Phylogeny of carnivores and features of the fetuses and placenta. (A) Systematic relationships of Carnivora, with basal dichotomy between Caniformia and Feliformia (after [25, 26]). The groups included in the comparison are marked by asterisks. (B-C) External features of the fetuses. Note the well-developed cranial region (Cr), forelimbs (Fl) and hindlimbs (Hl) with keratinized claws (Cl), and elongated tail (T). In the cranial region, note the eye (Ey) with upper (Ul) and lower (Ll) lips and pigmented retina. Hair follicles (Hf) were present in the elongated nasal region (Nr). Uc = umbilical cord. (D) Macroscopic anatomy of the term placenta in coati. Zp = zonary chorioallantoic placenta, Co/Al = noninvasive chorioallantois, Am = amnion. (E) Cytokeratin, mid-gestation. Chorioallantoic membrane (Co/Al) attached to the uterus (Ut), both with intact epithelia (arrows). Gl = uterine gland, Mv = maternal (arterial) vessel, Fv = fetal vessel.