Allobates olfersioides is found in coastal forests of the Atlantic Domain from sea level to about 1000 masl. The species can be found from the north of the state of Alagoas to the south of the state of Rio de Janeiro (between
08 54 S and 23 00 S latitudinal degrees), potentially occurring in Parque Estadual do Rio Doce, state of Minas Gerais (Verdade and Rodrigues, 2007).
Habitat and Ecology
Allobates olfersioides is diurnal and lives on the forest floor of primary and secondary forests. The tadpoles hatch in humid terrestrial nests and are carried by their parents to puddles or small rivulets on the forest floor where they feed until metamorphosis. Males are known to carry tadpoles (ca Gosner stage 25) (Verdade and Rodrigues, 2007).
Gravid females were observed in February, April, August, and September, suggesting that reproduction is likely to occur throughout the year. In addition, they have been found to have both mature eggs and developing follicles in the ovaries, which again suggests that they may reproduce more than once during the reproductive season. Females were found to have a maximum of 11 mature eggs (ca 1.5 mm each) and a mean of 8 eggs (Verdade and Rodrigues, 2007). In Bahia, this species was found to have a strong association to bromeliads (Tinoco et al., 2008).
It used to be a very common species, but it has recently declined and is now absent from several historical localities in the states of Rio de Janeiro and Espírito Santo. The species still appears to be relatively common in northeastern Brazil (V. Verdade, pers. comm. 2008).
Habitat loss, due to deforestation and agricultural development, is ongoing, but may not have been severe enough to cause the declines that have been observed. In Bahia, this species was found to be one of the most threatened by environmental loss (Tinoco et al., 2008). Chytridiomycosis could be implicated in declines, specimens from Rio de Janeiro tested positive for chytrids (Carnaval et al., 2006).
It is known to occur in several protected areas, such as Parque Nacional da Serra da Bocaina. Research to determine the causes of the current decline is urgently needed.
Red List Status
Listed as Vulnerable because of a population decline despite its widespread distribution, its association to the highly threatened Atlantic rainforest biome, occurrence in areas affected by human population expansion, and geographic overlap with the chytrid's distribution in Brazil.
Based on morphological analyses, Verdade and Rodrigues (2007) allocate all Atlantic Forest species of Allobates to synonymy with Allobates olfersioides.
Vanessa Verdade 2010. Allobates olfersioides. The IUCN Red List of Threatened Species 2010: e.T55122A11255268. http://dx.doi.org/10.2305/IUCN.UK.2010-2.RLTS.T55122A11255268.en .Downloaded on 17 November 2018