Comprehensive DescriptionRead full entry
Pseudoeurycea bellii is the largest of the lungless salamanders (family Plethodontidae) and one of the largest terrestrial salamanders, with a maximum size of 36 cm in total length. Pseudoeurycea bellii has a stout body, long, muscular limbs, and a long tail, constricted at the base. The tongue is projectile. This salamander has shiny dark black skin with two red to red-orange spots on the occipital area (back of the head) generally present. The subspecies P. b. bellii has a dorsal mark in the shape of a chevron, generally followed by paired rows of red to red-orange spots (sometimes joined into chevrons) running along the back, down to the base of the tail. In contrast, the subspecies P. b. sierraoccidentalis (found in northern Mexico, in an area straddling the border of Sonora and Chihuahua) has greatly reduced reddish coloration, with asymmetric and irregular small dorsal markings (Parra-Olea et al. 2005).
This species can be distinguished from P. boneti by having a smaller amount of reddish coloration: P. bellii usually has paired rows of dorsal markings (vs. fused into large chevrons, often interconnected, in P. boneti) and lacks a pair of large scapular spots (vs. present, lateral to the row of chevrons and often connected to them in P. boneti); it can be distinguished from P. maxima by having a narrower head and shorter limbs, having a greater amount of reddish coloration (a conjoined occipital spot, which is absent in P. maxima, and larger dorsal spots, vs. smaller dorsal dots in P. maxima); from P. naucampatepetl by having dark red or orange coloration (pale pinkish in P. naucampatepetl), lack of a triangular shoulder spot (present in P. naucampatepetl) and lack of a broad U-shaped spot posterior to the insertion of the hindlimb (present in P. naucampatepetl); from P. gigantea by the presence of large red occipital spots (generally absent in P. gigantea) and a preference for drier habitat (vs. wetter forests and cloudforests for P. gigantea) (Parra-Olea et al. 2005).
This species was first described by Gray (1850), as Spelerpes bellii. Two subspecies were recognized by Lowe et al. (1968): P. b. sierraoccidentalis (straddling the border of Sonora and Chihuahua in northern Mexico) and P. b. bellii (in central Mexico, with isolated populations ranging from the Sierra Madre Oriental in the state of Tamaulipas to the Sierra Madre Occidental in Nayarit and Zacatecas and central Guerrero). It is part of a species complex; Oaxacan populations have been placed into the resurrected species P. boneti (eastern and northern Oaxaca) and into the new species P. maxima (Putla area, western Oaxaca) by Parra-Olea et al. (2005). Populations in Tamaulipas differ in color and morphology and some may represent yet another cryptic species in this complex (Parra-Olea et al. 2005; Alvarez and Martín 1967).