Rhinella margaritifera (Laurenti, 1768)

Lavilla, Esteban O., Caramaschi, Ulisses, Langone, José A., Pombal, José P. & De Sá, Rafael O., 2013, The identity of Rana margaritifera Laurenti, 1768 (Anura, Bufonidae), Zootaxa 3646 (3), pp. 251-264 : 257-259

Rhinella margaritifera (Laurenti, 1768)

Rana margaritifera Laurenti, 1768: 30 .

Neotype: MNRJ 71538, adult female ( Figs. 2–3 ), collected in the Municipality of Humaitá (07o30’S, 63o01’W; approx. 60 m a.s.l.; datum WGS84), State of Amazonas, Brazil, on 12 April 1985 by F.L. Franco and B.V.B. Aloise.

Description of the neotype: Body robust; head slightly wider than long, head length 89.8% of head width; head length 31.1% of SVL; head width 34.6% of SVL. Snout mucronate in dorsal view ( Fig. 3 A); in profile ( Fig. 3 B), nearly acute. Top of snout and head slightly concave; canthus rostralis well defined by the canthal crests, curved; loreal region concave. Nostrils lateral, protuberant, slightly directed dorsally and backwards, nearer to the tip of snout than to eyes; internarial distance smaller than the eye-to-nostril distance, eye diameter, upper eyelid width, and tympanum diameter; eye-to-nostril distance slightly larger than the eye diameter, and larger than the tympanum diameter and upper eyelid width; eye diameter larger than the upper eyelid width and tympanum diameter; upper eyelid width 39.5% of interorbital distance. Canthal, antorbital, and supra-orbital crests developed, parietal crest poorly developed; post-orbital crests large, forming conspicuous lateral ledges; distance of extremities of the post-orbital crests larger than head width. Tympanum large, round, with a distinct annulus; tympanum diameter 89.2% of eye diameter. Parotoid glands, in dorsal view, small, triangular, elongated; in lateral view, elliptical, continuous to the post-orbital crest; parotoid gland length slightly larger than the post-orbital crest length. External border of the parotoid gland with a line of pointed tubercles which continues along the lateral side of body to the groin. Five vertebral apophyses salient on dorsum. Lips not flared; eyes visible from below. A Vshaped incision in the maxilar symphysis; a rounded tubercle at the posterior corner of mouth. Vocal sac and vocal slits absent. Choanae small, lateral, widely separated; tongue large, two times as long as wide, free and not notched behind.

Forelimbs robust, forearms as robust as arms; a line of small pointed tubercles along the lateral border of forearm. Hand ( Fig. 3 C) with medium-sized, slender fingers not webbed, in crescent order of size, IV <II <I<III; lateral fringes poorly developed, formed by a line of spinulose tubercles. Fingers tips slightly expanded, smooth, posteriorly delimited on the dorsal and ventral faces by a groove. Palmar tubercle large, rounded, flat, smooth; thenar tubercle approximately one fourth of the palmar tubercle, ovoid, flat, smooth. Subarticular tubercles developed, conical, unique. Supernumerary tubercles of varied sizes, distinct, conical, irregularly distributed on the ventral surfaces of hand and fingers.

Hindlimbs short, robust. Tibia length smaller than the thigh length; tibia length 87.7% of thigh length and 37.3% of the SVL; thigh length 42.6% of SVL; sum of tibia and thigh lengths 80.6% of the SVL; tarsus-foot length larger than the tibia and thigh lengths, 52.9% of the SVL. A line of conical, spinulose tubercles along the posterior borders of tarsus. Foot ( Fig. 3 D) with short toes, moderately robust, in crescent order of size, I <II <V <III <IV; toes not webbed, but extensively fringed. Lateral fringes of toes with a line of spinulose tubercles. Tips of toes in small rounded bulbs, smooth, posteriorly delimited on the dorsal and ventral faces by a groove. Outer metatarsal tubercle small, rounded; inner metatarsal tubercle large, approximately three times the outer, ovoid, with the external border free. Subarticular tubercles small, conical, unique. Supernumerary tubercles distinct, conical, unequal in size, approximately aligned on the ventral surfaces of foot and toes.

