On the structure of the aortic valves in snakes (Reptilia: Serpentes)

Aortic valve morphology was examined in 32 species of snakes representing 28 genera and 11 families and a diversity of habitat preferences. The results largely agree with previous studies but include some previously undescribed features, such as the cranial displacement of the cusps in the left aorta in some species and the structure of the opposing cusps of the interaortic foramen. Few features of the aortic valves are uniform among species. The pattern of morphological variation does not correlate with simple habitat preference (e.g., terrestrial, arboreal); however, some of the variation, particularly in the valves themselves, correlates with taxonomic relationships. We suggest that the presence of an interaortic foramen, with its associated valve, could result in an interaortic shunt of blood that potentially alters hemodynamics and flow patterns in the systemic circulation of snakes. © 1993 Wiley-Liss, Inc.