Boyer diss 2009 1046..

Premaxilla and premaxillary dentition.— The anterior part of the right premaxilla
is preserved (Fig. 3.2). The nasal, maxillary, and symphyseal premaxillary sutures are
visible. The nasal suture is straight and simple (Figs. 3.1, 2: 1). The right maxillary
suture is observable just posterior to I 2 (Fig. 3.2: 2). The suture is not convoluted and
runs dorsoventrally before starting to curve posteriorly. A strip of bone exists along this
sutural edge, which obtains an anteroposterior width of up to about 2 mm and appears to
have received the maxilla on its lateral side. A higher magnification view of this surface
reveals anteroposteriorly directed grooves and ridges, marking the early stages of what
would likely have become pronounced “inter-locking” of bones along the
maxillary/premaxillary suture in an older individual (Fig. 3.2B: inset). Whether the
incisive foramen is contained completely within the premaxilla or at the juncture with the
maxilla cannot be determined because of some breakage in this region (Fig. 3.2, 5). Even
so, the symphyseal surface for the right premaxilla is present (Fig. 3.2: 3), as well as
some surface for palatal contact with the maxilla (Fig. 3.2: 2). The premaxilla has alveoli
for just two teeth, interpreted as I 1 and I 2 , the latter of which is preserved in place (Fig.
3.2). The I 1 is not preserved; however, this tooth is known for the species (see below).
The right I 2 is a simple, caniniform tooth. It has a paracone, with a distinct,
postprotocrista extending between the apex of the cusp and the base of the crown on the
distal side of the tooth. The crown is slightly compressed buccolingually relative to its
mesiodistal dimensions. I 2 measures 4.12 mm in mesiodistal length and 2.95 mm in
mediolateral width.
Lacrimal.— Due to crushing, the lacrimals have been almost completely
destroyed. The rostrum has been shifted posteriorly and the anterolateral margins of the
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