Chocolatefoot Leaf Frog

Phasmahyla cochranae is a small leaf-frog; SVL varies from 28 mm to 37 mm in males and 41-46 mm in females. Snout outline rounded. Tympanum distinct below, hidden above, measuring 1/2 of the eye diameter. Eyes moderately large, directed foward. Pupils vertical. Supratympanic fold distinct only from posterior edge of tympanum to sholder. Vocal sac is subgular or absent. Nostrils at the tip of snouts, placed laterally and directed backward. Finger discs distinct. Fingers free, webbing absent. Finger subarticular tubercles moderately developed. Nuptial pad is present in males, on inner side of the first finger. Forearm fold distinct, glandular, not scalloped. Subarticular tubercles presents. General dorsal texture smooth-glandular; throat and chest weakly glandular; belly glandular. Toe discs distinct. Inner metatarsal tubercle ovoid; heel with small calcar. Dorsal color pattern bright green, but can vary depending on the day time, to brown or redbrick, with scattered small white spots. Concealed surface of sides, arms, legs, finger and toes orange or yellowish with irregular rounded purple or red chocolate spots. This species shows some sexual size dimorphism, with males being lighter and smaller than females (Bokermann 1966; Heyer et al. 1990). Cruz (1990) described the cranial osteology of a closely related species, P. guttata. The tadpole was described by Bokermann (1966), Cruz (1982) and Heyer et al. (1990): LTRF 1/2(1) or 0/1(1). Total length 43 mm at Gosner stage 36. Body sub-cylindrical in dorsal view and triangular in lateral view. Snout broad in dorsal outline. Eyes dorsolateral, laterally directed. Nares dorsolateral, small and rounded. Spiracle ventral, with elliptical opening, directed posteriorly. Vent tube long and dextral, not fused with the fin. Tail slightly higher than body. Dorsal fin originates at the posterior third of the body. Dorsal and ventral fins arched. Oral apparatus anteroventral, with a semicircular funnel-shaped dermal fold superiorly bilobed, showing two distinct sizes of papillae. Jaw sheaths moderately developed and finely serrated, upper jaw sheath V-shaped. Caudal muscle reaching tail tip. General coloration gray-brownish, fins transparent, with flecks (Altig and McDiarmid 1999).The diploid number is equal to 26 (Duellman 1968). The genus is named in reference to the typical walking, resembling that of the insects of the order Phasmatodea (Cruz 1990). The specific epithet cochranae is in homage to Dr. Doris. M. Cochran (USNM) (Bokermann 1966). D´heursel (2004) described the internal oral features of the larva of this species.

Phasmahyla cochranae is found in Brazil, within eastern Minas Gerais, Southwestern Rio de Janeiro and eastern São Paulo states. It occurs along forest streams associated with the Atlantic Rainforest at elevations up to 800 m asl.

Phasmahyla cochranae lives along riparian vegetation of forest streams (Ribeiro et al. 2005). It is commonly found at very low abundance, usually no more than 3 individuals in a chorus (Heyer et al. 1990), it occurs from October to April (Cardoso et al. 1989). The eggs are deposited in a gelatinous mass inside envelopes of folded leaves over swift streams; hatchling tadpoles drop into the currents and drift downstream to deeper and quieter pools along montane streams, where frequently they form schools near the water surface at night (Bokermann 1966; Haddad and Sazima 1992, reproductive mode 25 of Haddad and Prado 2005). The development takes about 5 months (Bertoluci 1997; Provete pers. obs.). The mean number of eggs in the clutch is 32, the general color is cream white (Bokermann 1966; Haddad 1991). Tadpoles of this species are neustonic and forage at the water surface (Altig and McDiarmid 1999). The tadpoles are found with highest abundance between September and December (Bertoluci 1997). During the day they take refuge under stones, logs and other debris (Bokermann 1966).

Its range is within protected areas, like the Parque Estadual Nova Baden, Parque Estadual de Ibitipoca, in the state of Minas Gerais, and Parque Nacional da Serra da Bocaina, Parque Municipal do Itapetinga, Serra do Japi and, Estação Biológica de Boracéia, in the state of São Paulo, and in Parque Nacional de Itatiaia, in the state of Rio de Janeiro. Decreasing according to IUCN (2008).

não floresceu

DiagnosisA small species related to P. guttata, characterized by dark reddish chocolate markings on the concealed surfaces of arm, forearm, both sides of femur, tibia and tarsi, dorsal surface of fingers and toes, and sides of body. Phasmahyla cochranae differs from P. guttata in having less bulging eyes in both living and preserved specimens, the canthus rostralis less curved inward when viewed from above, a more rounded head margin when viewed from below, a greater distance between the inferior boarder of the eye and the margin of the upper lip, and in the color pattern: In P. cochranae the red chocolate markings are present on the dorsal surface of the fingers and toes, concealed parts of the fore and hind limbs, and in guttata these markings are absent on arms and tarsi and reduced to one or two or absent on the femur, tibia, and forearm.

