Carvalho's tree toad  (Dendrophryniscus carvalhoi)

Carvalho’s tree toad is classified as Endangered (EN) on the IUCN Red List (1).

Carvalho's tree toad (Dendrophryniscus carvalhoi) is a small, cryptically coloured amphibian endemic to the Atlantic forest of Brazil. It is named in memory of Professor Antenor Leitão de Carvalho, a respected herpetologist and ichthyologist of the National Museum of Rio de Janeiro (2).

Carvalho’s tree toad has a triangular-shaped head, with a ridge which runs from the above the eye to the tip of the snout. The back is covered in large, grainy bumps and an ‘X’-shaped spot pattern. The fore legs of Carvalho’s tree toad are slender, with enlarged tips to the fingers (2), although the more robust first finger is somewhat reduced on the male, and is covered in a thickened, hardened pad called a ‘nuptial pad’, which is used to clasp the female during breeding (3). The hind limbs are also slender, with comparatively small toes which are slight webbed (2).   

Carvalho’s tree toad is a rare amphibian which is only known from Santa Tereza and Fundao, in the Espírito Santo area of the Atlantic forest in Brazil (1) (4) (5).

Carvalho’s tree toad lives among leaf litter in primary and secondary Atlantic forest, at elevations of around 800 metres (1) (4).

Very little is known about the biology of Carvalho’s tree toad. The genus Dendrophryniscus contains eight species which are split into two groups based on their reproductive behaviour: the first group breeds in ponds, while the second lays its eggs in bromeliads (a family of flowering plants that are mainly native to the tropical Americas), in which the tadpoles then develop (2) (3). Carvalho’s tree toad is thought to belong to the latter group (1) (2) (3) (4).

Carvalho’s tree toad, like many other amphibians in the Atlantic forest, is under threat from habitat loss because of deforestation, conversion to agricultural land, livestock grazing and human settlement (1) (4) (6). The Fundao population of Carvalho’s tree toad in particular is threatened by expanding coffee cultivation in this area (4).

The chytrid fungus (Batrachochytrium dendrobatidis) is also an important cause of amphibian declines elsewhere in the world, and although it has yet to be documented in Brazil, it is likely to pose a severe threat in future if it continues to spread (6).

Carvalho’s tree toad is found in protected areas in the Caparao National Park and the Santa Teresa Biological Reserve (7). It may also occur in the Estacion Biólogica Santa Lucia, and Reserva Biólogica Augusto Ruschi, but this is not confirmed (1) (4).

Population declines of amphibians in Brazil are poorly documented and understood, largely because of a lack of knowledge about the biology and ecology, an incomplete knowledge of the threats facing these species, and a lack of population monitoring. All amphibian species found in the Atlantic forest, including Carvalho’s tree toad, would benefit from increased research (6).

To find out more about the conservation of the worlds amphibians, see:

• Amphibian Specialist Group:
  http://www.amphibians.org/ASG/Home.html

To read more about the worlds threatened amphibians, see:

• Stuart, S.N., Hoffmann, M., Chanson, J.S., Cox, N.A., Berridge, R.J., Ramani, P., and Young, B.E. (Eds.) (2008) Threatened Amphibians of the World. Lynx Edicions, Barcelona, Spain; IUCN, Gland, Switzerland; and Conservation International, Arlington, Virginia, USA.

To discover more about the Atlantic forest, see:

• Conservation International:
  http://www.biodiversityhotspots.org/xp/hotspots/atlantic_forest/Pages/default.aspx
• The Nature Conservancy:
  http://www.nature.org/wherewework/southamerica/brazil/work/art5080.html
• WWF:
  http://wwf.panda.org/about_our_earth/ecoregions/atlantic_forests.cfm