Seven new species of Night Frogs (Anura, Nyctibatrachidae) from the Western Ghats Biodiversity Hotspot of India, with remarkably high diversity of diminutive forms

Abstract

The Night Frog genus Nyctibatrachus (Family Nyctibatrachidae) represents an endemic anuran lineage of the Western Ghats Biodiversity Hotspot, India. Until now, it included 28 recognised species, of which more than half were described recently over the last five years. Our amphibian explorations have further revealed the presence of undescribed species of Nights Frogs in the southern Western Ghats. Based on integrated molecular, morphological and bioacoustic evidence, seven new species are formally described here as Nyctibatrachus athirappillyensis sp. nov., Nyctibatrachus manalari sp. nov., Nyctibatrachus pulivijayani sp. nov., Nyctibatrachus radcliffei sp. nov., Nyctibatrachus robinmoorei sp. nov., Nyctibatrachus sabarimalai sp. nov. and Nyctibatrachus webilla sp. nov., thereby bringing the total number of valid Nyctibatrachus species to 35 and increasing the former diversity estimates by a quarter. Detailed morphological descriptions, comparisons with other members of the genus, natural history notes, and genetic relationships inferred from phylogenetic analyses of a mitochondrial dataset are presented for all the new species. Additionally, characteristics of male advertisement calls are described for four new and three previously known species. Among the new species, six are currently known to be geographically restricted to low and mid elevation regions south of Palghat gap in the states of Kerala and Tamil Nadu, and one is probably endemic to high-elevation mountain streams slightly northward of the gap in Tamil Nadu. Interestingly, four new species are also among the smallest known Indian frogs. Hence, our discovery of several new species, particularly of easily overlooked miniaturized forms, reiterates that the known amphibian diversity of the Western Ghats of India still remains underestimated.

<b><I>Nyctibatrachus mewasinghi</I>, a new species of night frog (Amphibia: Nyctibatrachidae) from Western Ghats of Kerala, India</b>

“…nov. Krutha et al and morphological information and provided novel behavioral observations. This was followed by discovery of a new mud packing behavior and description of a new species by Gururaja et al (2014) and seven new species of small sized night frogs by Garg et al (2017). All these papers elucidated our limitations in the knowledge of amphibian diversity in Western Ghats biodiversity hotspot.…”

“…Thus to remove the effect of size, morphometric data were normalized by expressing measurements as a ratio of SVL. Apart from the N. kempholeyensis and N. athirappillyensis comparative material (see Appendix 1) we also used data from Biju et al (2011) and Garg et al (2017). Discriminant analysis (DA) was performed to understand whether related species of Nyctibatrachus form significantly different clusters (Huberty & Olejnik 2006).…”

“…Although originally considered as a member of the family Ranidae by Boulenger (1882), based on molecular phylogenetic studies by Roelants et al (2004), Bossuyt et al (2006) and Frost et al (2006), this genus is now placed under the family Nyctibatrachidae. The Western Ghats endemic genus Nyctibatrachus has 35 known species (Garg et al 2017).…”

The herpetological collection of the Institute for biological research 'Siniša Stanković', University of Belgrade

“…This is not surprising, because digitalization of natural history collections started already in the 1970s (Graham et al 2004), and there are attempts at making a transnational network of museum repositories (www.biocase.org). Nevertheless, the importance of the existing biological collections (storing billions of specimens - Graham et al 2004) rises in modern times, when we witness both the extinctions and discoveries of numerous species and various environmental stresses at the global level (Winker 2004, Garg et al 2017. A recent illustration of how important collections can be is the loss of one (Warrell et al 2010).…”

Vocalisation and its association with androgens and corticosterone in a night frog (Nyctibatrachus humayuni) with unique breeding behaviour

“…The Bombay night frog, Nyctibatrachus humayuni (Family: Nyctibatrachidae), is one of the 35 species of night frogs described from India (Garg, Suyesh, Sukesan, & Biju, ). The frog is endemic to montane and submontane streams of the Western Ghats and exhibits unique courtship and breeding behaviour (Gramapurohit, Gosavi, & Phuge, ; Willaert et al, ).…”