Known from the Mar and Mantiqueira Mountain Ranges, in the states of São Paulo, Rio de Janeiro, and Minas Gerais, Brazil.

herbacea

perene

Taninos

Description of holotype Head slightly depressed, its width (15.5 mm.) nearly one-third the snout-vent length (46.0 mm.). Snout nearly vertical in lateral profile and with the tip truncated when viewed from above. Nostrils at tip of snout, placed laterally and directed backward. Canthus well marked, viewed from above very concave; loreal region slightly concave. Eyes of moderate size, projected anterolaterally, its horizontal diameter (4.5 mm.) equal to the distance from eye to nostril. Interorbital space nearly twice as broad as upper eyelid. Tympanum indistinct, its horizontal diameter (2.3 mm.) nearly half the size of eye. Supratympanic fold visible posteriorly only to tympanum. Vomerine teeth absent. Tongue elongate, free on the posterior half and notched behind. Forelimbs long and slender. Arm very slender, forearm normal. Fingers well developed, a little broader than the last joint; subarticular tubercles well developed; an inner carpal tubercle on bases of first finger. A poorly developed dermal ridge along external margin of forearm. Hind limbs short; tibiotarsal articulation reached the eye with the adpressed hind limb; femur very slender, a little longer than tibia; toes well developed, with a rudiment of membranae between the outer three; first toe a little shorter than second; discs poorly developed, a little broader than the last joint; subarticular tubercles well developed; a tarsal tubercle on bases of first toe. A poorly developed dermal appendage on the tibiotarsal articulation and a poorly developed dermal ridge along outer margin of tarsus. Skin of dorsal surface coarse with a few small warts. Ventral surface of limbs, except coxae, smooth; coxae and abdomen granular; gular region rugose. Coloration In preservative: Pale bluish gray above; ventral surface of limbs and body cream white; concealed parts of limbs and sides of body cream with chocolate markings. In life: Usually bright green above but occasionally purplish brown; ventral surface yellow-white; concealed surfaces of limbs and sides of body bright orange with reddish chocolate markings. Holotype.-An adult male 36 mm. snout-vent length, 14.0 mm. head width, 3.8 mm. horizontal diameter of eye and distance from eye to nostril, and 1.8 mm, diameter of tympanum. The vocal sac is subgular and a nuptial pad is present on inner side of first finger. In other respects it agrees with the holotype. Variation.-The paratypes agree in general respectts with holotype and allotype; the five females range from 41 to 46 mm, with an average of 43 mm. The 16 males range from 33 to 37 mm. with an average of 35.3 mm. There are few differences in color pattern: Certain specimens present the dark chocolate markings of the side of the body and the concealed parts of the limbs are partially or completely confluent. Larval Morphology Larvae from Serra da Bocaina and Campos do Jordão attain a maximum size of 55.0 mm. They are olive brown above and silvery white below. The tail fin has no chromatophores but only dark markings of the blood vessels. The body is of irregular triangular shape and occupies one-third of the total length. The fin is broader than the body and terminates in a long point of the flagellate type. The spiraculum is ventral and slightly sinistral; the anal tube is median with the opening directed to the right side. The funnel-shaped structure of the mouth is anterodorsal, semicircular, and superiorly bilobed. The inferior margin is not actually notched but the margin is waved or crenulated, depending on preservation. The maxilla is trilobate with serrated margins. Superiorly there is a dermal ridge without teeth. The mandible is V-shaped with serrated margins. Inferiorly there are two series of teeth: the internal divided and the external simple. Several small rounded glands are regularly distributed through the funnel and two larger elongate glands are on each side of the mouth. The tadpoles also present a few differences with P. guttata: the tail fin is broader in P. cochranae, principally in fully grown specimens, and the body is also broader and higher. The upper tooth row is absent in P. cochranae and the lower rows have the teeth reduced or poorly developed.

Europa

LC. Least Concern.

Phasmahyla cochranae, sometimes called the chocolatefoot leaf frog, is a species of frog in the subfamily Phyllomedusinae. It is endemic to Brazil. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical moist montane forests, and rivers. It is threatened by habitat loss.