Evergreen Toad

Bufo coniferus adult males measure 53-72 mm and adult females 76-94 mm in SVL. The head is broader than long and subovoid when viewed from above (Savage 2002). The snout is widened at the tip and has a small vertical ridge when viewed from above. In profile, the snout is nearly truncate, and the upper jaw extends well beyond the lower. Nostrils are dorsolateral and strongly projecting, closer to the snout tip than to the eyes. Eyes are large and the diameter is equal to the distance between the orbits and the tip of the snout (Cochran and Goin 1970). The skin of the head is co-ossified to the upper skull bones, and this toad possesses well-developed black canthal supraorbital, postorbital, parietal, and supratympanic and pretympanic crests. In contrast, the labial crest is poorly indicated and the preorbital and suborbital crests are variable. The parotoid gland is highly variable in shape, being elongate, ovoid, or triangular. It is covered with spinous warts and often obscure or barely larger than adjacent warts (Savage 2002). The tympanum is distinct, with the greatest diameter about half the diameter of the eye; it is separated from the eye by a space approximately one third of its own diameter. Body shape is stout, and there is a slight skinfold across the chest (Cochran and Goin 1970). The dorsal surfaces of B. coniferus are covered with widely spaced dark-tipped pointed warts and spicules. A longitudinal series of large dark-tipped spinous warts cover the flanks, and spinous tubercles cover the underside except for the abdomen (Savage 2002). The fingers are long and slightly webbed with lateral ridges. Finger II is longer than Finger I, and Finger IV is longer than both (Cochran and Goin 1970). The subarticular and supernumerary tubercles under the fingers and toes are low, rounded to flattened, and usually single and at times bifid (Savage 2002). A small triangular thumb pad and large squarish palmar callus are present. The metacarpal tubercles are well-developed and single (Cochran and Goin 1970). The toes have moderate webbing, and Toe III is slightly longer than Toe V (Savage 2002; Cochran 1970). The inner metatarsal tubercle is small, the outer tiny or absent (Savage 2002). There is a heavy skinfold on the heel and knee (Cochran and Goin 1970). Adult males have one or two vocal slits and a fully distensible single internal subgular vocal sac, which is round when inflated. Dark brown nuptial pads are present on the upper surfaces of Fingers I and II of adult males (Savage 2002). Dorsal coloration is usually yellow green to olive green, although sometimes dull gray to brown. The color is uniform or with contrasting dark or white blotches, or dark blotches with one or two gold spots. Small juveniles (up to 30 mm SVL) are usually green with light outlined red orange warts. The venter is dirty white. The iris is green and brown. (Savage 2002). Larvae at stage 36 measure 19.7-21.3 mm SVL. The body is ovoid with an average width of 5.6 mm, and it is widest at 1/3 the distance back from the tip of the snout; the tail is longer than the body. The snout is rounded in the dorsal profile, and the tail tip is rounded. The nostrils are dorsal and eyes dorsolateral. The spiracle is sinistral, is closer to the posterior end of the body, is located at the midbody, and directed posteriodorsally at a 45° angle. The vent tube is medial. The mouth is moderate and anteroventral. The oral disc is emarginate with the papillae of the upper labium confined to the corners of the mouth; on the right side there are 10-13 small papillae in the outer row and 3-6 inner, and on the left side there are 10-11 outer and 2-4 inner. The lower labium is also free of papillae except at the corners; on each side there are 9-15 papillae. Beaks are finely serrated, and the upper beak is very slightly convex while the lateral portions are sharply angled downward. The lower beak is shallowly V-shaped. There are 2/3 denticle rows, with both upper rows extending completely across the mouth from under the lateral papillae and the lower row slightly longer and separated above the beat by 1/4-1/3 the length of the beak. The lower denticle rows are complete with the longest at the top of the oral disc and each of the next lower slightly shorter than the preceding (Livezey 1986). In life, the tadpoles are black above and gray below. The dorsal fin is slightly more heavily pigmented than the ventral, and both the caudal and dorsal fins are relatively clear and translucent. The tail musculature is dorsally very heavily pigmented from 3/4 to almost the entire depth; the portion without pigment is creamy-white to gray. In preservative, the dorsal body coloration is deep brown with black pigment blotches laterally and anteriorly. The venter is gray with the intestinal coil clearly visible (Livezey 1986).The karyotype is 2N = 22, with six large and five small pairs of chromosomes that are all metacentrics or submetacentrics (Bogart 1972). A Spanish-language species account can be found at the website of Instituto Nacional de Biodiversidad (INBio) (http://darnis.inbio.ac.cr/FMPro?-DB=UBIpub.fp3&-lay=WebAll&-Format=/ubi/detail.html&-Op=bw&id=4372&-Find).

