Scinax onca: A new species of Treefrog from Brazil.

Treefrogs of the genus Scinax are found from from Mexico in the North to central Argentina and Uruguay in the South. Over 70 species of this genus have been described,including 28 species from Amazonia, making it one of the largest genera of Treefrogs, with many undescribed species still thought to be present in less well explored areas. One such area is the Purus-Madeira Interfluve (area between the Purus and Madiera rivers, both tributaries of the Amazon), of Amazonas State in Brazil, where seven putative undescribed species are thought to be present. This area is currently crossed by an abandoned section of highway, though there have been recent plans to redevelop this road, raising concerns about logging and habitat loss, a major cause of species decline and loss for a variety of groups, including Treefrogs.

In a paper published in the journal ZooKeys on 4 October 2017, Miquéias Ferrão of the Programa de Pós-Graduação em Ecologia at the Instituto Nacional de Pesquisas da Amazônia, Jiří Moravec of the Department of Zoology at the National Museum in Prague, Rafael de Fraga, also of the Programa de Pós-Graduação em Ecologia at the Instituto Nacional de Pesquisas da Amazônia, Alexandre Pinheiro de Almeida of the Programa de Pós-Graduação em Zoologia at the Universidade Federal do Amazonas, Igor Luis Kaefer of the Instituto de Ciências Biológicas, also at the Universidade Federal do Amazonas, and Albertina Pimentel Lima of the Coordenação de Biodiversidade at the Instituto Nacional de Pesquisas da Amazônia, describe a new species of Scinax from the middle to southern part of the Purus-Madeira Interfluve.

The new species is named Scinax onca, where 'onca' refers to the Jaguar, Pantera onca, which was encountered numerous times during fieldwork in the Purus-Madeira Interfluve, and to the blotchy pattern of the species. Females of the species are larger than the males, reaching 35.5−40.4 mm, compared to 31.3−34.5 mm, and are variable in colouration, though generally brown and blotchy, and in addition are capable of changing colour to some extent, generally becoming darker and more blotchy when disturbed.

Colour in life of Scinax onca from the Purus-Madeira Interfluve, Brazilian Amazonia. (A)–(B), adult male from the kilometre 350 of the BR-319 highway, State of Amazonas, (C)–(D) adult female from municipality of Porto Velho, State of Rondônia, (E)–(F) adult female from the Floresta Estadual Tapauá Reserve, municipality of Tapauá, State of Amazonas. Photographs (A)–(D) and (F) were taken after transport of the specimens to the camp, while the image of (E) was taken immediately in the field. Ferrão et al. (2017).

The species was found at four localities, two in areas of closed forest with emergent trees (taller trees that rise above the tree canopy) in the central part of the Interfluve and two areas of open lowland rainforest with frequent Palm Trees in the southern part. They were encountered near temporary ponds following periods of heavy rain, where the males gathered on nearby plants to sing. Tadpoles of the species are ovoid in dorsal view, triangular in lateral view, and silvery-green in colour with large dark brown spots.

 Tadpole of Scinax onca from the middle Purus-Madeira Interfluve. Specimen collected at kilometre 350 of the BR-319 highway, municipality of Beruri, State of Amazonas, Brazil. From top to bottom: dorsal, ventral, and lateral views of preserved tadpole in developmental Stage 37. Scale bar 5 mm. Ferrão et al. (2017).

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Four new species of Treefrog from South America.

Many species of Amazonian Amphibians are considered to be highly threatened due to habitat loss, with the potential for the situation to become much worse due to climate change in the near future. This has led to increased efforts to understand the ecology and biodiversity of these groups, with the hope of implementing better conservation and species management plans. These studies have revealed a hidden diversity within many groups, where populations formerly assumed to be all one interbreeding species have been revealed to comprise a number of cryptic species, similar in appearance but genetically isolated from one-another.

In a paper published in the journal ZooKeys on 15 January 2014, Marcel Caminer of the Museo de Zoología at the Escuela de Biología at the Pontificia Universidad Católica del Ecuador and the Departamento de Biologia Evolutiva y Biodiversidad at the Museo Nacional de Ciencias Naturales in Madrid and Santiago Ron, also of the  Museo de Zoología at the Pontificia Universidad Católica del Ecuador describe four new species of Treefrog (Hylidae) from Ecuador and Peru. All are placed in the genus Hypsiboas, which already contains over 70 species.

