TY - JOUR
T1 - Phylogeny, species delimitation and ecological and morphological diversity of Characithecium (Monogenoidea: Dactylogyridae)
AU - Wendt, Emília W.
AU - Malabarba, Luiz R.
AU - Braga, Mariana P.
AU - Boeger, Walter A.
AU - Landis, Michael
AU - Carvalho, Tiago P.
N1 - Funding Information:
We acknowledge all the financial institutions (listed below) that contributed to this study being carried out. We thank Dr Lia Lunaschi, the curator of the helminthological collection at Colección de Invertebrados del Museo de La Plata, for providing photos of the holotypes of the several Characithecium species. We thank Dr Marcelo Knoff, the curator of the helminthological collection of the Instituto Oswaldo Cruz, Rio de Janeiro, Brazil (CHIOC), for providing Characithecium vouchers in this important zoological collection. We thank the curators and personnel of the following ichthyological collections for providing material: F. Langeani (DZSJRP); C. Oliveira (LBP); C. Lucena (MCP); F. Jerep and O. Shibatta (MZUEL) and F. Carvalho (ZUFMS). We also thank V. Tkach, J. Weckstein and L. Bachmann for help and comments provided on the molecular work on parasites, host–parasite relationships and for many other discussions. We thank A. Ferrari, B. Sidlaukas and R. Vianna for comments on an early version of this manuscript. This study was funded by CAPES with a doctorate scholarship and was partially funded by Systematics Research Fund 2017/18, both granted to E. W. W. Field trips for collecting hosts were partially funded by a CNPq Universal grant (401204/2016-2) to L. R. M. T. P. C., during most of the duration of this project, was funded by CAPES with a PNPD postdoctoral fellowship.
Publisher Copyright:
Copyright © The Author(s), 2022. Published by Cambridge University Press.
PY - 2022/4/3
Y1 - 2022/4/3
N2 - Characithecium (Monogenoidea, Dactylogyridae) is a genus containing nine species that live on the gills of a characid clade containing genera Astyanax, Andromakhe, Psalidodon and Oligosarcus (Characiformes, Characidae) in South and Central America. Earlier studies suggest a tight coevolutionary history between these parasites and their hosts mainly due to the phylogenetic proximity between these genera of fish. Hence, this study explores phylogenetic relationships, species limits and extrinsic factors (geography and ecology) explaining parasite prevalence. To understand the evolutionary history of the genus, we constructed a time-calibrated phylogenetic hypothesis, which includes eight of the nine known species of Characithecium sampled from a broad spectrum of host species. The phylogeny supports the monophyly of Characithecium, with its most recent common ancestor dating from the Miocene. Using generalized mixed-yule coalescent and Bayesian Poisson tree process methods, species delimitation analyses suggested fewer species than the proposed delimitation based on morphology alone, recovering four and six entities, respectively. The results indicate that species of Characithecium have wider geographical and host distribution and higher prevalence on Oligosarcus species compared to Astyanax and Psalidodon. Correlation between parasite prevalence and biotic and abiotic traits, based on generalized linear models, indicates that the frequency of occurrence of different species of Characithecium is associated with distinct factors, such as host genus, high altitudes, rivers and streams, and different ecoregions. Our results suggest that species of Characithecium are highly opportunistic, exploring resources in different manner as our data reveal the ability of these parasites to explore a diverse environment of variable biotic (e.g. hosts) and abiotic features.
AB - Characithecium (Monogenoidea, Dactylogyridae) is a genus containing nine species that live on the gills of a characid clade containing genera Astyanax, Andromakhe, Psalidodon and Oligosarcus (Characiformes, Characidae) in South and Central America. Earlier studies suggest a tight coevolutionary history between these parasites and their hosts mainly due to the phylogenetic proximity between these genera of fish. Hence, this study explores phylogenetic relationships, species limits and extrinsic factors (geography and ecology) explaining parasite prevalence. To understand the evolutionary history of the genus, we constructed a time-calibrated phylogenetic hypothesis, which includes eight of the nine known species of Characithecium sampled from a broad spectrum of host species. The phylogeny supports the monophyly of Characithecium, with its most recent common ancestor dating from the Miocene. Using generalized mixed-yule coalescent and Bayesian Poisson tree process methods, species delimitation analyses suggested fewer species than the proposed delimitation based on morphology alone, recovering four and six entities, respectively. The results indicate that species of Characithecium have wider geographical and host distribution and higher prevalence on Oligosarcus species compared to Astyanax and Psalidodon. Correlation between parasite prevalence and biotic and abiotic traits, based on generalized linear models, indicates that the frequency of occurrence of different species of Characithecium is associated with distinct factors, such as host genus, high altitudes, rivers and streams, and different ecoregions. Our results suggest that species of Characithecium are highly opportunistic, exploring resources in different manner as our data reveal the ability of these parasites to explore a diverse environment of variable biotic (e.g. hosts) and abiotic features.
KW - Divergence time estimates
KW - host-parasite associations
KW - molecular phylogeny
KW - morphological
KW - taxonomy
UR - http://www.scopus.com/inward/record.url?scp=85125878601&partnerID=8YFLogxK
U2 - 10.1017/S0031182022000221
DO - 10.1017/S0031182022000221
M3 - Article
C2 - 35236513
AN - SCOPUS:85125878601
SN - 0031-1820
VL - 149
SP - 700
EP - 716
JO - Parasitology
JF - Parasitology
IS - 5
ER -