Nathan J. Dorn

A mysterious parthenogenetic cambarid crayfish (the Marmorkrebs)
has been spreading across the globe for the past decade.
We compare this crayfish directly to two other cambarids, Procambarus
fallax and P. alleni, that have been suggested to be
related or even identical to the Marmorkrebs. Using external
morphology and sequences of two mitochondrial genes we
show clear correspondences between Marmorkrebs and P. fallax,
a species found natively throughout peninsular Florida,
USA. Based on these congruent results we suggest that the Marmorkrebs
is the parthenogenetic form of P. fallax. This finding
has potential evolutionary and ecological implications at several
levels. The Marmorkrebs might be a type of geographical parthenogenesis,
but a natural population in the wild is so far unknown.
Furthermore, challenges arise in regard to the respective
species status of the Marmorkrebs. Taxonomically we suggest
that the Marmorkrebs is treated as ‘parthenogenetic form’ of P.
fallax. Last but not least, the identity of this animal and its ecology
has an impact for considering potential spread and effects of
this species across the globe.