Lack of host specialization despite selective host use in brood parasitic cuckoo catfish

0577870 - ÚBO 2024 RIV US eng J - Journal Article
Reichard, Martin - Koblmüller, S. - Blažek, Radim - Zimmermann, Holger - Katongo, C. - Bryjová, Anna - Bryja, Josef
Lack of host specialization despite selective host use in brood parasitic cuckoo catfish.
Molecular Ecology. Roč. 32, č. 22 (2023), s. 6070-6082. ISSN 0962-1083. E-ISSN 1365-294X
R&D Projects: GA ČR(CZ) GX21-00788X
Institutional support: RVO:68081766
Keywords : brood parasitism * fish * host specialisation * host-parasite relationship * interspecific interactions * social evolution
OECD category: Zoology
Impact factor: 4.9, year: 2022
Method of publishing: Open access
https://onlinelibrary.wiley.com/doi/10.1111/mec.17173

Host-parasite dynamics involve coevolutionary arms races, which may lead to host specialization and ensuing diversification. Our general understanding of the evolution of host specialization in brood parasites is compromised by a restricted focus on bird and insect lineages. The cuckoo catfish (Synodontis multipunctatus) is an obligate parasite of parental care of mouthbrooding cichlids in Lake Tanganyika. Given the ecological and taxonomic diversity of mouthbrooding cichlids in the lake, we hypothesized the existence of sympatric host-specific lineages in the cuckoo catfish. In a sample of 779 broods from 20 cichlid species, we found four species parasitized by cuckoo catfish (with prevalence of parasitism of 2%-18%). All parasitized cichlids were from the tribe Tropheini, maternal mouthbrooders that spawn over a substrate (rather than in open water). Phylogenetic analysis based on genomic (ddRAD sequencing) and mitochondrial (Dloop) data from cuckoo catfish embryos showed an absence of host-specific lineages. This was corroborated by analyses of genetic structure and co-ancestry matrix. Within host species, parasitism was not associated with any individual characteristic we recorded (parent size, water depth), but was costly as parasitized parents carried smaller clutches of their own offspring. We conclude that the cuckoo catfish is an intermediate generalist and discuss costs, benefits and constraints of host specialization in this species and brood parasites in general.
Permanent Link: https://hdl.handle.net/11104/0346967


Research data: Dryad