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character is visible in illustrations of Platanista gangetica by Van Beneden &
Gervais (1868-1880:pl. XXXI, Figures 2a, 9a), and Kellogg (1926: pl. 2), and see
Figure 11A herein. (Character defined by Barnes (2006:39, character 25.)
26. Right and left halves of nuchal crest bilaterally symmetrical [0]; or left half of
nuchal crest, compared to right half of nuchal crest, curving anteriorly farther than
right half of nuchal crest [1]. The location of the nuchal crest is shown by Rommel
(1990:fig.2). The derived character state exists in Notocetus vanbenedeni (see Figure
6A herein), in Araeodelphis, cf. A. natator (see Figure 7A herein), and in Platanista
gangetica (see Van Beneden & Gervais (1868-1880:pl. XXXI, Figures. 2a, 9a; and
Figure 11A herein), and was defined by Barnes (2006:39, character 26).
27. Rostrum not remarkably elongated [0]; or rostrum elongated [1]. The rostrum is
considered to be elongated when it is 2 ½ times the anteroposterior length of the
braincase or more, the latter as measured from the antorbital notches to the occipital
condyles. The derived character state is present in Prepomatodelphis
korneuburgensis (see Barnes 2002b: Figure 1), in Zarhinocetus errabundus (see
Figure 2 herein), in Zarhachis flagellator (see Kellogg, 1924:pls. 1, 2; and Figure 9
herein), and Platanista gangetica, as illustrated by Van Beneden & Gervais (1868-
1880:pl. XXXI, Figures 1, 2, 2a, 2b, 9, 9a; and Figure 11 herein).
28. Premaxillae alone forming rostral extremity [0]; or premaxillae and maxillae both
reaching the anterior rostral extremity [1]. The plesiomorphic state exists in
Squalodontidae (Figure 4) and Waipatiidae (Figure 5). (Character was defined by
Barnes (2006:39, character 28.)
29. Premaxillae and maxillae not fused at distal end of rostrum [0]; or fused [1]. The
derived character state is present in Platanista gangetica, seen in images of that
taxon published by Van Beneden & Gervais (1868-1880: pl. XXXI, Figure1; and
Figure 11 herein). The character was defined by Barnes (2006:39, character 29), and
is modified from Fordyce (1994) and Messenger & McGuire (1998). Following
Barnes (2006:39, character 29), in this study we interpret the opposite polarity for the
character as was indicated by Geisler & Sanders (2003:99, character 10).
30. Groove on the lateral side of the rostrum approximately following the
maxilla/premaxilla suture: absent [0]; or groove present [1]. The derived character
state is exemplified by the holotype cranium of Prepomatodelphis korneuburgensis
(see Barnes, 2002b: Figures 1a-b), a referred specimen of Zarhachis flagellator (see
Kellogg, 1924:pl. 1; and Figure 9 herein), and referred specimens of Platanista
gangetica (illustrated by Van Beneden & Gervais, 1868-1880:pl. XXXI, Figure 1;
and Figure 11 herein), and was defined by Fordyce (1994:176, character 36), and by
Barnes (2006:39, character 30).
31. Lateral lamina of the pterygoid bone extending posteriorly sufficiently far to
contact the alisphenoid bone and/or the falciform process of the squamosal, thus
forming an extensive ossified lateral lamina of the pterygoid bone in the
ventromedial part of the orbit [0]; or lateral lamina of the pterygoid absent (vestigial),
not formed as an outer lamina or bony plate of the pterygoid within the orbit, and not
extending posteriorly from the palate to contact the alisphenoid and squamosal [1].
The primitive character state is present in Allodelphis pratti (see Figure 1 herein), in
Zarhinocetus errabundus (see Figs. 2 and 3 herein), in Prepomatodelphis
korneuburgensis (see Barnes, 2006: Figure 6), in Zarhachis flagellator (see Kellogg,
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