Flask-shaped microfossils are reported from bracts of a moss in Eocene
-Oligocene amber from the northern Dominican Republic. These microfoss
ils are identical with the thecae of certain living moss-dwelling roti
fers in the genus Habrotrocha (Bdelloidea), which have previously been
reported as fossils only from Holocene peat. What may be an egg and a
rotifer body fossil are associated with these thecae and further supp
ort the identification of these fossils with Habrotrocha; the fossils
are almost identical to extant H. angusticollis. The parthenogenetic b
delloid rotifers have a longer evolutionary history than was previousl
y thought; habrotrochid rotifers seem to have persisted for 35 million
years with very little change in morphology or ecological role.