King or royal family? Testing for species boundaries in the King Cobra, Ophiophagus hannah (Cantor, 1836), using morphology and multilocus DNA analyses

Abstract

In widespread species, the diverse ecological conditions in which the populations occur, and the presence of many potential geographical barriers through their range are expected to have created ample opportunities for the evolution of distinct, often cryptic lineages. In this work, we tested for species boundaries in one such widespread species, the king cobra, Ophiophagus hannah (Cantor, 1836), a largely tropical elapid snake distributed across the Oriental realm. Based on extensive geographical sampling across most of the range of the species, we initially tested for candidate species (CS) using Maximum-Likelihood analysis of mitochondrial genes. We then tested the resulting CS using both morphological data and sequences of three single-copy nuclear genes. We used snapclust to determine the optimal number of clusters in the nuclear dataset, and Bayesian Phylogenetics and Phylogeography (BPP) to test for likely species status. We used non-metric multidimensional scaling (nMDS) analysis for discerning morphological separation. We recovered four independently evolving, geographically separated lineages that we consider Confirmed Candidate Species: (1) Western Ghats lineage; (2) Indo-Chinese lineage (3) Indo-Malayan lineage; (4) Luzon Island lineage, in the Philippine Archipelago. We discuss patterns of lineage divergence, particularly in the context of low morphological divergence, and the conservation implications of recognizing several endemic king cobra lineages.

In Vitro neurotoxicity and myotoxicity of Malaysian Naja sumatrana and Naja kaouthia venoms: Neutralization by monovalent and Neuro Polyvalent Antivenoms from Thailand

“…kaouthia and king cobra ( Ophiophagus hannah ) venoms [ 39 , 40 ]. This finding is expected as the king cobra is classified in a different genus, and it was recently reported that there could be multiple species of king cobra [ 41 ]. Densitogram of N .…”

“…Incapability of KCAV in recognizing N. kaouthia venom proteins in western blot is likely to be due to interspecies variation in venom toxin composition between N. kaouthia and king cobra (Ophiophagus hannah) venoms [39,40]. This finding is expected as the king cobra is classified in a different genus, and it was recently reported that there could be multiple species of king cobra [41]. Densitogram of N. sumatrana venom blots that were incubated with NPAV and CAV showed a similar number of peaks, which indicates similar toxin-antibody binding capabilities.…”

High-Voltage Toxin’Roll: Electrostatic Charge Repulsion as a Dynamic Venom Resistance Trait in Pythonid Snakes

“…It is conspicuous that the two Asian species ( P. bivittatus and P. brongersmai ) have the highest levels of positive charges within the orthosteric site, which suggests a stronger predatory pressure. While Naja (cobra) species are widespread snake-eating predators in both Africa and Asia, the much larger snake-eating predators in the Ophiophagus genus are only found in Asia [ 41 ]. The giant species P. sebae reaches sizes > 7 m and would therefore soon outgrow the prey size range of <2 m Naja species; the equally massive P. bivittatus would be in the prey size range of Ophiophagus species.…”

Himalayan upliftment and Shiwalik succession act as a cradle for divergence in Bengal monitor lizard Varanus bengalensis (Reptilia: Varanidae) in India

“…Genetic differentiation among V. bengalensis and other monitor lizard species from mitochondrial genes and microsatellite loci. level of morphological divergence (Shankar et al, 2021). Several phylogenetic studies on birds (Johansson et al, 2007;Martens et al, 2011), insects (Schmidt et al, 2012), amphibians (Hofmann et al, 2017) and reptiles (Xu et al, 2021) provide information and understanding regarding divergence in the Himalayan biota.…”

“…The diversification within Cyrtodactylus allowed exploration of the India–Asia collision and provided insights into Himalayan biogeography (Agarwal et al., 2014). Another example of intraspecific differentiation is in the wide‐ranging king cobra, with four independently evolving genetic lineages yet a low level of morphological divergence (Shankar et al., 2021). Several phylogenetic studies on birds (Johansson et al., 2007; Martens et al., 2011), insects (Schmidt et al., 2012), amphibians (Hofmann et al., 2017) and reptiles (Xu et al., 2021) provide information and understanding regarding divergence in the Himalayan biota.…”