edges in an altitudinal range of 200-1800 m asl. in the Amazonian slopes of the Bolivian Andes, northern Argentina, southwestern Brazil and probably Paraguay (Brusquetti and Lavilla 2006).Faivovich et al. 2005 and Barrio-Amorós (2006) place it in the P. tarsius group (as cited in Frost 2015).Research is needed to determine whether this name includes multiple species.While its population appears stable and it is reported as common throughout its range, its habitats are vulnerable to degradation as a result of encroaching agriculture and wood-gathering (De la Riva et al. 2010). This degradation is especially a threat to arboreal breeding sites and water sources for larval development.Argentinian populations are particularly vulnerable to considerable habitat loss there (Vaira 2001).

Nocturnal and terrestrial, adults males are territorial and use visual leg-stretching signals along with call alerts as aggressive warnings before engaging in male-to-male combat (Jansen and Köhler 2008) for breeding sites. Males call for females from tree perches 35-200 cm from the ground, individually or in small choruses.Mating occurs on leaves on the outer leaves of shrubs hanging over water (Vaila reports that amplectant pairs regularly fall into water and need to return to an oviposition spot to resume mating).Females lay clutches of about 200 eggs onto leaves they fold into “nests” glued together with a mass of eggless capsules.These capsules contain water that keeps eggs hydrated until hatching, when tadpoles drop into the water below (Vaira 2001; Jansen and Köhler 2008; De la Riva et al. 2010).

Artificial breeding ponds such as those developed in Parque Nacional Calilegua, Argentina, that allow for oviposition habitats may be a valuable tool for conservation of P. boliviana and other leaf-breeding species that require specific combination of water sources near appropriate foliage (Vaila 2001).

Vaira, M. 2001. Breeding biology of the leaf frog, Phyllomedusa boliviana (Anura, Hylidae). Amphibia-Reptilia: 421-429.

Jansen, M. and Köhler, J. 2008. Intraspecific combat behavior of Phyllomedusa boliviana (Anura: Hylidae) and the possible origin of visual signaling in nocturnal treefrogs. Herpetological Review 39(3): 290-293.

Diagnosis A large species of Phyllomedusa having 1) the first toe longer than, and opposable to, the second; 2) distinct, well-developed parotoid glands; 3) prevomerine teeth present in adults; 4) no calcar or dermal appendages; 5) a lightly reticulated palpebral membrane; 6) iris black-brown in life; 7) in life, upper eyelid edged with red, tubercles on flank white, tipped with red; concealed surfaces of hindlimb pale yellow-green with no markings.

Known from the Andean slopes and eastern lowlands of Bolivia, and the lowlands of western Brazil (Matto Grosso and Rondonia states) and northern Argentina, at elevations of 350-2000 m.

