subnarial fossa is present on the lateral surface of the premaxilla. As in other oviraptorids
(Clark et al., 2002; L俟 et al., 2004; Osm佼lska et al., 2004)(Figs. 1B; 2), the frontal is an鄄
teroposteriorly short, whereas the parietal is long (Fig. 1A). There is a shallow longitudinal
groove rather than a sagittal crest along the midline of the fused parietals. The descending
process of the pneumatic lacrimal has strongly convex anterior and lateral surfaces (Figs. 1A;
2). The suborbital ramus of the jugal is slender and slightly flattened mediolaterally. As in Citi鄄
pati (Clark et al., 2002), it is perpendicular to the postorbital process, which is strongly up鄄
turned (Fig. 1A). The quadrate is very robust, and terminates ventrally in two large condyles
separated by an oblique groove (Fig. 1A). The occiput faces posterodorsally. Both the nuchal
transverse crest and the supraoccipital crest are weak. The paroccipital process is short and ven鄄
trally pendant. The palate exhibits several features intermediate in condition between basal ovi鄄
raptorosaurs and other oviraptorids. The pterygoid has an anteroposteriorly long palatal ramus in
comparison to other oviraptorids (Osm佼lska et al., 2004), amounting to about one鄄third of the
basal skull length. There is a longitudinal trough along the dorsal surface of the palatal ramus,
the lateral border of which is formed by the pterygoid鄄ectopterygoid bar (Fig. 1B). Other ovi鄄
raptorids lack this feature, although they possess a trough along the ventral surface of the palatal
ramus (Osm佼lska et al., 2004). A deep fossa is present on the medial wall of the dorsal trough
of Banji, a feature unknown in any other oviraptorosaur (Osm佼lska et al., 2004) (Fig. 1B).
The long ectopterygoid lies anterolateral to the pterygoid, a condition intermediate between typi鄄
cal non鄄avian theropods and other oviraptorids (Figs. 1B; 2). The maxillary process of the ec鄄
topterygoid extends anteriorly and lacks a strong dorsal extension as in other oviraptorids
(Osm佼lska et al., 2004). This feature is consistent with the position of the vomer, which lies at
about the same level as most of the other palatal elements.
The mandible is massive, with an extremely anteriorly located mandibular fenestra, the an鄄
terior border of which even extends beyond the anteroventral corner of the dentary when the ven鄄
tral edge of this bone is horizontally oriented (Figs. 1, 2). The symphyseal portion of the den鄄
tary is downturned in lateral view and U鄄shaped in ventral view. The dentary has a highly con鄄
vex dorsal margin, in contrast to the gentler convexity seen in more basal oviraptorosaurs such
as Incisivosaurus (Xu et al., 2002) and in therizinosaurs (Clark et al., 2004). In most other
oviraptorids, the dentary has a concave anterodorsal margin in lateral view (Osm佼lska et al.,
2004). A few sharp ridges and grooves are present on the posteriormost part of the dorsal mar鄄
gin of the dentary, and posterior to the coronoid process are several small but distinct tubercles
along the lateral shelf at the dorsal margin of the surangular (Figs. 1B; 2) These features have
not been reported in any other oviraptorosaur. Immediately posterior to the mandibular fenestra
is a prominent, well defined fossa, which contains several large foramina. Above the fossa is a
distinct groove along the dorsal margin of the surangular (Fig. 1A). A similar groove is also
known in Incisivosaurus (IVPP V 13326) and some maniraptorans, but in oviraptorids the dor鄄
sal edge of the surangular in this region is relatively narrow and rounded.
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