Gopher Frog

Rana aesopus Cope

Colour.—Brown, dark or light in shade. This colour may be purplish, greyish, or yellowish in tone. The broad lateral folds are bright orange-yellow. Warts on back and sides, often bright yellow. Many closely set black spots on the head and on the back between the lateral folds; many smaller black spots on the sides. The spots on the back and on the sides infringe upon the yellow lateral folds. Upper lip spotted, not light or dark bordered. Ear dark, with irregular spot of light in centre. Glandular fold along jaw to shoulder yellowish. Legs with four or five black or dark brown cross-bars. Foot and hand dark; tubercles of hands and feet light in colour. Underparts spotted, especially anteriorly. (See Colour Plate XIV.)

Measurements.—Size medium to large, i.e. length 2 1/2 to 4 inches; female larger than male. Head long, its length contained two and a half times in total length. (Fig. 226.) Head of a frog 3 inches long measures 1 1/2 inches wide and 1 1/4 inches long. Length of leg to heel equal to length of body forward to ear or eye. Femur and tibia about equal. Foot long, fourth toe extremely long; web medium in size.

Structure.—Body peculiarly short and squat. Skin leathery, and corrugated with elongated wart-like folds on back and sides. Tibia ridged lengthwise. Lateral folds broad and elevated. The glandular folds of the jaw end above the shoulder in peculiar large warts. Ridge from eye to shoulder (over ear) inconspicuous. Eye unusually large and prominent. Nostril equidistant between eye and jaw. Ear a vertical oval, half to two-thirds size of eye. Space between eyes less than width of eyelid. Fingers long and slender; the thumb of the male is thickened and horny at its base (Fig. 228); hand tubercles not notable for size. Legs stout and strong; inner sole tubercle relatively large and long, outer small or lacking; tubercles under joints of toes rather conspicuous.

Range.—Rana aesopus Cope is reported from Florida only (Micanopy, Orlando, Ozona, Lake Jessup, Clarcona).

Colour.—Brown posteriorly; lighter anteriorly, often bright metallic green, especially on sides of head under the eyes and below the canthus rostralis. Iris golden. Ear bronze. Lateral folds light yellowish brown. Three or more irregular rows of spots between the lateral folds, and many spots placed irregularly below the folds. Spots light edged or not. Legs light brown, spotted with dark, even on the feet. Underparts white, yellow posteriorly. (See Colour Plate. II.)

Measurements.—Size medium, i.e. length 2 to 3 inches. Leg short; length of leg to heel equalling length of body forward to eye. Tibia but slightly longer than femur.

Structure.—Skin smooth, except for lateral folds and a few inconspicuous elongated wart-like elevations on the back between the lateral folds and on the sides. Head rounded, thick through, with much the proportions and appearance of the head of Rana clamitans. (Fig. 257.) Ear larger than eye in male, slightly smaller than eye in female. No conspicuous ridge over ear. No glandular fold along jaw. Feet delicate; webs broad and long. Inner sole tubercle small; outer lacking.

Range.—Rana onca Cope is reported from Utah and Nevada.

The Gopher frog of Florida is very different from other frogs in its general appearance. It is squat and toad-like, having an unusually large head, with a prolonged muzzle, and eyes prominent and bulging even for a frog. Because of the unusual length and breadth of head, this frog has a mouth relatively larger than those of other North American frogs. (Fig. 227.) These structural characteristics give the frog so peculiar an appearance that although it may agree with Rana palustris and with Rana pipiens in colour and in being prominently spotted, there would never be any difficulty in distinguishing it as a different species. (See Colour plates XI, XIII and XIV.)

The male frog has two large vocal pouches (one at each shoulder). These can be extended between the arm and the glandular fold above. When the pouch is not inflated, the region back of the angle of the jaw and between the arm and glandular fold (which extends fully one-half inch behind the jaw angle) is occupied by broad folds of thin dark-coloured skin.

The general colour of these frogs varies considerably. It may be grey or brown, somewhat yellow or purple in tone. The spots may vary in size and in number. In any individual frog, the colour changes are striking and rapid. The frog may change from nearly black to white, through shades of brown or purplish grey. The spots keep their intensity when the frog is light in colour. (Colour Plate XIV.) In the light-coloured frog, yellow colour is very prominent. It is not only on the elongated warts and lateral folds, but extends from the lateral folds over the eyes along the canthus rostralis to the nostrils. The secretion of the skin given off when the frog is annoyed is offensive in odour.