The first new species described is named Hypsiboas almendarizae (Almendariz’s Treefrog), in honour of Ana Almendáriz, a distinguished Ecuadorian herpetologist who is curator of Herpetology in the Museo de Historia Natural Gustavo Orcés at the Escuela Politécnica Nacional del Ecuador. This is a cream or reddish, grayish or pale brown Treefrog occationally having darker markings. Adult males range from 34.31–44.56 mm and the females 37.80–51.94 mm. Its eyes have cream or creamy silver irises with a yellow or orange band at the top.

Adult male specimen of Hypsiboas almendarizae. Caminer & Ron (2014).

Hypsiboas almendarizae has been found on the eastern Andean slopes of Morona Santiago, Napo, and Tungurahua provinces in central and southern Equador, at altitudes of between 500 and 1950 m. They were predominantly found in pastures, pools and forest vegetation around rivers, roosting at night in vegetation 20-150 cm above the ground. Typically these areas had foothill or montane evergreen forests with a canopy 30 m above the ground. Much of the area inhabited by Hypsiboas almendarizae is under threat from human activity, particularly deforestation fueled by farming and cattle ranching, and Caminer & Ron recommend that it be assigned to the Near Threatened category on the International Union for the Conservation of Nature's Red List of Threatened Species.

Hypsiboas almendarizae, frontal view, showing the colouration of the iris. Caminer & Ron (2014).

The second new species described is named Hypsiboas maculateralis (the Stained Treefrog), in reference to the brown markings on its flank. This is a yellowish tan or cream Treefrog sometimes having darker bands on its back. Its flanks are white, pale blue or blue with dark brown blotches. Adult males were 31.86–39.17 mm long, the females 32.04–55.31 mm.

Adult male specimen of Hypsiboas maculateralis. Caminer & Ron (2014).

Hypsiboas maculateralis is found in the Amazon Basin of Napo, Orellana, Pastaza, and Sucumbíos provinces in Ecuador and Región de Madre de Dios in Peru, at altitudes of between 186 m and 354 m above sea-level. It was found in Amazonian moist forests and lowland evergreen forests, where the canopy reaches about 30 m, perching in vegetation 40-200 cm above the ground in areas of pasture or flooded forest. Its range is largely undisturbed by human activity, and Caminer & Ron recommend that it be assigned to the Least Concern category on the International Union for the Conservation of Nature's Red List of Threatened Species.

Adult female specimen of Hypsiboas maculateralis. Caminer & Ron (2014).

The third new species described is named Hypsiboas alfaroi (Alfaro’s Treefrog) in honour of Eloy Alfaro Delgado, president of Ecuador from 1897–1901 and 1906–1911 and considered to be the leader of the liberal revolution in Ecuador, who championed the separation of the church and state and modernization and and development of the nation's education, transport and communication systems. This is a creamy white, yellowish brown, reddish brown or brown Treefrog sometimes having bands or dots on its back. Its flanks are white, light blue or blue with dark brown spots or blotches. The males are 27.91–36.27 mm in length, the females 39.68–49.21 mm.

Adult female specimen of Hypsiboas alfaroi. Caminer & Ron (2014).

Hypsiboas alfaroi has been found in Napo, Orellana, and Sucumbíos provinces in the north Ecuadorian Amazon, and is probably also found in Peru, since it occurs close to the border. It was found at elevations of 176-350 m, in lowland evergreen forest and floodplain forest with canopies of about 30 m.  Its range is largely undisturbed by human activity, and Caminer & Ron recommend that it be assigned to the Least Concern category on the International Union for the Conservation of Nature's Red List of Threatened Species.

Adult male specimen of Hypsiboas alfaroi. Caminer & Ron (2014).

The final new species described is named Hypsiboas tetete (the Tetete Treefrog), in honour of the Tetete people, a Western Tucanoan indigenous people who formerly inhabited the Colombian and Ecuadorian Amazon and who were wiped out in the 1970s, largely due to the activities of the rubber industry. This is a pale yellowish tan to reddish brown Treefrog with a brown dorsal line. Its flanks are white with rounded or elongate brown markings. Males of this species reach 31.15–32.24 mm in length, females 45.33–45.85 mm.

Adult male specimen of Hypsiboas tetete. Caminer & Ron (2014).

Hypsiboas tetete was found in Provincia Napo in Ecuador and Región Loreto in Peru, both within the Amazon Basin, at altitudes of 180-420 m, though it is thought likely that this species has a wider distribution. It was found in lowland evergreen forests and moist forests, living in areas of flooded secondary forest 50-80 cm above the ground. It has a very limited known range, where environmental degradation due to human activity is limited but increasing, and therefore Caminer & Ron recommend that it be assigned to the Endangered category on the International Union for the Conservation of Nature's Red List of Threatened Species.

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