The Second Collection of, and Variation in, the Rare Neotropical Toad Bufo peripatetes

Abstract

In 1923, Helen Thompson Gaige collected a single, large (70 mm snout-vent length) male toad (UMMZ 58430) from the Atlantic slopes of upland western Panama (above Boquete, Chiriqui Province on the trail to Almirante, 1500 m). This animal was considered to be Bufo simus by Taylor (1951). Savage (1972) showed that the name B. simus cannot be applied to any North or Central American species, and proposed that the Panama toad represented a distinct species, B. peripatetes. Recently, our attention was directed to a series of toads obviously conspecific with the holotype of B. peripatetes from a second locality, Cerro Bollo, about 80 km ESE of the type locality, on the border between Chiriqui and Bocas del Toro Provinces, about 23 km NNE of San Felix, Chiriqui Province in the area of Escopeta Camp, between 1800-1856 m. These toads were collected during June and July 1980 by R. J. Izor. This sample (USNM 297523-34) includes a series of five adult females (USNM 297525-29), four juveniles (USNM 297523, 297530, 297532, 297534), and three adult males (USNM 297524, 297531, 297533), and permits us to present information on variation, including ontogenetic changes and sexual dimorphism for the species. The toads from Cerro Bollo agree with the holotype (condition in parentheses) except that: (1) the thenar tubercle is wider than the palmar tubercle in five examples, and as wide as the palmar in one (palmar larger than thenar); and (2) the length of the parotoid gland is greater than 75% of the upper eyelid length in seven toads (length of parotoid 75% upper eyelid length). As predicted by Savage (1972), there is marked sexual size dimorphism; females are longer (SVL) than males with proportionally smaller parotoid glands, shorter heads, and longer tibiae (Table 1). The color pattern of males from Cerro Bollo is similar to that of the holotype. The dorsa are uniform tan; the dorsal surfaces of the limbs are tan, with or without vague darker blotches or spots (Fig. 1); the flanks have vague gray marks or distinct dark spots in the groin; the posterior thigh is tan with a few dark spots near the knee, and there is an ocellus-like spot at the knee (light spot completely surrounded by black) in USNM 297531; and the ventral surfaces are tan with a few dark spots on the chest and legs. According to Izor's field notes, the dorsal color of the males is lemon yellow in life. When originally seen two years after preservation, the males were pale yellow and areas now tan or light brown in preservative were of this hue in life. The male holotype (UMMZ 58430) may have been yellow in life but no mention of color is included in the field notes that originally accompanied the specimen. This example has more dark pigment on the groin and thigh areas than the Bollo males, but otherwise does not differ from them