Three rare geoemydid turtles described from Chinese trade specimens in the early 1990s,
Ocadia glyphistoma,
O. philippeni, and
Sacalia pseudocellata, are suspected to be hybrids because they are known only from their original descriptions and because they have morphologies
intermediate between other, better-known species. We cloned the alleles of a bi-parentally inherited nuclear intron from samples
of these three species. The two aligned parental alleles of
O. glyphistoma,
O. philippeni, and
S. pseudocellata have 5–11.5 times more heterozygous positions than do 13 other geoemydid species. Phylogenetic analysis shows that the two
alleles from each turtle are strongly paraphyletic, but correctly match sequences of other species that were hypothesized
from morphology to be their parental species. We conclude that these rare turtles represent recent hybrids rather than valid
species. Specifically, “
O. glyphistoma” is a hybrid of
Mauremys sinensis and
M.␣cf.
annamensis, “
O.␣philippeni” is a hybrid of
M. sinensis and
Cuora trifasciata, and “
S. pseudocellata” is a hybrid of
C. trifasciata and
S. quadriocellata. Conservation resources are better directed toward finding and protecting populations of other rare Southeast Asian turtles
that do represent distinct evolutionary lineages.
Keywords Geoemydidae - Hybridization - Conservation - Nuclear DNA