Skin on dorsum and limbs granulose, with many tubercles small, rounded, irregularly distributed without forming a defined pattern. Ventral surfaces finely granulose, with many slightly larger granules scattered over the entire surface.

Color of neotype: In preservative, dorsum and laterals of body and limbs uniformly dark grayish brown; a clear brown stripe on dorsum, on the vertebral column, from the tip of snout to vent. Throat and chest gray, with white tubercles irregularly distributed. Belly and ventral surfaces of hindlimbs and forelimbs uniformly clear cream with gray vermiculations and scattered cream tubercles. Proximal ventral surface of thighs gray with white granules. Posterior surface of tarsus to the ventral surface of toes IV and V, gray. Iris yellow, with dense black vermiculations.

Measurements of neotype (mm): SVL 70.7; HL 22.0; HW 24.5; IND 4.3; END 6.7; ED 6.5; UEW 4.7; IOD 11.9; TD 5.8; THL 30.1; TBL 26.4; TAL 14.5; FL 22.9; HAL 16.6.

Remarks: The region of Humaitá was succinctly described by Gottsberger (1978), Caramaschi & Jim (1983), and Caramaschi & Cruz (2001). Humaitá is a small town on the left bank of the Madeira River, 51 m above sea level. It is surrounded on the western side by the far-extending Puciari-Humaitá savannas. To the north and south is the large dry or "terra firme" forests, frequently crossed by small rivers, regionally called "igarapés". Along these streams are the flooded areas with the "várzea" and "igapó" forests. These small rivers of the region drain the local savannas, and bring black water (Sioli 1975). During the dry season, when the water is at its lowest level, the streams are generally narrow, about 1–2 m wide and extensively surrounded by the "várzea" forest. At the rainy season, the white water (Sioli 1975) of the Madeira River invades the "igarapés" about 500–800 m upstream from its mouth, and it is here that a sharp interface between the white Madeira and black "igarapé" waters occurs. At the highest water level, about 10–12 m above the lowest, the “igarapés” are about 100 m wide, invading laterally the "várzea" forest, and it is bordered directly in both sides by the "terra firme" forest. The vegetation of the "várzea" and "terra firme" forests in the region seems to be reasonably undisturbed. Even at the highest water level, most of the tree crowns emerged 5–10 m, and in many cases huge tree trunks rose 15–20 m above the water surface. On the soil of both "várzea" and "terra firme" forests is a thick leaf litter cover, where specimens of Rhinella margaritifera were collected.

The presence of many color patterns is common among the members of the Rhinella margaritifera species group (see, for example, Caramaschi & Niemeyer 2003; Caramaschi & Pombal 2006). Among specimens obtained at the current type locality of R. margaritifera , several patterns of dorsal color were obtained ( Fig. 4 ). The general color varies from brownish cream, grayish brown, to grayish red. The mid-dorsal longitudinal line may be absent (four specimens), narrow (three specimens), medium (one specimen), and wide (four specimens). Dark brown spots on dorsum, lateral to mid-dorsal line, may be absent (four specimens) or present, in variable number, localization, size, and shape (nine specimens).

Figures

FIGURE 2. Dorsal and ventral views of Rhinella margaritifera, neotype (MNRJ 71538, SVL 70.7 mm).

FIGURE 3. Rhinella margaritifera, neotype (MNRJ 71538, SVL 70.7 mm). (A) Dorsal and (B) lateral views of head; ventral views of (C) hand and (D) foot.

FIGURE 4. Variation in dorsal color patterns of Rhinella margaritifera. (A) MNRJ 71538, Humaitá, neotype. (B) MNRJ 71539, Humaitá. (C) MNRJ 28674 Humaitá – Porto Velho Road. (D) MNRJ 71549, Humaitá. (E) MNRJ 71553, Humaitá. (F) MNRJ 71551, Humaitá. (G) MNRJ 71547, Humaitá. (H) MNRJ 71548, Humaitá. (I) MNRJ 28673, Humaitá – Porto Velho Road. (J) MNRJ 71552, Humaitá. (K) MNRJ 71550, Humaitá. (L) MNRJ 28675, Humaitá – Porto Velho Road.