A new species of cryptic Bush frog (Anura, Rhacophoridae, Raorchestes) from northeastern Bangladesh

Abstract

Raorchestes is a speciose genus of bush frogs with high diversity occurring in the Western Ghats of India. Relatively fewer species have been recorded across India, through Bangladesh, southern China, into Vietnam and Peninsular Malaysia. Many bush frogs are morphologically cryptic and therefore remain undescribed. Here, a new species, Raorchestes rezakhanisp. nov., is described from northeastern Bangladesh based on morphological characters, genetics, and bioacoustics. The 16S rRNA gene distinguished this species from 48 known species of this genus. Bayesian Inference and Maximum Likelihood analyses indicated that the new species was most similar to R. tuberohumerus, a species found in the Western Ghats, and to R. gryllus, a species found in Vietnam. Bioacoustics indicated that their calls were similar in pattern to most Raorchestes species, although number of pulses, duration of pulses, pulse intervals and amplitude differentiated it from a few other species. It is suggested that northeastern India, Bangladesh, northern Myanmar, and southern China represent important, relatively unexplored areas that could yield additional species of Raorchestes. Since many remaining habitat patches in Bangladesh are under severe threat from deforestation, efforts should be made to protect these last patches from further degradation.

Amphibians and reptiles from Lawachara National Park in Bangladesh

“…Theloderma baibungense and Chikila fulleri are also newly reported from the country; these species were originally sighted by Tania Khan and are published here for the first time. Raorchestes rezakhani, a species still undescribed when we first encountered it in 2015, has now been described by other researchers (Al-Razi et al 2020).…”

“…comm.). Other researchers collected genetic samples from two male Raorchestes frogs in LNP and found them to represent a novel species, R. rezakhani (Al-Razi et al 2020). Habitat.…”

First Detection of Batrachochytrium dendrobatidis in Wild Frogs from Bangladesh

“…The distribution and prevalence of Bd fungus in South and South-East Asia will significantly contribute to the global distribution pattern of the fungus since these regions host more than 1,000 amphibian species including over 200 endemic species (Molur 2008) and more species presently being described (Howlader 2016;Saikia and Sinha 2019;Nguyen et al 2020;Razi et al 2020;Yao Li 2020). Swei et al (2011) completed a comprehensive survey where the sampling sites spanned 15 South and South-East Asian countries.…”

“…More recently Rahman et al (2020) revealed that Bd-suitable environmental conditions are widely distributed across Asia. As part of the Indo-Burma and the Himalayan biodiversity hotspots, Bangladesh hosts 50 amphibian species including new species discoveries on a regular basis (Howlader 2016;Razi et al 2020). A comprehensive species assessment including cryptic species may contribute to increasing the total number of amphibian fauna in the country.…”