Description
The body of Amazophrynella gardai is small and elongated, but larger than most of the other species in the genus. The snout vent length ranged from 16.01 - 17.77 mm in males, averaging 16.72 mm, and 22.89 - 24.37 mm, averaging 23.86 mm in females. The head is triangular in dorsal and ventral views, and is wider than long. The snout is elongated and acuminated in the lateral view, and truncated in the dorsal view. The nostrils are protuberant and are closer to the snout than to the eyes. The eye is prominent, and its diameter is larger than the internarial distance. The upper eyelid is covered with small granules, and the lower eyelid is reticulated. The tympanum is not visible through the skin, but the skin over the tympanum is covered with tubercles (Mângia et al. 2020).

The palmar tubercle is rounded, and makes up approximately ½ of the palmar surface. There are four rounded supernumerary tubercles, the first of which is fused with the subarticular tubercle of finger I. The relative finger lengths are I < II < IV < III. The subarticular tubercles are distributed with one each in fingers I, II, and IV, and two in finger III (Mângia et al. 2020).

The hindlimbs are slender. The foot is slender and has basally webbed toes. The relative toe lengths are I < II < III < V < IV. The outer metatarsal tubercle is small and rounded and the subarticular tubercles are rounded in toes I and V, and elliptical in II, III, and IV. The subarticular tubercles are distributed with one each in toes II and V, two in toe III, and three in toe IV (Mângia et al. 2020).

The dorsal skin is spiculated. The skin is fairly tuberculated in the gular region and ventral region. Tubercles are also abundant on forelimbs and hind limbs, and the cloacal opening is slightly above the midlevel of the thighs. The thigh to tarsus region is covered with spiny protuberances (Mângia et al. 2020).

At the time of this description, the genus Amazophrynella already had 12 small-sized species, but there was discussion among the scientific community about the genus harboring several additional species. Based on molecular data and morphology, this new species, A. gardai was added to the clade. The differentiating factors of this species was a large size for the genus. In addition to the large relative size, A. gardai has a large palmar tubercle, which occupies ½ of the palmar surface. Although A. bilinguis, A. teko, and A. xinguensis share this large palmar tubercle, all nine other species in the genus have a palmar tubercle that occupies only ¼ of the palmar surface. However, it differs from A. teko and A. xinguensis due to its rounded palmar surface, as opposed to A. teko’s elliptical palmar surface and A. xinguensis’ ovoid palmar surface. Additionally, A. gardai differs from A. bilinguis due to its finger I being shorter than finger II, whereas A. bilinguis has finger I longer than or equal to finger II. Amazophrynella gardai also differs from all 12 other species through its spiculated dorsal skin. The ventral color of A. gardai is white with small dark brown blotches, and differs significantly from the other species of Amazophrynella, excluding A. manaos, A. bokermanni, and A. bilinguis. Lastly, A. gardai differs from A. teko and A. manaos by the presence of a truncated snout (Mângia et al. 2020).

In life, females have a reddish dorsal color, and males have a dark brown or dark grey dorsal color. Adults typically exhibit a thin white vertebral line from the tip of the snout to the cloaca. From a lateral view, this line extends from the tip of the snout through the lip, the prolateral surface of the upper arm, and to the elbow joint. There are several small white dots on the flanks and dorsal region of the hind limbs. The venter has large black blotches on a predominantly light-colored background (Mângia et al. 2020).

In preservation, the dorsal surface turned pale brown in color. The ventral surface pattern matched that of the coloration in life (Mângia et al. 2020).

There appears to be some variation with the vertebral line, as one of the males did not have the same thin white line along the vertebrae as the other specimens. There also seems to be some sexual dimorphism, as the females were on average larger than the males in all measurable aspects, and have a reddish dorsal color whereas the males are dark brown or dark grey in dorsal coloration. The gular region also varies between males and females, from dark brown to light brown in color (Mângia et al. 2020).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Brazil

View distribution map in BerkeleyMapper.

At the time of the species description, A. gardai was only known from the type locality in Óbidos municipality, Pará state, Brazil. The region was characterized as an Alluvial Forest type, where there are smaller trees and a high concentration of palm trees. Amazophrynella gardai is found in low-elevation (0 - 384 m) regions, and was also near a main river (Mângia et al. 2020).

Life History, Abundance, Activity, and Special Behaviors
Individuals were collected for the species description in February, during the rainy season in the region. Two amplected pairs were discovered, indicating that it may have been mating season for A. gardai. However, no males were observed engaged in calling activity, and it is possible that this species does not attract mates by calling (Mângia et al. 2020).

Individuals were found by visual search and pitfall traps in the forest, ranging from 500 up to 2,000 m from the edge. During visual searches, three males, one female, and an amplected pair were found. These individuals were found on leaf litter in “Terra firme,” near rivulets in the forest, and were found to be most active in the mornings, between 8:00 and 11:00. From the pitfall traps, one female and one amplected pair were collected (Mângia et al. 2020).

When being photographed, one male individual exhibited thanatosis, or death-feigning, by stiffening its legs. This stiff-legged behavior is a defense mechanism, to avoid detection by predators (Mângia et al. 2020).

Comments
The species authority is: Mângia S., Koroiva, R., Santana, D.J. (2020). "A new tiny toad species of Amazophrynella (Anura: Bufonidae) from east of the Guiana Shield in Amazonia, Brazil." PeerJ 8: e9887.

Genetic analysis was done on the COI, 16S, and 12S rDNA mitochondrial genes using Bayesian Inference. The genetic analysis revealed that A. teko and A. manaos are the closest phylogenetic relatives to A. gardai. Three main clades were recovered in the phylogenetic analysis of Amazophrynella species, with A. gardai falling into a clade composed of A. gardai, A. teko, A. manaos, and an undescribed Amazophrynella species. Amazophrynella gardai was identified a sister taxon of the other species. Among these species, A. teko is sister to the undescribed Amazophrynella species. Together they form a sister clade to A. manaos and the clade containing these three species is sister to A. gardai. The clade containing A. gardai is a sister to a clade comprised of A. bokermanni, A. vote, A. bilinguis, and A. xinguensis. The third clade is sister to the first and second clades, and is comprised of A. moisesii, A. matses, A. minuta, A. siona, and A. amazonicola (Mângia et al. 2020).

The species epithet, “gardai”, is a patronym honoring Professor Adrian Antonio Garda for his extensive contributions to the knowledge about Neotropical frogs. He was also a good friend and mentor to Sarah Mângia and Diego José Santana, two of the authors who described A. gardai (Mângia et al. 2020).

References

Mângia, S., Koroiva, R., Santana, D. J. (2020). ''A new tiny toad species of Amazophrynella (Anura: Bufonidae) from east of the Guiana Shield in Amazonia, Brazil.'' PeerJ, 8(9887), 21. [link]

Species Account Citation: AmphibiaWeb 2021 Amazophrynella gardai <https://amphibiaweb.org/species/9260> University of California, Berkeley, CA, USA. Accessed Apr 19, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 19 Apr 2024.

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