Figure 2.

Three of many feasible options for Widanelfarasia's systematic position given differing assumptions of placental interrelationships. Possible lower dental synapomorphies are given at selected nodes. (A) The option preferred (but still weakly supported) by this study, under the assumption that tenrecids and chrysochlorids are sister taxa, Solenodon is unlikely to be the extant sister taxon of a tenrecid–chrysochlorid clade, and the extant sister taxon of the tenrecid–chrysochlorid clade is currently unclear—molecular data (e.g., ref. 12) suggest that it is some segment of “Afrotheria.” Nodes: 1, loss of P₁, enlarged I₂ with basal cusp, possibly deep hypoflexids and a semimolariform P₄; 2, marked reduction of molar talonids, possibly a reduction of the lower canine. This option gains additional support from biogeographic considerations. (B) Possible relationships under the assumption that living and extinct zalambdodont placentals are monophyletic. Nodes: 1, semimolariform P₄; 2, loss of P₁, increased depth of hypoflexids; 3, marked reduction of molar talonids; 4, relatively large I₂. (C) Widanelfarasia mapped onto a cladogram of Lipotyphla as suggested (in part) by Butler (33). Lower dental features considered in this paper are quite labile given this scenario. Nodes: 1, loss of P₁, enlarged I₂ with basal cusp, deep hypoflexids; 2, marked reduction of molar talonids, possibly a reduction of the lower canine; 3, increased dilambdodonty.