Raorchestes chalazodes (Chalazodes bubble-nest frog, white-spotted bush frog, or Günther's bush frog) is a species of critically endangered frog in the family Rhacophoridae. Raorchestes chalazodes is a nocturnal and arboreal species found in the understorey of tropical moist evergreen forest and is endemic to the Western Ghats of India. The specific name chalazodes is composed of the Greek word χάλαζα (chalaza) meaning "lump" and -odes for the derived adjective, reflecting white granulation of the body.
The original holotype was collected in 1876 by Colonel Richard Henry Beddome in Travancore and given to Albert C. L. G. Günther. Before its rediscovery in 2011 in the Upper Kodayar Region in Tamil Nadu, the species was thought to be extinct. Raorchestes chalazodes make their oviposition sites in the internodes of the Ochlandra travancorica species of bamboo, where the adult male will take care of the egg clutch. Raorchestes chalazodes is also the only species in its genus that is reported to exhibit parental care. It is now considered critically endangered by IUCN.
Description
The overall body coloration of Raorchestes chalazodes is green with a purplish white ventral region and black-blue spots on the groin region. Some distinguishing characteristics of the species is a rounded snout, a lingual papilla on the tongue, and well-developed supernumerary tubercles. Raorchestes chalazodes also has moderate toe webbing. One of its most unique and distinctive traits is its eye: a black iris with golden patches.
Holotype
The holotype is an adult female collected in Travancore by Colonel Richard Henry Beddome, and given to Albert C. L. G. Günther, who described it. This specimen is 26 mm long with the hind limbs measuring 42 mm long. The dorsal surface is described as a uniform green, whereas the ventral surface is a yellowish-white color. The dorsal surface also has tubercles that look like white spots. These tubercles are presumed to be the reason Gunther named the species "chalazodes".
Habitat and distribution
Raorchestes chalazodes is found in the narrow region of the Western Ghats on the West Coast of peninsular India, where they are restricted to elevations over 1200 m. It lives in the tropical and moist evergreen forest understory. More specifically, Raorchestes chalazodes are found in the endemic understory of the Ochlandra travancorica bamboo that is found in the area. This bamboo forms a shrubby habitat that often forms impenetrable clumps next to stream banks, which offers protection.
Conservation
Habitat loss
Raorchestes chalazodes is currently classified as critically endangered by the most recent assessment by The IUCN Red List of Threatened Species in 2004. This assessment results from how the distribution of the species is severely fragmented and how the species experiences a continual decline in the extent and quality of its forest habitat.
The Ochlandra travancorica species of bamboo that Raorchestes chalazodes uses for oviposition sites is often harvested for use for biofuel and the manufacturing of paper and pulp. Because of this, Ochlandra travancorica has been severely depleted in the Western Ghats.
Conservation efforts
In a study on Raorchestes chalazodes in 2018, 43 egg clutches with male guardians were found in 5 km2 sampling site at Kalakad Mundanthurai Tiger Reserve. To help with conservation, a mapping of Ochlandra travancorica distribution to identify threatened areas that are not under protection is a vital first step of action. Additionally, there are more viable actions that can be taken to help with the conservation of Raorchestes chalazodes. Bamboo with smaller diameters can be harvested, or harvesting can be banned during the breeding season of Raorchestes chalazodes from May to November. Artificial oviposition sites that resemble those found in the wild can also be created.
Diet
Raorchestes chalazodes mainly consumes invertebrates such as insects and spiders, but have also been observed to eat other invertebrates such as molluscs. Specifically, Raorchestes chalazodes was observed consuming Satiella dekkanensis, a type of snail that does not possess a hard shell. Before the breeding season, adult male frogs will forage for large prey such as Satiella dekkanensis to prepare for the long period of caregiving.