Figure 7. Postcranial material referred to Crocodylus anthro- pophagus. A, KNM DK I B, left scapula, lateral view; B, NHM R.5894, ?nuchal osteoderm; C, KNM DK I B OLD 62 54, right humerus, ventral view; D, KNM FLKNI, right femur, ventral view. Scale = 5 cm. doi:10.1371/journal.pone.0009333.g007 shaped object with a dorsal concavity flooring the neural canal and prominent diapophyses (Fig. 3C). The axis centrum bears a robust hypapophysis behind the odontoid process, which in the holotype appears to have largely fused with the axial centrum (Fig. 3D), even though the neural arch had popped off along its sutural surface. Vertebrae are procoelous. The scapula has a relatively slender dorsal blade, a narrow deltoid crest, and mediolaterally wide body (Fig. 7A). The deltopectoral crest of the humerus was concave proximally (Figs. 3E, 7A). The lateral surface of the ilium is not visible on the holotype, but in posterior view it reveals a wasp-waisted posterior blade (Fig. 3G). The femur is sigmoid in shape and had shallow depressions for the caudofemoralis musculature on its ventral surface anterior and posterior to the fourth trochanter (Fig. 7D). Most osteoderms (presumably from the dorsal shield) are square in dorsal view and, in most cases, bear a robust dorsal keel (Fig. 3B); at least one (Fig. 7B) is oval in dorsal view, suggesting it is from the nuchal shield. Methods Crocodylus anthropophagus was added to a matrix of 98 morpho- logical characters and 34 ingroup taxa (Appendix S1). A maximum parsimony analysis was conducted using TNT 1.1 [44]. 100 random-seed heuristic searches were performed. Borealosuchus sternbergii, Pristichampsus vorax, and Leidyosuchus canadensis were used as sequential outgroups. Optimal trees were exported to PAUP 4.10b [45] to construct Adams consensus trees. Results The heuristic searches recovered 426 equally optimal trees (length = 225, CI excluding uninformative characters = 0.493, RI = 0.717). Strict and Adams consensus trees of these results (Fig. 8) are broadly congruent with previous morphological analyses [23,27,46]. Mecistops is the closest relative of Crocodylus. Groups of Afro-Malagasy and Australasian forms – osteolaemines and mekosuchines, respectively – form subclades within Croco- dylinae. If the relationships among outgroup taxa are not constrained to reflect more inclusive analyses of Crocodylia (i.e. forcing Leidyosuchus to be closest to Crocodyloidea and Borealosuchus Extinct Horned Crocodile sternbergii as the basalmost outgroup), Pristichampsus is closer to Crocodyloidea and trees are one step shorter. Character sampling in this analysis was focused on variation among crocodyloids. Most of the characters relevant to relationships among non-crocodyloid lineages were not included. Crocodylus is less resolved than in previous morphological analyses. This reflects incompleteness in two extinct species - Crocodylus anthropophagus and C. palaeindicus. Crocodylus anthropophagus assumes seven positions in the optimal trees – closely related to C. niloticus, C. rhombifer, C. palaeindicus, C. siamensis, the Neotropical clade, the Afro-Neotropical group, or the Indopacific group. Adams consensus trees (Fig. 8) restore the close relationship between the Neotropical species and C. niloticus supported by morphological [23] and molecular [24,25] evidence. Placements of C. anthropophagus within the Indopacific or Neotropical clades (other than as a close relative to C. rhombifer or C. siamensis) increase tree length by only one step. None of the most parsimonious placements has bootstrap support exceeding 50%. Hence, although the data analyzed here support placement of C. anthropophagus close to (if not within) Crocodylus, we are unable to pinpoint its relationships more precisely. Discussion Phylogenetic Relationships A close relationship between Crocodylus anthropophagus and extant Crocodylus is supported by several unambiguous character states. In all crocodylians, the pharynx pneumatizes the braincase through three small openings (the Eustachian foramina) between the basioccipital and basisphenoid on the occipital plate [47,48]. Osteolaemines (including Rimasuchus) and Mecistops share the ancestral condition in which the lateral foramina are located dorsal to the median foramen. In Crocodylus the lateral foramina are located ventrally and almost in line with the median foramen [23]. This coincides with a decrease in the dorsoventral depth of the pterygoid ventral to the median Eustachian foramen, which in turn limits the exposure of the basisphenoid ventral to the basioccipital on the posteroventral surface of the skull. This is the condition found in C. anthropophagus (Fig. 5C). The medial wall of the caviconchal recess – a large pneumatic feature in the maxilla dorsomedial to the toothrow – is perforated with a linear array of blind pits in C. anthropophagus (Fig. 4H). This is a derived feature found only in Crocodylus [23,49]. The condition in Rimasuchus is unknown, but they are absent from Osteolaemus, ‘‘Crocodylus’’ pigotti, and Voay [27] (pers. obs.). An isolated ilium associated with the C. anthropophagus holotype reveals a deeply concave dorsal and ventral margin to the posterior blade, resulting in the ‘‘wasp-waisted’’ condition found in Crocodylus but absent from other crocodyloids (Fig. 3G) [23]. The ilium of R. lloydi is unknown, but the posterior blade of Voay lacks substantial notching [27]. Derived states typically found in osteolaemines are absent from C. anthropophagus. The quadrate-squamosal suture follows the sulcus between the paroccipital process and anterior quadrate ramus, and the squamosal does not lap over the dorsal surface of the ramus. The surface of the fused pterygoids anterior to the internal choana is elevated, but the elevation apparently does not surround the chaoanal aperture as it does in osteolaemines, and there is no choanal neck. Trees supporting a close relationship between C. anthropophagus and R. lloydi are minimally seven steps longer than optimal. Cranial ornamentation features that diagnose C. anthropophagus are elaborations of features found among most derived crocody- loids. The orbital rim is upturned in all extant Crocodylus, but PLoS ONE | www.plosone.org 8 February 2010 | Volume 5 | Issue 2 | e9333