However... Amphibiaweb shows that both Hyla chrysoscelis http://amphibiaweb.org/cgi/amphib_query?special=maps&genus=Hyla&species=chrysoscelis&photos=yes
and Hyla versicolor (Gray Treefrog) http://www.amphibiaweb.org/cgi/amphib_query?special=maps&genus=Hyla&species=versicolor&photos=yes
may occur in this area. As stated on Herp.net, http://www.herpnet.net/Iowa-Herpetology/index.php?option=com_content&task=view&id=80&Itemid=26
The Cope's gray treefrog is identical in appearance to the eastern gray treefrog. There is (as of now, anyway) no reliable way to distinguish these frogs based on appearance on a consistent basis. The pattern on the backs of each species is unreliable as they both may or may not have a pattern; observations based on positive identification indicates that one has a pattern more often than the other. The only steadfast differences between these two species is the number of chromosomes (the Cope's gray treefrog is a diploid, the eastern gray treefrog is a tetraploid), and that the Cope's has smaller red blood cells than the eastern gray treefrog, and differences in the advertisement calls of the males (see habits).'
Their calls differ slightly - you can hear them here --- http://wwknapp.home.mindspring.com/docs/gray.tfrogs.html
Comments (5)