Oak Toad — Part 3

Bufo quercicus Holbrook

Range.—Bufo debilis is reported from the following places in Texas: Upper Wichita River, Nueces River, Lower Rio Grande, and the Brazos (Waco).

This is said to be the smallest known toad. It is a little, dusky, hopping creature, which has probably been mistaken many times for the young of Bufo lentiginosus, the Southern toad. It is so small that we need a lens in order even to make out many of the details of its appearance. This is especially true of the crests of the head. They are obscure not only because of their small size, but also because of their dusky colour and the warty condition of the surrounding surface.

The eye has a shining golden iris. Its expression indicates much alertness. The ear is round and conspicuous, although it is much smaller than the eye.

It is said (Loennberg. Notes on Reptiles and Batrachians collected in Florida in 1892 and 1893. Proc. U. S. Nat. Museum, vol. XVII, pp. 317, 339.) that this toad may be seen in all kinds of places and at all times of day; that it is out during the brighest sunshine as well as at dusk and after rains. It was first found in sandy places, where there were low growths of oak-hence its name, "Oak Toad."

After heavy rains, Oak Toads resort in large numbers to shallow pools. They are difficult to see, but give notice of their presence by an ear-splitting chorus of high-pitched sounds. (C. B. Lungren, collector. Ozona, Fla.) The individual call is like that of a young chicken in distress, but considerably louder. The male alone gives the call, and while producing it seems to have in his mouth a transparent bladder about the size of a man's thumb. The fact is that this toad has a large vocal bladder that can be extended from the midline of the lower throat region. This structure relates it to Bufo compactilis and Bufo cognatus of the Southwest.

When taken in the hand, the Oak Toad gives a rather musical chirping sound, like that of a young bird.

There would never be any possibility of confusing this toad with any other. Its green colouration and its smooth skin identify it at once. It is peculiar, also, in attaining a size greater than that of any other North American species. In addition to these, the toad has the following other distinctive characteristics: the conspicuous glands on the legs, the peculiar white warts at the angle of the jaw, the curving crests of the head, and the greatly diverging parotoid glands.

The parotoid glands, beginning immediately back of the eye, are so long and descend on the shoulder so much that when they are only three-fourths of an inch apart at their anterior ends, they may be separated at their posterior ends by a distance more than twice as great. The parotoids are about the same width throughout their length. The elevated shoulder-blades show plainly on the back between them.

The bony crests of the head are smooth and rounded. Although not greatly elevated, they are very conspicuous, because of the smoothness and even colour of the surrounding surface. The crests extend backward from the nostrils in front, diverge and encircle the eyes. There is a crest under each eye in front, and another short one passes forward over the ear, on each side. The skin between the crests on the top of the head is thin and adheres to the bone underneath.

The ear is unusually conspicuous. It is placed immediately back of the eye, under the anterior part of the parotoid gland, and is surrounded by a prominent ridge. The eye is large and gentle in its expression. The iris is peculiar in having its metallic yellow thickly set with a tracery of bright red veins. There are two curious elevations in the gold of the iris; they are situated in the midline of the eye at the margin of the iris, immediately above and immediately below the pupil. The eyelid is smooth, but is thickened, and presents a prominent angle at each extremity.

The upper jaw projects beyond the lower so that the nostrils are set anterior to the vertical line of the mouth-opening. The oval nostrils are large; they open upwards and backwards. The inner finger of the male is thickened at the base, and the brown inner and upper surfaces of the first and second fingers are hard and horny.

When it is held in the hand, this toad jerks spasmodically, and vibrates the whole body, as if about to explode with wrath. The only sound, however, produced in protest is a gentle chirping note, less loud and emphatic than that of the American toad.