WHAT IS A SUIFORME (ARTIODACTYLA) - CONTRIBUTION OF CRANIOSKELETAL AND MITOCHONDRIAL-DNA DATA

Suiformes (Artiodactyla) traditionally includes three families: Suidae , Tayassuidae, and Hippopotamidae but the monophyly of this suborder h as recently been questioned from molecular data. A maximum parsimony a nalysis of molecular, morphological, and combined data was performed o n the same set of taxa including representatives of the three Artiodac tyla suborders (Suiformes, Ruminantia, and Tylopoda) and Perissodactyl a as outgroup. Mitochondrial (cytochrome b and 12S rRNA) sequence comp arisons support the monophyly of Suina (Suidae and Tayassuidae) and An codonta (Hippopotamidae) but not the monophyly of Suiformes. Inversely , our preliminary morphological analysis supports the monophyly of Sui formes whereas relationships among the three families are not resolved . The combined data set does not resolve the relationships between Sui na, Ancodonta, and Ruminantia. These results are discussed in relation to morphological characters and paleontological data. Some improvemen ts are suggested to clarify the morphological definition of Suiformes and relationships among them. (C) 1998 Academic Press.