Eleutherodactylus cystignathoides campi is a terrestrial frog and does not live close to water bodies. In spite of its terrestrial existence, this frog is very susceptible to desiccation as it loses water through its highly permeable skin. To avoid losing large amounts of water, this tiny frog has adapted to a nocturnal lifestyle remaining in hiding during the day. In its natural habitat, this frog is found underneath logs and debris, in caves, etc. where it can keep moist even during dry days. Around urban areas, E. cystignathoides campi appears on lawns, flower beds and gutters at night, hiding under any object which may provide moisture and shelter (e.g., boards, debris, etc.) during the day. Most tropical frogs (Leptodactylidae) show continuous reproduction throughout the year. However, those species closer to temperate areas may show some seasonality in their reproduction with peaks at specific times during the year. The natural populations of Eleutherodactylus cystignathoides campi reproduce during the months of April and May. However, the populations around the Houston area do not seem to be very active during those months. Their calls become more common as the summer months arrive (increased temperature and rain) and their breeding season probably extends into the fall. Female frogs may deposit several clutches per year with each clutch ranging from 5 to 12 large eggs (3 mm).

Identification

The Rio Grande Chirping frog, Eleutherodactylus cystignathoides campi, is a relatively small frog (1.6 - 2.5 cm). Males are generally smaller than females and have proportionately longer heads and larger tympani. The skin texture is usually smooth and the coloration is a combination of dark and light brown, grayish or yellowish olive patches. These frogs are characterized by a flat, elongated body with a pointed snout - a dark bar crosses the head on both sides through the eye to the nostril. The ventral skin is translucent facilitating the visualization of mature oocytes in females. As its name indicates, this frog produces high pitch cricket-like chirps sometimes followed by a trill. The chirp can be heard throughout the night as the males try to attract the females. Occasionally, it can be heard during the day when the humidity is very high.

Taxonomy

The Rio Grande Chirping frog belongs to the family Leptodactylidae, order Anura and class Amphibia. This family is composed of seven subfamilies, two of which occur in Australia, one in South Africa, and the rest in tropical and subtropical America. Members of this family show a wide range of reproductive modes from tadpoles to ovoviviparous with several modes in between. The genus Eleutherodactylus belongs to the subfamily Telmatobiinae which is subdivided into five tribes (Table). All the genera within the tribe Eleutherodactylini, including Eleutherodactylus, are direct developers: the embryo develops inside an egg and hatches as a small froglet.

Range