ASCAPHUS TRUEI (Tailed Frog)

COMMON NAME:  Tailed Frog   SCIENTIFIC NAME:  Ascaphus truei   STATUS:  Federal- No status;  States- No status   RANKING:  Global- Apparently secure;  Idaho- Vulnerable   FOREST PRESENT:  Boise          POSSIBLE:  Payette, Salmon-Challis, Sawtooth

DESCRIPTION:  The Tailed Frog, named from the tail-like male copulatory organ, is the only species in the family found in North America.  The frog can be up to 2 inches in length and has a yellow or greenish triangle on the snout.  Dorsal coloration is variable and ranges from yellow to almost pure black.  The skin is rough.  Key characteristic include the wide 5th toe on the hind foot and the absence of a typanic membrane.  The pupils of the eye are vertical.

LIFE HISTORY:  The Tailed Frog inhabits clear, rocky, swift, cool streams in forested habitats.  In the West this frog is found primarily in older forest of Douglas Fir, Pine, and Spruce.  In the Intermountain Region, the species is found only in Idaho, as far south as Boise, Idaho and as far east as the Salmon National Forest.

While the Tailed Frog never ventures far from water, it can venture into the forest after rains.  During dry spells, it can be found on moist stream banks or under rocks in the stream bed.  Activities that increase sedimentation and water temperature have an adverse affect on Tailed Frogs.  Low dispersal rates limit population recoveries.
 

BREEDING: Adults are most active from April to October but breeding occurs primarily in the fall.  The eggs are fertilized internally and are laid in the summer.  The eggs are unpigmented and are laid in rosary-like beads of up to 75 eggs each on the underside of rocks.
 

DIET:  Larvae feed primarily on diatoms.  Their sucker-like mouths are diagnostic.  Adult feed on a wide variety of insects and other invertebrates.
 

VOICE:  The Tailed frog has no vocal sac and apparently no voice.
 

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