Evolution

Elopomorpha comprise a phylogenetically unique species that form a bridge between the basal and higher teleosts. The species within the orders Elopiformes, Albuliformes, Anguilliformes and Saccopharyngiformes have undergone considerable adaptive radiation, making members of the Elopomorpha well suited for evolutionary studies. The Anguilliformes are the most diverse order in the Elopomorpha. Its members are classified into three suborders: the Muraenoidei, Congroidei, and Anguilloidei and are found in a wide range of habitats from equatorial to polar regions, mountain streams to the ocean floor, and seawater to freshwater environments. The feeding habits are similarly diverse with Anguilliformes occupying an important position for the examination of phylogenetic evolution of the digestive system. Hideo Akiyoshi, Histological and Scanning Electron Microscopic Examination of the Digestive Tract in Whitespotted Conger, Conger Myriaster (Anguilliformes)