Figure 1 in Evolutionary morphology of the coelurosaurian arctometatarsus: descriptive, morphometric and phylogenetic approaches

Figure 1. Phylogenetic hypotheses of coelurosaurian relationships: (A) after Clark et al. (2002), and (B) after Holtz (2000). The designation 'Arcto.' signifies the occurrence of an arctometatarsus, with a proximal splint of metatarsal III (MT III) that is unfused to MT II and MT IV and a triangular distal cross section (Holtz, 1995). The designation '(Arcto.)' indicates a variant on this morphology, with proximal fusion of MT II-IV (the caenagnathid Elmisaurus), gradual tapering of MT III proximally rather than a rectangular splint (the caenagnathid Chirostenotes), or the loss of the proximal portion of MT III (Asian alvarezsaurids such as Mononykus and Parvicursor). (B) shows the arctometatarsus as a synapomorphy of an ornithomosaur- tyrannosaurid clade. *Signifies alternate placements of Troodontidae.