Adult: Species description based on Donnelly and Guyer (1994), Duellman (2001), and Savage (2002). A small treefrog with a protruding snout (males to 38 mm, females to 40 mm). Breeding males turn brilliant yellow, with bright yellow-orange vocal sacs. Dorsal: The dorsum is yellowish, sometimes with green or light brown undertones. Some darker markings are usually present on the dorsum, and the arms and legs are also usually barred. The skin is generally smooth, or may appear a little bumpy. Ventral: The ventral coloration varies from cream to yellow to orange. The throat region is usually yellow. Concealed surfaces: The rear surfaces of the thighs are greenish-yellow. Distinguishing characteristics: The bones of Scinax elaeochrous are dark green. Eye: The eye is golden, with a coppery, bronzy or silvery cast.
Breeding season: Breeding occurs at ponds during the rainy season (Savage 2002). Large choruses form just after the first big rains (Duellman 1970, Donnelly and Guyer 1994). Egg: Eggs are laid in masses near or attached to pond vegetation (Duellman 1970). Tadpole: Tadpoles have compressed bodies with a moderately long tail and moderate tail fins (Savage 2002). The body is light yellowish brown with grey spots that extend onto the tail (Savage 2002). A diffuse brown stripe runs through the eye (Savage 2002). The ventral surface is pale (Savage 2002).
Habitat: Lowland and premontane forest to 1200 m. Call: A series of short "waaks" (Duellman 1970). Karyotype: 2N = 24 (Anderson 1991) Type locality: east foot of mountains near Sipurio (Costa Rica)