Fairy shrimp (Crustacea: Anostraca) are
specialist inhabitants of temporary aquatic habitats. In
many parts of the world and particularly in Western
Europe, however, populations are declining while the
development of adequate conservation strategies is
impeded by a poor knowledge of the genetic structure
and taxonomic status of remaining lineages. We
reconstructed a phylogeography of the species Chirocephalus
diaphanus Pre´vost, 1803 using partial
sequences of the mitochondrial COI gene and discuss
the importance of different Pleistocene refugia to
explain current diversity patterns. In addition to 20 C.
diaphanus populations, we also included populations
of six presumably closely related chirocephalids to
evaluate their taxonomic status. Based on molecular
data, the Eastern European subspecies C. diaphanus
romanicus deserves species status while the species
status of two Italian chirocephalids, C. salinus and C.
ruffoi is questionable. Results indicate European C.
diaphanus lineages diverged well before the last
glacial maximum and survived the Pleistocene glaciations
in multiple (sub)refugia along the Iberian,
Italian, and Balkan peninsula. Northern Europe was
subsequently recolonized from Southern France,
resulting in high levels of cryptic diversity around
glacial refugia but also in more widespread haplotypes
in mainland Europe.