Bufo coniferus is distributed along humid lowlands and premontane slopes from eastern Nicaragua on the Atlantic versant and southwestern Costa Rica on the Pacific slope south to western Colombia and northwestern Ecuador. It is present up to 1,550 m above sea level (Savage 2002). This toad is commonly found in lowland wet and moist forest zones, and is less frequently found in premontane wet forest and lower montane wet forest zones. It is usually in undisturbed forests and is often climbing above the ground on shrubs or trees (Savage 2002).

This is a nocturnal, scansorial toad with an unusual life history trait for toads: it is often found hiding or climbing in vegetation (trees or vines); Duellman and Schulte (1992) reported seeing this species up to 1.5 m above ground while Savage (2002) reported it as climbing up to several meters above ground. Other arboreal toads include Bufo (Rhinella) arborescandens, Bufo (Rhinella) manu, Bufo (Rhinella) tacana, Bufo (Incilius) valliceps, and Bufo (Rhinella) yanachaga. Species that are at least partially arboreal include B. chavin, B. multiverrucosus, B. nesiotes, and B. veraguensis (see Chaparro et al. 2007 for sources). Bufo coniferus breeds in shallow ponds or pools in the forest or nearby pastures during the dry season (December to April). During the reproductive season, male choruses may be heard during the day as well as at night, and males call from the edge of a pond or pool (Savage 2002). The call is a long trill lasting 18-30 seconds with a dominant frequency of 1.0 kHz, and the trill rate is 39-40 per second (Porter 1966). Large choruses sound like gasoline-powered generators. Amplexus is axillary (Savage 2002). Oviposition occurs at the beginning of the wet season, and the eggs are often deposited in temporary ponds or water-filled depressions that form after heavy rains (Crump 1989). Double rows of eggs without partitions are laid within a continuous, double-layered gelatinous tube. The eggs are black on the upper 2/3-3/4 and gray on the lower portion. Average diameter of eggs is 1.77 mm (ranging from 1.67-1.86 mm), and there are 12-16 eggs per 2.00 cm. Average diameter of the egg capsule is 1.85 mm. The encasing tube consists of a thin outer envelope surrounding a second inner envelope. Average diameter of the outer envelope and inner envelope are 4.16 mm and 3.71 mm, respectively. Occasionally, there may be single and triple rows of eggs; the average diameter of eggs in single rows and triple rows are 1.70 mm and 1.76 mm, respectively. Eggs hatch in about five days, resulting in tadpoles at stages 19 to 21 with a SVL of 5.95-6.95 mm, fully developed gills, opaque cornea, developing oral disc, and obvious suckers. Metamorphosis is achieved 33 days from hatching, resulting in a toadlet with an SVL of 9.1 mm. (Livezey 1986). Small juveniles are 14 mm (Savage 2002). This species appears to feed almost entirely on ants and mites (Toft 1981).

Although this species' population trend is listed as stable by the IUCN, a study by Lips et al. (2003) gives this species a high probability of decline (0.73), most likely due to its large size and dependence on riparian habitats. It is most common in Costa Rica and Panama. It occurs within a number of protected areas throughout its range.