Redescription of male syntype Head wider than body; snout short, rounded in dorsal view; in lateral view, truncate and inclined posteriorly from lip to nostril; canthus rostralis rounded, distinct; loreal region barely concave; lips thin and not flared; nostrils not protuberant, directed laterally; internarial region flat; eyes not protuberant; pupil vertically elliptical; palpebrum finely reticulated; parotoid gland well-developed, extending from eyelid to a point level with the insertion of the arm; supratympanic fold moderately developed, barely obscuring upper edge of tympanum; tympanum distinct, oval; anterior edge of tympanum separated from posterior corner of eye by distance of 1 mm. Axillary membrane absent; upper arm slender, forearm robust; ulnar fold low; relative lengths of fingers 1-2-4-3 from shortest to longest; finger discs about three-fifths diameter of tympanum; subarticular tubercles large, round to conical; supernumerary tubercles lacking on fingers; palmar tubercle barely distinct; prepollex enlarged, elliptical, bearing thin, horny nuptial excrescence; fingers lacking webbing. Leg of moderate length, slender; no calcar or dermal ornamentation; inner tarsal fold absent; outer tarsal fold barely distinct; relative lengths of toes 2-1-3-5-4 from shortest to longest; toe discs rounded, shorter than those on fingers; inner metatarsal tubercle elliptical, low, flattened; outer metatarsal tubercle absent; no webbing between toes; subarticular tubercles large, round to conical; no supernumerary tubercles on toes. Anal opening directed posteriorly at midlevel of thighs; anal opening a short tube, no flap; supra-anal fold present; pair of large tubercles present inferior and lateral to anus; skin of dorsal surfaces smooth, no tubercles; skin of chin and pectoral region finely areolate; skin of belly and ventral surface of thigh tubercular; skin of remaining ventral surfaces of limbs smooth, except for that of forearm and tarsus, which bears a few discrete tubercles; anterior flank tuberculate, posterior flank smooth; tongue lanceolate, barely notched posteriorly; free for about one-half its length; prevomerine teeth present; dentigerous processes of prevomer small, separated medially by distance equal to width of one process, processes directed posteromedially at midlevel of elliptical choana; vocal slit short, extending from posterolateral corner of tongue to corner of mouth; vocal sac single, median, subgular. Color in preservative: dorsal surfaces pale blue; dorsal surfaces of finger and toe discs gray; ventral surface of chin pale brown, with few diffuse cream spots; ventral surface of belly and thigh cream; ventral aspects of forearm and tarsus pale brown, with discrete white tubercles; ventral surfaces of hand and foot pale brown; ventral surfaces of shank and inner aspect of tarsus pale gray with pale brown mottling; anterior and posterior aspect of thigh pale blue-violet; few, indistinct white tubercles present on posterior aspect of thigh; anal region pale brown; paired anal tubercles and supra-anal fold white; white stripe present along heel, tarsus, and lateral border of fifth toe; border of upper eyelid, lower lip, and anterior flank white; most tubercles of anterior flank capped with small spot of dark gray pigment; white stripe at point of insertion of arm, demarcating the blue color of upper arm from cream region of chest; this stripe and lip stripe bordered inferiorly by thin gray line. Measurements of two syntypes (male/female) (in mm): snout-vent lengt 54.3/75.2, tibia length 23.9/31.1, foot length 18.0/23.7, head length 18.8/22.0, head width 18.6/23.8, interorbital distance 5.2/8.1, internarinal distance 4.1/5.1, eyelid length 4.2/5.7, eye diameter 6.1/8.3, tympnamum diameter 3.2/4.2, ENOS 5.0/5.2 Coloration in life: Dorsal surfaces, face, and tympanum lime green; upper eyelid edged with red; venter gray, with pale yellow splotches; lower lip, supraanal fold, and tarsal fold white, edged with pale red; tubercles on flank white, tipped with red; tarsal fold white; ventral surfaces of hand and foot flesh- colored; axilla and concealed region of elbow pale yellow; groin, concealed surface of shank, tarsus, and thigh pale yellow-green with a hint of orange; anal region dark gray; paired anal tubercles pale yellow; finger and toe discs off-white; iris dark brown, almost black Larval morphology Following description is based on seven tadpoles. A representative larva at Stage 32 (Gosner 1960) with a SVL of 15.0 mm and total length of 42.5 mm. Body slightly deeper than wide, deepest and widest at two-thirds the length of the body; top of head slightly convex; snout rounded in lateral profile; snout rounded in dorsal view; nostrils dorsolateral; internarial distance slightly greater than width of oral disc; eyes dorsolateral and directed laterally; spiracle a flap-like tube, ventral and sinistral to midline; spiracular opening at a point about midlength of the body; mouth anteroventral; cloaca1 tube short, dextral to base of caudal fin; caudal musculature slender, tapering gradually to posterior end of fin; myomeres weakly developed; at midlength of the tail the depth of the caudal musculature slightly less than depth of ventral fin, but greater than depth of dorsal fin; caudal musculature extending to tip of tail; dorsal fin shallow anteriorly, not extending onto body; dorsal fin deepest at two-thirds its length from anterior; ventral fin deepest at its midlength. Mouth relatively small, with a shallow lateral fold; medial portion of upper lip lacking papillae; elsewhere, papillae present in one or two rows along borders; upper beak broadly curved and uniformly serrate; lower beak V-shaped and uniformly serrate; two upper and three lower rows of denticles; upper rows of same length; second upper row broadly interrupted medially; three lower rows of denticles uninterrupted; first two lower rows about same length; third row about onehalf as long as upper two; denticles of third row smaller and fewer in number. In life, dorsum transparent with gold and black pigments; lateral surfaces gold; venter transparent, with some gold pigment anteriorly; tail clear with fine distribution of melanophores; area above eye heavily pigmented with gold; iris white with black and gold flecks. In preservative, sides and top of head and body translucent, with scattered melanophores; intense concentration of melanophores covering gut, and obscuring view of intestines; caudal musculature flesh-colored; dorsal and ventral fins transparent, with fine distribution of melanophores in posterior one-half of dorsal and ventral fins, but not extending to tip of tail.

LC. Least Concern.

Phyllomedusa boliviana is a species of frog in the subfamily Phyllomedusinae. It is found in Argentina, Bolivia, and Brazil (west of Mato Grosso and Rondônia States). Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist montane forests, intermittent freshwater marshes, and ponds. It is threatened by habitat loss.