Analysis of Characters The characters used in the systematic study of the frogs in this group are those usually employed in anuran systematics.
"A Review of the Frogs of the Hyla bistincta Group"
William E. Duellman
1-6. February 21. 1967. Additional studies of chromosomes of anuran amphibians.
"Middle American Frogs of the Hyla microcephala Group"
William E. Duellman M. J. Fouquette