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Summary: Placental nature of the alleged marsupial from the Cretaceous
of Madagascar
ALEXANDER O. AVERIANOV, J. DAVID ARCHIBALD, and THOMAS MARTIN
Arecently (Krause 2001) reported fragmentary mammalian
lower molar (University of Antananarivo, UA 8699) from
the Late Cretaceous (Maastrichtian) of Madagascar, was at-
tributed to Marsupialia, for which far reaching paleobio-
geographical conclusions were made. The five characters
used to identify UA 8699 as a marsupial are not exclusive to
Late Cretaceous marsupials, but are found also in some pla-
cental mammals, notably in Late Cretaceous ungulatomorph
zhelestids, known from various Upper Cretaceous strata in
Asia, Europe, and North America (Nessov et al. 1998). Iden-
tification of UA 8699 as a zhelestid placental is in keeping
with myriad other faunal similarities between Europe and
Africa/Madagascar.
Zhelestid molars, as well as UA 8699 and marsupials (Krause
2001), have the following: a postcingulid extending from the
base of the hypoconid toward the hypoconulid apex (Fig. 1C)
(although its prominence varies across the diverse zhelestids), a
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