Evidence of hidden diversity and taxonomic conflicts in five stream fishes from the Eastern Zimbabwe Highlands freshwater ecoregion

Abstract

Stream fishes of the Eastern Afromontane region are among the least studied vertebrates in this region, despite the potential for harbouring cryptic diversity. The present study examined mitochondrial cytochrome oxidase subunit I (COI) sequence divergence in 153 specimens of stream fishes belonging to four genera and three families, [(Amphilius and Zaireichthys (Amphiliidae); Chiloglanis (Mochokidae); and Hippopotamyrus (Mormyridae)], in the Eastern Zimbabwe Highlands (EZH) freshwater ecoregion to explore the extent to which the current taxonomy conceals the ichthyofaunal diversity in the region. The General Mixed Yule Coalescent (GMYC) species delineation method identified 14 clusters within five currently recognised ‘species’ from the EZH ecoregion. Only one of these clusters represents a named species, while 13 of them represent candidate or undescribed species. Our results revealed that effective conservation of this region’s unique biota is limited by the incomplete knowledge of taxonomic diversity and inaccurate mapping of species distribution ranges.

Integrative taxonomy reveals hidden diversity in the southern African darters genus Nannocharax Günther 1867 (Characiformes: Distichodontidae)

“…Both approaches have been widely applied in a number of studies to reveal hidden diversity within morphologically defined species and also for delimitation of candidate species in taxonomic groups that have been poorly studied morphologically (e.g., Chakona et al, 2018;Crivellaro et al, 2017;Kordbacheh et al, 2017;Ottoni et al, 2019). The ultrametric tree for GMYC analysis was estimated in BEAST, and the same tree was used as input tree for the bPTP analysis.…”

Designation of a neotype for Enteromius pallidus (Smith, 1841), an endemic cyprinid minnow from the Cape Fold Ecoregion, South Africa

“…These sequences were deposited in GenBank: neogenetype (MK900662) and topogenetype (MK900663). DNA extraction, PCR and sequencing methods follow Chakona et al (2018).…”

An integrative taxonomic review of the Natal mountain catfish, Amphilius natalensis Boulenger 1917 (Siluriformes, Amphiliidae), with description of four new species

“…Our analysis S1). Fifty of these sequences were produced during our study and the study of Chakona et al (2018), with an additional 18 sequences downloaded from BOLD (Supporting Information Table S1). The model of sequence evolution that best fitted the data was determined using the corrected Akaike information criterion in JModelTest v 2.1 (Darriba & Posada, 2014) as implemented in the CIPRES Science Gateway (Miller et al, 2010).…”