Observation on rapid physiological color change in Giant tree frog Rhacophorus smaragdinus (Blyth, 1852) from Namdapha Tiger Reserve, Arunachal Pradesh, India

Kailash Chandra,Basudev Tripathy,Arajush Payra,Deepak CK

doi:10.3897/herpetozoa.32.e36023

Abstract

Many poikilotherms have the ability to change body color for homeostatic regulation, conspecific communication or predator deterrence. Physiological color change is a rapid, reversible mode of color change regulated by neuromuscular or neuroendocrine system and has been observed in several anuran species. Here we report the occurrence of physiological color change in the tree frog Rhacophorussmaragdinus (Blyth, 1852) (Amphibia, Anura, Rhacophoridae) for the first time from Namdapha Tiger Reserve, Arunachal Pradesh, India. Probable proximate causes of the behavior are discussed along with an overview of physiological color change in species of the family Rhacophoridae and nature of color change observed.

Highlights

The ability to change body coloration is widespread among poikilotherms and is displayed by a diverse group of animals including cephalopods (Norman 2000, Hanlon 2007), crustaceans (Thurman 1988), insects (Hinton and Jarman 1972, Filshie et al 1975), fishes (Kodric-Brown 1998), amphibians (King et al 1994, Garcia and Sih 2003), and reptiles (Cooper and Greenberg 1992)
Based on the mechanism involved, color change can be of two types: (i) morphological color change, which involves changes in morphology and density of pigment-containing cells in the dermis and occurs at relatively longer time scales spanning from days to months (Sugimoto 2002), and (ii) physiological color change, which involves dispersion or aggregation of pigment granules within chromatophores and occurs at shorter time scales ranging from milliseconds to hours (Thurman 1988, Nordlund et al 1998)
It is unlikely that the response had any homeostatic function, as ambient temperature conditions before and after the capture of individual were not significantly different

Summary

Introduction

The ability to change body coloration is widespread among poikilotherms and is displayed by a diverse group of animals including cephalopods (Norman 2000, Hanlon 2007), crustaceans (Thurman 1988), insects (Hinton and Jarman 1972, Filshie et al 1975), fishes (Kodric-Brown 1998), amphibians (King et al 1994, Garcia and Sih 2003), and reptiles (Cooper and Greenberg 1992).Based on the mechanism involved, color change can be of two types: (i) morphological color change, which involves changes in morphology and density of pigment-containing cells (chromatophores) in the dermis and occurs at relatively longer time scales spanning from days to months (Sugimoto 2002), and (ii) physiological color change, which involves dispersion or aggregation of pigment granules within chromatophores and occurs at shorter time scales ranging from milliseconds to hours (Thurman 1988, Nordlund et al 1998). Key Words anuran behavior, reversible color change, camouflage, physiological stress, thermoregulation, Rhacophoridae, Rhacophorus maximus, Theloderma, Raorchestes, Pseudophilautus

Results

Conclusion