Description
Stereocyclops palmipes is a medium size microhylidae frog, with a snout-vent length ranging from 43.7 to 48.5 mm in males and 48.4 to 56.7 mm in females. They have a robust and ovoid body, and a small head. The snout is short and rounded in dorsal view, protruding in lateral view, and nostrils are located at the tip of the snout, directed laterally. The eyes are small and not prominent, with an indistinct tympanum. The arms are robust. The hand is large and robust, with slender fingers and no interdigital membranes. The legs are robust, with the tibia slightly smaller than the thigh. The feet are robust, with developed fringes and interdigital membranes. The fringes and interdigital membranes of the toes are well-developed, being slightly larger in males (with a plantar webbing formula of I 2+ – 3+ II 2^- – 4+ III 3 – 3^- IV 3^- – 2+ V) compared to females (with a plantar webbing formula of I 2+ – 3 II 2^- – 4+ III 4+ – 4+ IV 4+ – 2+ V). The dorsal surface is smooth, and numerous dermal spines are concentrated on the inferior border of the mandible, forming a band. In males, there is a concentration of large dermal spines along the inferior border of the mandible, forming a distinctive band. (Caramaschi et al. 2012).

DIAGNOSIS:

Stereocyclops palmipes can be differentiated from both S. incrassatus and S. parkeri by the well-developed interdigital membranes on its feet, a feature absent or vestigial in the latter two species. Furthermore, S. palmipes stands apart from S. parkeri due to the presence of prominent mandibular, ventral, and pericloacal dermal spines. In contrast, S. parkeri has small dermal spines that are visible only under magnification, and they are few and scattered. Another distinguishing factor is the color pattern, with S. palmipes exhibiting mid-dorsal dark stripes that converge and unite before the occipital dermal fold, forming an arrow-shaped dorsal pattern, a feature not observed in S. parkeri (Caramaschi et al. 2012).

COLORATION:

The main color of the dorsum, presumably in preservative, is light grayish-brown, while the venter is dark brown, with clear boundaries between them. The color pattern consists of two vaguely defined dark brown stripes running along the middle of the dorsum, starting from the inguinal regions and extending to the head. These stripes pass over the occipital dermal fold and reach the upper eyelid. There is also a cream-colored line from the tip of the snout to the vent, and the dorsal surfaces of the thighs and tibiae have transversal brown bars. The gular region is gray, and there's a cream-colored line running lengthwise on the ventral surface from the front edge of the mandible to the vent. Additionally, there's a transversal, V-shaped cream line on the pectoral region, along with cream lines bordering the posterior surfaces of the arms, thighs, tibiae, and feet (Caramaschi et al. 2012).

VARIATION:

Females exhibit a greater size compared to males. The dorsal background color spans a range from light gray to dark brown. Anastomosed brown marks on the dorsal side may be outlined by dark brown lines. Ventral coloration varies from dark brown to dark gray, and small scattered cream spots may be present on the ventral region. Dermal spines are scattered across the ventral surfaces of the body, arms, fingers, legs, toes, and pericloacal region in males, while in females, they agglomerate in the pericloacal region and ventral surfaces of the thighs (Caramaschi et al. 2012).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Brazil

View distribution map in BerkeleyMapper.

Stereocyclops palmipes is endemic to Brazil. It can be found in elevations ranging from 219 - 408 m.a.s.l. in the inland areas of the State of Minas Gerais in southeastern Brazil, specifically in the region known as "Zona da Mata". This region is characterized by low montane semidecidual forest (Caramaschi et al. 2012).

Life History, Abundance, Activity, and Special Behaviors
Other anuran species found in the same region include Dendropsophus anceps, D. bipunctatus, D. branneri, D. elegans, D. minutus, Elachistocleis cesarii, Hypsiboas albomarginatus, H. faber, H. semilineatus, Itapotihyla langsdorffii, Rhinella pombali, Scinax argyreornatus, S. eurydice, Leptodactylus (Adenomera) sp., L. fuscus, Leptodactylus latrans, L. spixi, Physalaemus cuvieri, and Physalaemus gr. signifer (Caramaschi et al. 2012).

Comments

PHYLOGENETIC RELATIONSHIPS:

References
Caramaschi, U., De Oliveira Lula Salles, R., and Cruz, C. A. G. (2012). A new species of ,Stereocyclops Cope (Anura, Microhylidae) from Southeastern Brazil. Zootaxa, 3583, 83–88. [link]

Species Account Citation: AmphibiaWeb 2024 Stereocyclops palmipes <https://amphibiaweb.org/species/7958> University of California, Berkeley, CA, USA. Accessed May 12, 2025.

Citation: AmphibiaWeb. 2025. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 12 May 2025.

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