Lesser Snouted Tree-frog

This is a small hylid treefrog characterized by a snout-vent length ranging from 27 to 35 mm in males and 31 to 38 mm in females. It features a slightly elongated head with a prominent, subacuminate snout in dorsal view, which is rounded in profile—a distinct morphological trait that inspires its specific scientific name. Dorsal coloration is highly polymorphic, varying from shades of gray and beige to dark brown, frequently adorned with darker longitudinal bands or an irregular "Y" or "X" shaped marking on the interocular region. The skin on its dorsum is mostly smooth or finely granular, while the abdominal region displays a highly granular texture with a whitish or cream coloration. A key diagnostic character for its identification is the presence of vivid yellow or orange coloration with dark, blackish reticulations in the hidden areas of the groin and posterior thighs, visible only during jumping or stretching. Well-developed adhesive discs on the digits enable efficient vertical climbing on various natural and artificial surfaces.

Geographical distribution: This amphibian is widely distributed across the central and southern regions of South America. Its geographic range encompasses northern and central Argentina, the entirety of Paraguay, eastern Bolivia, western and southern Uruguay, and extensive territories in central, southern, and southeastern Brazil, spanning diverse biomes including the Chaco, Cerrado, and transitional zones of the Atlantic Forest.

Habitat: It occupies a broad spectrum of ecological niches, showcasing remarkable environmental plasticity. It is commonly found in semideciduous forests, flooded savannas, grasslands, and shrublands. Notably, this species is highly synanthropic, adapting seamlessly to human-modified landscapes and frequently colonizing urban gardens, greenhouses, and residential structures, where it seeks moisture and shelter in bathrooms, kitchens, and drainpipes.

Feeding: Its diet is opportunistic and strictly insectivorous, consisting of a wide array of small terrestrial and aerial arthropods. Primary prey items include dipterans, coleopterans, lepidopterans (both adults and larvae), hemipterans, hymenopterans, and various small spiders. It often hunts at night, utilizing artificial light sources in urbanized areas to capture insects attracted to the glow, maximizing its foraging efficiency.

Behavior: This treefrog is primarily nocturnal and arboreal. During the daytime, it shelters in microhabitats with high humidity, such as tree bark crevices, bromeliad axils, rock fissures, and human dwellings to prevent dehydration. It exhibits outstanding climbing performance due to its expanded digital pads and wet adhesion mechanisms. Its activity levels peak during the rainy season, during which males vocalize intensely from elevated perches to attract females.

Reproduction: The reproductive cycle is seasonal and highly dependent on rainfall during the warmer spring and summer months. Males aggregate around temporary pools, flooded pastures, ditches, and permanent lagoons, calling from emergent vegetation or muddy banks near the water´s edge to attract mates. Following axillary amplexus, the female deposits egg masses that adhere to aquatic plants or float near the surface. Embryonic development is rapid, producing nektonic tadpoles with a yellowish-brown base body color, dark longitudinal stripes, and high caudal fins, allowing them to metamorphose quickly before ephemeral water bodies evaporate.

Conservation status: It is classified as Least Concern (LC) on the IUCN Red List of Threatened Species. This assessment is justified by its vast geographical distribution, exceptionally high tolerance to anthropogenic habitat modification, and stable, robust population trends across its entire range, with no major threats currently imperiling its long-term survival.