Description
Adelophryne glandulata is overall a small frog with an adult snout-vent length that is typically less than 11 mm for most individuals but may be up to 14 mm in some cases (Lourenco-De-Moraes et al. 2014; Silviera et. al 2019). Females are typically larger than males with females having a snout to vent length range of 11.5 – 13.1 mm, whereas male snout-vent length range is 10.1 – 10.9 mm. The head is about as wide as it is long but is narrower than its body. The cranial crests are not present on the top of the head. However, there is a glandular ridge line running from the back part of the eye to where the forelimb meets the body. The tympanum is not visible nor is a tympanic membrane. It also lacks a tympanic annulus. The skin on the belly is smooth, while the skin on the dorsum is shagreened with small, rounded tubercles (Lourenco-De-Moraes et al. 2014; Silviera et. al 2019). The anal flap is absent. The phalangeal formula for the fingers on the forelimbs is 2 – 2 – 3 - 2 and the relative finger lengths are I = IV < II < III. Instead of terminal discs, the fingers are T-shaped and the points are slightly mucronate. Finger I is also distinctly shorter than finger II and finger IV has a single subdigital pad. The phalangeal formula for the toes on the hindlimbs is 2 – 2 – 3 – 4 - 3 and the relative toe lengths are I < V < II < III < IV. The toes have terminal or vestigial discs with circumferential grooves. Like the fingers, the toes are T-shaped and have slightly mucronate ends. Subarticular tubercles are absent on the toes, but subdigital pads are present in a formula of 1 – 1 – 2 – 3 – 1 (Lourenco-De-Moraes et al. 2014).

DIAGNOSIS:

Adelophryne glandulata can be differentiated from other species in its genus by its smaller size. The maximum snout to vent length recorded for A. glandulata is 14 mm (Silviera et. al 2019) Additionally, A. glandulata’s shagreened dorsum with small, rounded tubercles sets it apart from A. baturitensis, A. meridionalis, A. pachydactyla (which are smooth), A. mucronatus (smooth with scattered small granules), A. adiastola (shagreened to granular), and A. patamona (tuberculated). Adelophryne glandulata has an indistinct tympanum, setting it apart from: A. baturitensis, A. adiastola, A. gutturosa, A. maranguapensis, A. mucronatus, A. pachydactyla, and A. patamona, which all having distinct tympanums (Lourenco-De-Moraes et al. 2014). Adelophryne glandulata has the unique subdigital pad formula of 1 – 2 – 2 - 1 not seen in any other species in the genus: A. pachydactyla is 2 – 3 – 4 - 2; A. maranguapensis is 1 – 1 – 2 - 2; A. adiastola, A. gutturosa, A. meridionalis, and A. patamona are 1 – 1 – 2 - 1; A. mucronatus is 1 – 2 – 3. - 1. Adelophryne glandulata has two phalanges in finger IV (rather than three), setting it apart from A. baturitensis, A. gutturosa, A. maranguapensis, A. mucronatus, and A. patamona (Lourenco-De-Moraes et al. 2014).

More specifically, A. glandulata lacks the discs or circumferential grooves on its fingers seen in A. baturitensis and A. maranguapensis. Adelophryne glandulata has subdigital pads, but lacks the subarticular tubercles seen in A. baturitensis. And A. glandulata has disc on toes II, III, IV and V with circumferential grooves, while A. meridionalis only has circumferential grooves on toe IV. Adelophyrne meridionalis also lacks the glandular ridge line and small tubercles which A. glandulata possesses (Lourenco-De-Moraes et al. 2014; Silviera et. al 2019).

*Hidden because, where did this come from?!?* while others in the genus are as follows: A. baturitensis - 16.3 mm, A. gutturosa - 16.0 mm, A. maranguapensis - 17.4 mm, A. mucronatus - 14.9 mm, A. patamona - 23 mm. The presence of a glandular ridge also serves as a distinctive characteristic since the only other species having it is A. gutturosa which is larger than typical A. glandulata individuals.

COLORATION:

VARIATION:

The dorsal coloration of A. glandulata can vary from golden brown to dark brown, to reddish-brown. There is no sexual dimorphism when it comes to coloration but there is some sex based differences in the variance of limb and head features. Hindlimb-length of males vary more than females. Females vary more in head feature measurements than males. There is also variance in the number or presence of the rounded glandular series posterior to the eye (Lourenco-De-Moraes et al. 2014).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Brazil

View distribution map in BerkeleyMapper.

