BI 461 Herpetology - Frog Identification

Tympanum

Dorsolateral Fold

Bufonidae

The Toads (two species)

American Toad (Anaxyrus americanus) - Bufonidae

● Stout body

● Warty skin

● 1-2 warts per spot

● Spotted chest and belly

● Call: Long musical trill

Fowler’s Toad (Anaxyrus fowleri) - Bufonidae

● Similar to American Toad

● Multiple warts per spot

● Very few spots on belly

● Call: Low-pitched nasal waaa

Hylidae

Tree Frog and Allies (six species)

Blanchard’s Cricket Frog (Acris blanchardi) - Hylidae

● Smallest amphibian

● Warty skin

● Variable coloring

● Often a triangle between eyes

● Call: Metallic clicking increasing in tem

Eastern Gray Tree Frog (Hyla versicolor) - Hylidae

● Able to change color

● Large adhesive toe pads

● Dark irregular blotches on black

● Call: Short musical trill

Cope’s Gray Tree Frog (Hyla chrysoscelis) - Hylidae

● Identical to H. versicolor

● Call: Fast harsh trill

Midland Chorus Frog (Pseudacris triseriata) - Hylidae

● White stripe on upper lip

● Dark stripe from nostril to groin

● Three dark stripes on back

● Call: Cree-eee-eee-eek

Boreal Chorus Frog (Pseudacris maculata) - Hylidae

● Very similar to P. triseriata

● Shorter hind legs

● Three back stripes broken into spots (sometimes)

● Call: Cree-eee-eee-eek (but slower)

Spring Peeper (Pseudacris crucifer) - Hylidae

● Brown, tan, or grey

● Dark stripes on back form an “X”

● Can lighten or darken color

● Call: Peep! Peep!

Ranidae

True Frogs (six species)

American Bull Frog (Lithobates catesbeiana) - Ranidae

● Largest frog in North America

● No dorsolateral fold

● May have dark bands on back legs

● Call: Brr-rr-rrum

Green Frog (Lithobates clamitans) - Ranidae

● Green or olive

● Dorsolateral fold

● Green or yellow upper lip

● Call: Loose banjo string

Mink Frog (Lithobates septentrionalis) - Ranidae

● Produce musky odor

● Green upper lip

● Moderately to heavily marked with dark spots

● Dorsolateral folds usually poorly developed or absent

● Call: tok tok tok

Wood Frog (Lithobates sylvatica) - Ranidae

● Brown with dark mask

● White line along upper lip

● Prominent dorsolateral fold

● May have dark spots along dorsolateral fold

● Call: Clucking

Northern Leopard Frog (Lithobates pipiens) - Ranidae

● Light colored dorsolateral folds

● Rounded spots

● White line along upper lip

● Call: Rumbling snore

Pickerel Frog (Lithobates palustris) - Ranidae

● Square spots outlined in black

● Light line along upper lip

● Gold on groin and underside of legs

● Call: Weak snore-like croak