Open AccessAfrican Herald snakes, Crotaphopeltis , show population structure for a widespread generalist but deep genetic divergence for forest specialists
Author(s) -
Engelbrecht Hanlie M.,
Branch William R.,
Greenbaum Eli,
Burger Marius,
Conradie Werner,
Tolley Krystal A.
Publication year - 2020
Publication title -
journal of zoological systematics and evolutionary research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.769
H-Index - 50
eISSN - 1439-0469
pISSN - 0947-5745
DOI - 10.1111/jzs.12361
Subject(s) - biology , generalist and specialist species , allopatric speciation , ecology , phylogeography , range (aeronautics) , genetic structure , coalescent theory , pantropical , genetic divergence , ecological niche , rainforest , population , species distribution , habitat , genetic diversity , phylogenetic tree , genus , genetic variation , sociology , gene , composite material , biochemistry , materials science , demography
The African colubrid snake genus Crotaphopeltis currently comprises six species and occurs throughout sub‐Saharan Africa. The most widespread of these, Crotaphopeltis hotamboeia , inhabits most biomes, aside from rainforest and hyper‐arid regions, and its catholic niche has presumably facilitated substantial gene flow. Despite this, the geographical range is large enough that ecological or physical barriers might exist, facilitating allopatric diversification. In contrast, most of the other species are habitat specialists with limited distributions (e.g., Crotaphopeltis tornieri ) and would be expected to show strong genetic structure. We therefore examined species boundaries within Crotaphopeltis in a phylogenetic context using five markers ( 16S , cyt b , ND4 , c‐mos , and RAG‐1 ) for four of the six species. Species delimitation methods included two coalescent‐based and one barcoding approach. Widespread geographical sampling of C. hotamboeia allowed examination of genetic structuring across its range. The species status of Crotaphopeltis barotseensis , C. degeni , and C. hotamboeia was confirmed, whereas the Afromontane species C. tornieri comprised two candidate species. Crotaphopeltis hotamboeia did not show cryptic speciation, although its phylogeographic structure corresponded with the spatiotemporal pattern of the African savanna. Our results show how the heterogeneous African environment could influence genetic partitioning of habitat specialist and generalist species at broad geographical scales.