Trachycephalus mesophaeus - Milk Frog / Perereca-Leiteira (Hensel, 1867)

Amphibia: Lissamphibia: Batrachia: Anura: Neobatrachia: Hyloidea (Bufonoidea???): Hylidae: Hylinae: Lophiohylini (= Lophyohylini?)

Date: 3rd of December, 2017 at 08:01:44pm.
Location: Brazi, Santa Catarina, Benedito Novo (Lat: -26.77, Long: -49.36)

Trachycephalus mesophaeus is a frog in the class Amphibia, subclass Lissamphibia, superorder Batrachia, order Anura, suborder Neobatrachia, superfamily Hyloidea (Bufonoidea???), family Hylidae, subfamily Hylinae and tribe Lophiohylini (= Lophyohylini?).

They are endemic to Brazil and can be found in the states of Pernambuco, Alagoas, Sergipe, Bahia, Espírito Santo, Rio de Janeiro, Minas Gerais, São Paulo, Paraná, Santa Catarina (where this one was found) and Rio Grande do Sul.

They inhabit tropical and subtropical moist lowland forests, occurring in the edges and living near water sources, and Atlantic forests, also being found in an arboreal state or in tall or low Bromelia sp.. They can also be found in suburban habitats where there is plenty of wild vegetation and where this one was found.

They possess a lateral band on each side which connects between the eyes. They are incredibly sticky to the touch and can more or less attach themselves as some sort of natural glue in a defensive mechanism in which they can secrete a white substance, precisely where the name "milk frog" comes from. The reproductive season is often associated with strong rainfall, when males climb down from the trees or Bromelia sp. to vocalize to attract the females near idle waters.

This species was previously within the genus Phrynohyas, which was recently synonymized with Trachycephalus (Faivovich, et al., 2005). They are explosive breeders, and use temporary and permanent ponds to reproduce. The eggs are laid in clusters floating in the water.

The dorsal patterning that extends to a point postero-laterally on each side in the adult, bordered laterally by a yellow stripe skirted black from the eye to the end of the body, green bones and secreting glands of milky and viscous substances are defining traits to this species. They can be often found inside houses, which shows that they can have tolerance in anthropogenic habtiats.

Coleoptera and Blattodea are the most numerous and frequent prey choices of this frog, but Orthopterans are also regularly chosen. They seem to be opportunistic predators of invertebrates in general.

The sticky substance produced by this frog can easily engulf and kill tiny invertebrates. When I handled the Trachycephalus mesophaeus in the picture to remove it from the house, avoiding its death by the dogs, the sticky substance was incredibly adherent and hard to describe. It was like submerging your hand in a bucket of sticky slime or glue, and then taking it out and feeling the air drying the glue on your hand. Due to this, it managed to slip through my hands many times and I only managed to capture and release it after a while, which goes to show how potent this defensive mechanism is against predation. They are harmless.

Although their population status is of least concern, the population is decreasing, with no severe populational fragmentation for now.

This individual measured approximately 7cm from snout to vent.

Another common name is "golden-eyed tree frog".

Sources:

https://www.researchgate.net/publication/304081473_Trachycephalus_mesophaeus_Diet

http://www.scielo.br/pdf/bn/v12n4/a15v12n4.pdf

http://www.ufrgs.br/herpetologia/Anfíbios/Trachycephalus mesophaeus.htm

http://www.iucnredlist.org/details/summary/55822/0

http://www.checklist.org.br/getpdf?NGD139-10