illustrated guide to the identification of cladoceran subfossils from lake sediments in northeastern North America: part 1—the Daphniidae, Leptodoridae, Bosminidae, Polyphemidae, Holopedidae, Sididae, and Macrothricidae

Cladocera identifications based on subfossil remains differ considerably from identifications based on whole animals, yet despite this very few subfossil Cladocera identification guides exist. In particular, taxa belonging to the families Daphniidae, Leptodoridae, Polyphemidae, Holopedidae, Sididae, and Macrothricidae tend to preserve poorly, with only a few, small body parts available for identification within the sediments. Since many of these taxa are important environmental indicators in lakes, subfossil identification guides that enable them to be recognized based on only a few body parts are critical for paleolimnological investigations utilizing Cladocera. In this illustrated identification guide, we provide detailed descriptions of subfossil remains commonly recovered for 14 species belonging to the families Daphniidae, Leptodoridae, Polyphemidae, Holopedidae, Sididae, Macrothricidae, and Bosminidae for lakes in eastern Canada and northeastern USA, where several recent subfossil Cladocera-based investigations of environmental change have been focused. It is our hope that this taxonomic guide will improve consistency in subfossil Cladocera taxonomy among laboratories, and help to stimulate additional research in this ecologically significant region. The diverse taxa belonging to the family Chydoridae are considered separately.