A novel multilocus phylogenetic estimation reveals unrecognized diversity in Asian horned toads, genus Megophrys sensu lato (Anura: Megophryidae)

Abstract

The horned toad assemblage, genus Megophrys sensu lato, currently includes three groups previously recognized as the genera Atympanophrys, Xenophrys and Megophrys sensu stricto. The taxonomic status and species composition of the three groups remain controversial due to conflicting phenotypic analyses and insufficient phylogenetic reconstruction; likewise, the position of the monotypic Borneophrys remains uncertain with respect to the horned toads. Further, the diversity of the horned toads remains poorly understood, especially for widespread species. Herein, we evaluate species-level diversity based on 45 of the 57 described species from throughout southern China, Southeast Asia and the Himalayas using Bayesian inference trees and the Generalized Mixed Yule Coalescent (GMYC) approach. We estimate the phylogeny using both mitochondrial and nuclear DNA data. Analyses reveal statistically significant mito-nuclear discordance. All analyses resolve paraphyly for horned toads involving multiple strongly supported clades. These clades correspond with geography. We resurrect the genera Atympanophrys and Xenophrys from the synonymy of Megophrys to eliminate paraphyly of Megophrys s.l. and to account for the morphological, molecular and biogeographic differences among these groups, but we also provide an alternative option. Our study suggests that Borneophrys is junior synonym of Megophrys sensu stricto. We provide an estimation of timeframe for the horned toads. The mitochondrial and nuclear trees indicate the presence of many putative undescribed species. Widespread species, such as Xenophrys major and X. minor, likely have dramatically underestimated diversity. The integration of morphological and molecular evidence can validate this discovery. Montane forest dynamics appear to play a significant role in driving diversification of horned toads.

Molecular, morphological and acoustic assessment of the genus Ophryophryne (Anura, Megophryidae) from Langbian Plateau, southern Vietnam, with description of a new species

“…They provided compelling evidence (recent diversification, insufficient morphological or biological distinction of major clades) for the consideration of Megophryinae to be treated as a single genus, Megophrys , with seven sub-clades (including Ophryophryne ) being treated as subgenus level taxa. Their phylogenetic analyses provided strong support for the sister taxa relationship of Ophryophryne and a clade corresponding to Panophrys (previously considered a synonym or subclade of Xenophrys , e.g., Delorme et al 2006, Chen et al 2017). …”

“…Data on morphology and taxonomy of Ophryophryne are also available from the following literature: O. microstoma (Bourret 1942, Liu and Hu 1962, Yang 1991, Ye et al 1993, Fei et al 1999, 2009, 2010, 2012, Zhang and Wen 2000, Ohler 2003, Bain et al 2007, Yang 2008), O. pachyproctus (Kou 1985, Yang 1991, Ye et al 1993, Fei et al 1999, 2009, 2010, 2012), O. poilani (Bourret 1937, 1942, Ohler 2003). However, due to the considerable undiagnosed diversity within Megophryidae (Chen et al 2017, Mahony et al 2017), where available, we relied on the examination of type specimens, topotypic material and/or original species descriptions. Only characters verified on all specimens in the type series and referred specimens are used to represent the new species in the comparison and diagnosis sections.…”

“…A recent phylogenetic study on Megophryinae by Chen et al (2017) provides new insights on evolutionary relationships within this group, indicating contrasting (though poorly supported) phylogenetic positions of Ophryophryne in their multilocus nuclear-gene based phylogeny and matrilineal mtDNA genealogy. Chen et al (2017) preliminarily recognized Ophryophryne as one of the five monophyletic genera within Megophryinae ( Ophryophryne , Brachytarsophrys , Xenophrys , Atympanophrys and Megophrys ). However, Mahony et al (2017) provides an alternative hypothesis based on extensive morphological studies and a larger nuclear gene dataset.…”

A new species ofLeptobrachium(Anura, Megophryidae) from western Thailand

“…Due to the high unrecognized diversity and morphological similarity of many species within the family, molecular phylogenetic tools are crucial for studies of the group’s taxonomy, which currently remains in a constant state of flux (Matsui et al, 2010; Matsui, 2013; Poyarkov et al, 2015; Poyarkov et al, 2017; Chen et al, 2017; Chen et al, 2018). …”

A New Field Protocol for Determination of Forest Structure, Biodiversity and Heath Status by Means of GPS Tools: A Case Study from Gaza Forest

“…So far poor management of forests and urban trees may lead to losing tree population, diversity, health status and productivity. Tree population, age and biodiversity are important elements in the forest that determine its productivity growth, and health status [10]. It is well known in the literature that forest structure is categorized into four groups such as canopy trees, dominant trees, co-dominant trees, intermediate trees and suppressed trees.…”