Population genetic structure and connectivity in three montane freshwater invertebrate species (Ephemeroptera, Plecoptera, Amphipoda) with differing life cycles and dispersal capabilities

• Published in: Freshwater biology 2022-03, Vol.67 (3), p.461-472
• Main Authors: Schröder, Oskar, Schneider, Julio V., Schell, Tilman, Seifert, Linda, Pauls, Steffen U.
• Format: Article
• Language: English
• Subjects: Aquatic crustaceans; Aquatic insects; Aquatic invertebrates; Aquatic organisms; Aquatic populations; Community structure; Connectivity; Cytochrome; Cytochrome oxidase I; Cytochromes; Dispersal; Dispersion; DNA barcoding; Europe; Freshwater; Freshwater invertebrates; Gene flow; Genetic markers; Genetic structure; Inland water environment; Invertebrates; Life cycles; Microsatellites; Mitochondria; mountain streams; Mountains; National parks; Population; Population genetics; Population structure; Population studies; Rivers; Species; Streams; Topology
• ISSN: 0046-5070; 1365-2427
• DOI: 10.1111/fwb.13854

Dispersal abilities and the resulting levels of connectivity between streams influence population structure in aquatic organisms. We investigated how different dispersal and life‐history traits affect gene flow and population structure in three aquatic invertebrate species in a central European mountain range. We used microsatellite markers and mitochondrial cytochrome oxidase I barcode data to assess small‐scale population structure and connectivity of the mayfly Baetis alpinus, the stonefly Brachyptera seticornis, and the amphipod Gammarus fossarum in seven streams within Bavarian Forest National Park, Germany. Significant population structure within the study area was detected in B. alpinus and G. fossarum, whereas B. seticornis had signatures of panmixia. In G. fossarum, that structure corresponded to stream topography, while in B. alpinus it did not. The Bavarian Forest range appears to be a contact zone for different mitochondrial lineages of B. alpinus and G. fossarum. Limited geneflow between sample sites in B. alpinus can be explained by the species’ short adult lifespans, which restricts dispersal between sites. Since imagines are able to disperse via adult flight population structure is, however, decoupled from stream topology. Longer‐lived B. seticornis is better able to maintain geneflow between sample sites. In flightless G. fossarum, population structure corresponding to stream topology can be explained by limited dispersal capabilities between streams. Dispersal ability alone is insufficient to predict or explain patterns of gene flow and connectivity for individual species, and should be examined together with life‐history traits when assessing population and community structure.