Azuay Stubfoot Toad

Atelopus bomolochos

HOLOTYPE.—CAS 93910, female, from Ecuador, Azuay Province, Sevilla de Oro, approximately 2800 meters. Collected January 9, 1958, by G. Frymire, A. Embree, and S. Strobel.

DIAGNOSIS.—A member of the ignescens group, most similar to ignescens, from which it is distinguished by the light dorsal coloration often marked with irregular dark spots; ratio head length/standard distance ×100 usually greater than 33; warts and pustules absent on upper arm, crus, and ankle, but present on sides from tympanic area to groin, usually absent on dorsal and ventral surfaces of body; first digit on forefoot distinct, almost totally free of webbing.

DESCRIPTION.—Snout from above gently rounded or with blunt point; distinct angle above nostril; snout, canthus, and upper eyelid fleshy and raised, with flattened, glandular, fleshy ridge from posterior corner of eye to end of head. Dorsum of head between fleshy areas slightly concave or flat, smooth. Eyes protrude laterally, dorsal area of eye in same plane as rest of head. Snout from side extends short distance beyond level of lower jaw and upper lip, nostril lateral, occasionally directed slightly backward, on raised, rounded area. Loreal region distinctly concave; fleshy area over eye fused with upper eyelid; upper lip slightly fleshy. Temporal area studded with glandular prominences, rounded in males, covered with spiny points in females. Middorsum of body completely free of warts, glands, or pustules; usually quite smooth. Dorsolateral area of neck with heavy, glandular fold, shelflike in appearance, extending back from dorsolateral temporal fold, sides wrinkled and folded, covered by small white or yellow pustules from tympanic area to groin, and on upper arms and thighs; pustules may be single and evenly scattered or bunched together. Chin, chest, and belly with wrinkles and folds, most prominent on chest. No pustules or spicules on ventral surfaces, although occasional individuals show very tiny spiculations on chest.

Forelimb short and heavy; upper humeral region with spicules, but lower humeral region and forearm free of spicules, smooth or coarsely wrinkled. When forelimb is stretched along body, fingertips do not extend beyond posterior margin of thigh. Flesh of forefoot swollen; all digits free, with fleshy webbing only at base. Sole of forefoot covered with raised, rounded, glandular areas, subarticular tubercles not differentiated from these pustular areas; palmar tubercle larger and well defined. Males with horny excrescence on first and second digits, first usually strongly flexed, with prominent, thick, rounded fleshy hump dorsally, keratinized area wide and extending from tip of digit to its base; second digit with cornified area narrow, extending from base of digit to terminal articulation.

Hind limb short, stout; femoral region spinose on upper thigh only, close to body, rest of limb smooth or slightly wrinkled, occasionally with glandular areas on thigh and crus. Tibiotarsal articulation reaches to points at arm insertion when carried forward along body; heels are separated when tibiofibulae are parallel to femora at right angles to body. Foot fleshy, with very indistinct scattered pustules on sole; webbing fleshy, extends to digit tips as fringe except on first toe, which is almost completely hidden in webbing; webbing between all digits except first and second deeply incised. Outer metatarsal tubercle raised and prominent, inner metatarsal tubercle indistinct.

COLOR IN ALCOHOL.—Dorsum of head, body, and limbs light, may be yellowish, yellow-green, or light brown; occasionally uniform, but usually with few to many irregular, scattered, dark brown to black spots. Dark dorsolateral line begins on side of snout just below fleshy fold, runs through eye and across temporal region onto sides, where it may be continuous and broad, narrow and jagged, or almost totally absent. Ventral surfaces unicolor white, yellowish white or yellow; occasional individual with one or two small brown spots on throat or below anus. Spots often present at limb articulations, may extend around limb, but in no instance continuous ventrally. Sole of forefoot always unicolor, sole of hind foot usually unicolor, may be spotted or streaked.

HOLOTYPE.—This specimen conforms with the description given above for the species, where no alternatives are given. In the case of alternatives, it has the following characteristics: snout rounded; dorsum of head slightly concave, temporal region lightly pustulate. Skin on chest and throat lightly spiculate. Dorsum yellowish, with many black spots, dorsum of limbs with black reticulation; two black spots on throat at chest. Measurements of type (in millimeters): snout to vent: 50.4; snout to end of coccyx: 45.0; knee to knee: 34.6; tibiofibula: 17.0; head length: 12.7; head width: 12.6; eye diameter: 4.0; snout to eye: 5.7; interorbital distance: 3.8; width of eyelid: 3.6.

Atelopus bomolochos, the Azuay stubfoot toad or Cuenca jambato frog, is a species of toad in the family Bufonidae. It is endemic to southern Ecuador and known from Cordillera Oriental in the Azuay, Cañar, and Loja Provinces.