Michigan: Frogs, Toads, & Turtles

Vocabulary practice flashcards covering the identification traits, vocalizations, sizes, ploidy, and anatomical characteristics of Michigan frogs, toads, and turtles from General Biology II Lab.

Western Chorus Frog (Pseudacris triseriata)

A small Michigan frog measuring $0.75 - 1.5\,\text{inches}$ characterized by three dark stripes down its back and a white upper lip; its breeding call resembles a thumb rubbing down the teeth of a comb, and males possess a dark throat sac.

Boreal Chorus Frog

A subspecies of chorus frog found in Michigan specifically on Isle Royale.

Spring Peeper (Pseudacris crucifer)

A small frog measuring $0.75 - 1.5\,\text{inches}$ recognized by an X-shaped marking on its back and distinct toe-pads; known for a high-pitched 'peep' call as well as a low-pitched trill used to warn other males.

Wood Frog (Rana sylvatica)

A Michigan frog measuring $1.5 - 3.25\,\text{inches}$ that possesses a dark mask near its eyes, a white upper lip, two raised dorsolateral folds, and a distinctive duck-like 'quack' call.

Dorsolateral Folds

Two raised glandular ridges of skin extending down the back of certain frogs, such as the Wood Frog and Green Frog, but noticeably absent in species like the Bull Frog and Mink Frog.

Northern Leopard Frog (Lithobates pipiens)

A frog measuring $2 - 4.5\,\text{inches}$ that is green or brown with rounded spots, scarce in many parts of Michigan, and produces a low snore-call ($2 - 4\,\text{seconds}$) followed by several croaks (sounding like running a finger over a well-inflated balloon).

Gray Tree Frog (Hyla versicolor)

A tree frog measuring $1.25 - 2.5\,\text{inches}$ with dark toe pads, bright yellow inner thighs, and the ability to change color for camouflage; it is tetraploid (possessing twice the number of chromosomes) and emits a slow, musical trill lasting $1 - 3\,\text{seconds}$.

Cope’s Gray Tree Frog (Hyla chrysoscelis)

A less common Michigan tree frog measuring $1.25 - 2.5\,\text{inches}$ that possesses diploid chromosomes and emits a shorter, lower-pitched nasal trill lasting $1 - 3\,\text{seconds}$.

American Toad (Bufo americanus)

A toad measuring $2 - 4\,\text{inches}$ with dark, dry skin, prominent parotoid glands behind the eyes, and fewer bumps per dark patch; most active on warm, rainy evenings and produces a sustained trill lasting $10 - 30\,\text{seconds}$ or more.

Fowler’s Toad (Bufo woodhouse)

A toad measuring $2 - 4\,\text{inches}$ featuring a light stripe down the middle of its back, an unspotted white belly, and dark blotches containing 3 or more bumps; found along the eastern shore of Lake Michigan and gives a low, nasal bleat lasting $2 - 7\,\text{seconds}$.

Parotoid Glands

Large, raised glandular structures located behind the eyes of toads that secrete defensive toxins against predators.

Pickerel Frog (Lithobates palustris)

A Michigan frog measuring $2 - 3\,\text{inches}$ characterized by squarish dark spots arranged in two parallel rows, bright yellow inner thighs, a white belly, and toxic skin secretions; prefers cold-water streams and emits a snore-like croak.

Cricket Frog (Acris crepitans)

A small frog measuring $0.5 - 1.5\,\text{inches}$ with tiny dark bumps, long hind legs, and a dark triangle patch between the eyes; reaches its northern range limit in Michigan and makes a clicking sound resembling pebbles being struck together.

Saul Lake Bog

A notable Michigan habitat location cited as a specific site where the Cricket Frog (Acris crepitans) can be found.

Green Frog (Lithobates clamitans)

A common aquatic frog measuring $2 - 4\,\text{inches}$ with prominent dorsolateral folds, large tympanums, and yellow vocal sacs in males; makes a call resembling the twang of a plucked banjo string.

Blue Morpho (Green Frog)

A rare genetic color variation of the Green Frog (Lithobates clamitans) displaying vibrant bright blue pigmentation instead of the typical green coloration.

Mink Frog (Lithobates septentrionalis)

A frog measuring $2 - 3\,\text{inches}$ that resembles a small green frog but usually lacks dorsolateral ridges; strictly an Upper Peninsula (U.P.) species in Michigan whose call sounds like horses trotting on a cobblestone street.

Bull Frog (Lithobates catesbeianus)

The largest Michigan frog, measuring $4 - 8\,\text{inches}$, that lacks dorsolateral folds and features a tympanum larger than its eye; takes $2 - 3\,\text{years}$ to reach adulthood, with males having a yellow vocal sac and producing a deep 'br-rrum' call.

Tympanum

The external circular eardrum membrane located behind the eye in anurans, which is noticeably larger than the eye in male Bull Frogs.

Blanding's Turtle

A Michigan species of special concern recognized by its high, domed, dark, yellow-speckled carapace and bright yellow chin and throat.

Common Snapping Turtle

A common bottom-dwelling turtle in slow, shallow waters that represents the largest turtle species native to Michigan.

Eastern Musk Turtle (Sternotherus odoratus)

A small, primarily nocturnal turtle also known as the 'stinkpot', distinguished by pair stripes of yellow on the head and a habit of foraging in shallow water.

Eastern Spiny Softshell Turtle

One of North America's largest freshwater turtles, common in Michigan, characterized by a flat, flexible, rubbery shell covered with small spines, a long pointed snorkel-like snout, and the ability to breathe underwater.

Northern Map Turtle

A common Michigan turtle featuring intricate markings on its carapace that resemble topographic contour lines on a map, yellow lines along the skin, and a distinct triangular yellow spot behind each eye.

Northern Map Turtle Plastron Pattern

The intricate, swirling dark-and-light contour pattern found on the ventral shell (plastron) of juvenile Northern Map Turtles.

Painted Turtle

The most common turtle species in Michigan, recognized by its smooth, dark carapace and bright red and yellow striped markings along its neck, legs, and lower shell margins.

Red-eared Slider

A non-native turtle that closely resembles the painted turtle but features a prominent broad red stripe behind each eye and a distinct plastron; common in the pet trade, with escaped or released individuals becoming naturalized in Michigan.

Spotted Turtle

A threatened Michigan turtle of small stature (adult carapace length of $3 - 5\,\text{inches}$) featuring a smooth black to grayish-black carapace marked with small, rounded yellow spots.

Wood Turtle

A Michigan species of special concern whose name derives from the rough, sculpted, pyramidal appearance of its carapace; individual specimens can be aged by counting the concentric growth rings on their scutes.

Eastern Box Turtle

A largely terrestrial species of special concern in Michigan with a high domed shell, bright orange or yellow blotches, and a transverse hinge across its plastron that allows it to close tightly against predators.

Plastron Hinge

A flexible transverse joint across the lower shell of the Eastern Box Turtle that enables the front and back lobes to pull flush against the carapace, completely enclosing the head and limbs.

Carapace

The dorsal (upper), convex section of the shell structure in turtles, composed of bony plates covered by keratinous scutes or leathery skin.

Plastron

The flat, ventral (underside) portion of a turtle's shell structure, which may feature diagnostic markings or hinges depending on the species.