Adelophryne glandulata is found in moist, semi-deciduous forested areas in the Santa Teresa municipality, State of Espírito Santo, Southeastern Brazil between 666 – 1038 m elevation. It has also been found near the Piracicaba River and Gualaxo do Norte River region in Mariana and Ouro Preto, Quadrilátero Ferrífero region; central mountainous region of Itabira, Quadrilátero Ferrífero; and Parque Estadual do Rio Doce, in the Vale do Rio Doce (Lourenço-De-Moraes et al. 2014; Silveira et al. 2019).

Life History, Abundance, Activity, and Special Behaviors
Reproduction is likely to occur in leaf litter since this species is commonly observed on the forest floor (Lourenco-De-Moraes et al. 2014).

Although vocal sacs are present in this species, as of 2021, no audible calls have been reported (Lourenco-De-Moraes et al. 2014).

Females have been observed carrying eggs in November, which suggests that reproduction occurs during the rainy season. Observed egg clutch sizes were estimated to contain three to eight eggs with an average size of 2.0 mm in diameter. Due to the relatively large egg size and small clutch size, they are expected to exhibit direct development (Lourenco-De-Moraes et al. 2014).

This species, when threatened, displays short, quick, and multidirectional hops to flee from predators. Due to their dorsal cryptic coloration, they may also rely on camouflage. This species may partake in mouth gaping, but it does not have any defensive vocalization nor has been seen biting (Ferreira 2019).

Observed prey includes ants and beetles (Lourenco-De-Moraes et al. 2014).

Trends and Threats
Since this species is heavily dependent on densely-forested habitats, it is highly susceptible to habitat loss (Ferreira 2015). Lourenco-De-Moraes et al. (2014) recommend that the Terensis flea frog be listed as “Endangered” because of its small distribution that continues to decrease due to habitat loss and climate change. However, Silveira et al. (2019) expanded the known geographic range of the species, including in three conservation units, and cautiously recommends a reassessment of the species' threat status. They also emphasize the creation of a conservation unit in Quadrilatero Ferrifero, the only known area it exists that does not include a conservation area.

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Habitat fragmentation
Climate change, increased UVB or increased sensitivity to it, etc.

Comments
There are several unnamed candidate species in the Adelophryne genus. Bayesian Inference and Maximum Likelihood analyses indicate that A. glandulata is a part of the Southern Atlantic Forest clade within the subfamily Phyzelaphyrninae and family Eleutherodactylidae. Within the Southern Atlantic Forest clade, A. glandulata forms a polytomy with an unnamed Adelophryne (sp. 4) and a clade composed of A. mucronata and yet another unnamed Adelophryne (sp. 8). The Southern Atlantic Forest clade is sister to the Northern Atlantic Forest clade, which is composed of A. baturitensis, A. maranguapensis, A. michelin and two unnamed Adelophryne species (Lourenco-de-Moraes et al. 2018).

One of the distinguishing features of this species is the glandular ridge running from the back part of the eye where the forelimb meets the body. Due to this notable characteristic, the species was given the Latin epithet “glandulata”, meaning “glandular” (Lourenco-de-Moraes et al. 2014).

References

Ferreira, R. B., Lourenco-de-Moraes, R., Zocca, C., Duca, C., Beard, K. H., Brodie, E. D. (2019). "Antipredator mechanisms of post-metamorphic anurans: A global database and classification system." Behavioral Ecology and Sociobiology, 73(5), 69. [link]

Ferreira, R.B. (2015). "Ecology, behavior and taxonomy of anurans from Brazil's Atlantic Forest." Utah State University, PhD dissertation. https://digitalcommons.usu.edu/etd/4466/ [link]

Lourenco-de-Moraes, R., Dias, I. R., Mira-Mendes, C. V., Oliveira, R. M. de, Barth, A., Ruas, D. S., Vences, M., Solé, M., Bastos, R. P. (2018). "Diversity of miniaturized frogs of the genus Adelophryne (Anura: Eleutherodactylidae): A new species from the Atlantic Forest of northeast Brazil." PLOS ONE, 13(9), e0201781. [link]

Lourenco-de-Moraes, R., Ferreira, R., Fouquet, A., Bastos, R. (2014). "A new diminutive frog species of Adelophryne (Amphibia: Anura: Eleutherodactylidae) from the Atlantic Forest, southeastern Brazil." Zootaxa, 3846(3), 348–360. [link]

Silveira, A. L., Rievers, C. R., Ribeiro, L. S. V. B., Dornas, T. T., Fernandes, T. N. (2019). "Taxonomic identity of Adelophryne (Anura, Eleutherodactylidae) populations in the Atlantic Forest in Minas Gerais, Brazil." Herpetology Notes, 12, 311-317. [link]

Species Account Citation: AmphibiaWeb 2021 Adelophryne glandulata: Teresensis Flea Frog; Razinha-Pulga Teresensis <https://amphibiaweb.org/species/8211> 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.

AmphibiaWeb's policy on data use.