Description
Rhinella lilyrodriguezae is a large toad from the Rhinella festae species group, which was described from four adult females and two unsexed juveniles. The females have a snout-vent length range of 47.1 - 58.3 mm. The head is wider than long, but narrower than the body. In the dorsal view, the head is triangular with a long, acuminate, pointed, or rounded snout that protrudes over the lower jaw and has a slight antroventral angle. On the ventral side there is a keel on the snout. The small, round nostrils do not protrude, are directed laterally, and position near the anterior margin of the lower jaw. The area between the nostrils is concave. The distance from the tip of the snout to the nostrils is shorter than the distance from the nostrils to the eyes. In the profile, the canthus rostralis is angular and rounded, and continues along the head to above the eye, extending into the supratympanic crest. The loreal region is concave. The interorbital distance is twice the eye diameter. The upper eyelid has many low, keratin-tipped tubercles. The tympanum has a superficial membrane and a weakly defined annulus with a diameter that is smaller than the eye. The tympanum is isolated from the parotoid glands and post-orbital crest. The triangular parotoid glands are moderately large, about the same size as the eye diameter, and incorporated into a lateral row of tubercles that extended to the groin. The head has many crests, including the distinct orbital crest that begin as the canthus rostralis then runs above the eye and continue behind the eye as a the laterally expanded supratympanic crest. There are also moderately-developed cephalic crests. However there are no occiptial crests. The dorsal and lateral skin on the head has many warts. The skin on the rest of the dorsum has scattered conical tubercles with keratinized tips on otherwise smooth skin. The cloaca is positioned at the mid-level of the thighs and the opening is directed posteriorly. There is no cloacal sheath and the posterior half is free. The flanks have fewer tubercles. There is no dorsolateral fold. The skin on the throat, chest, and belly is granular. The dorsal skin on the forelimbs has densely scattered subconical tubercles. The forearm is long and slender, about a quarter of the snout-vent length. The hand is longer than the forearm. The distinct, round palmer tubercle is twice the size of the oval thenar tubercle. The palms also have indistinct, low supernumary tubercles. The long fingers have a relative length of I < II < IV < III and have basal webbing between fingers II - IV. Finger IV has well-defined lateral fringes. The tips of the fingers are rounded. The diffuse subarticular tubercles are low and round to oval in shape. The hind limbs are also long, slender, and have a spiculated dorsal surface like the forelimbs. The tibia is about 40% of the snout-vent length and is slightly longer than the foot. The foot does not have a tarsal fold but does have a large, elliptical inner metatarsal tubercle that is weakly protuberant and a smaller, round outer metatarsal tubercle that is half the size of the inner metatarsal tubercle. The feet also have indistinct supernumerary tubercles. The long toes have relative lengths of I < II < III < V < IV. They also have moderate webbing with a formula of I 1 – 2^- II 1^- – 2 III 1 – 3⁺ IV 3⁺ – 2 V, and all unwebbed portions have well-defined lateral fringes. The subarticular tubercles of the toes are similar to those found on the fingers: diffuse, low, and round to oval. The tips of the toes are also rounded (Cusi et al. 2017).

Rhinella lilyrodriguezae is physically similar to R. lindae, R. tenrec, and R. truebae, which are members of the R. acrolopha species group, in terms of size. But the species can be differentiated based on geography (the latter three are found in Colombia, and Panama), and by R. lilyrodriguezae having moderately developed cranial crests but lacking occiptal crests, an anteroventrally directed snout, a weak tympanic membrane, a dorsolateral row of small conical tubercles that connects the parotoid gland to the groin, basal webbing on the hands, and moderate webbing on the feet. Of the other Peruvian members of the R. festae species group (R. chavin, R. manu, R. nesiotes and R. yanachaga), which R. lilyrodriguezae is a member, most of the females are smaller than R. lilyrodriguezae, except R. chavin. Rhinella chavin can be differentiated by it having a rounded snout, relatively larger parotoid glands, glands on the limbs, and its dorsolateral row of tubercles only extending from the forearm insertion to the inguinal region. For all other comparisons, please see the citation (Cusi et al. 2017).

In life, the dorsum coloration varies based on time of day, with it being lighter at night than during the day. However it generally ranges from light brown to greenish brown and has irregular brown, dark brown or black markings. It may also have a grey white middorsal stripe. The flanks have irregular, dark green dorsolateral blotches that begin behind the parotoid glands and extend to the sacral region. The dorsolateral row of tubercles are dark brown. The chest, belly, and ventral thighs, are cream yellow to brownish grey, and has tiny light cream spots. The posterior region of the belly is cream yellow. The iris is silvery greenish with irregular black mottling (Cusi et al. 2017).

In preservative, the dorsum is light brown with irregular dark brown spots and markings on the dorsum and hind limbs. There are also dark gray transverse bands on the shanks. The flanks are cream colored and are marked with a well-defined, discontinuous, broad, black ventrolateral band that begins at the brown tympanum and ends in the inguinal region. The dorsolateral row of tubercles is reddish brown. The upper lip is cream colored and lacks bands or spots. The throat, chest, and belly become gray, but the minute light cream spots retain their coloration. The ventral surfaces of the thigh are the same as the ventral body. The palms and planters become dark gray while the subarticular tubercles become cream (Cusi et al. 2017).

There is considerable color variation within the same individual based on time of day, with the species being lighter at night than during the day. Between individuals, they may or may not have mid-dorsal stripes, and the "sharpness" of the snout may vary. Sexual dimorphism is unknown as no male specimens were found at the time of the species description. Developmentally, juveniles have more prominent cranial crests than adults (Cusi et al. 2017).

Distribution and Habitat

Country distribution from AmphibiaWeb's database: Peru

View distribution map in BerkeleyMapper.

Known only from the type localities in montane forests of the Cordillera Azul National Park, Alto Biavo district, in northern Peru, between 1,245 and 1,280 m in elevation (Cusi et al. 2017).

Life History, Abundance, Activity, and Special Behaviors
Rhinella lilyrodriguezae females were found during the dry season. The specimens were nocturnal and semiarboreal with all being found between 20:33 and 22:49 hours on bushes that were 10 - 100 cm from the ground (Cusi et al. 2017).

One gravid female was had 185 ovarian eggs with diameters between 3.2 - 2.7 mm. The eggs were pale cream yellow in preservative (Cusi et al. 2017).

Rhinella lilyrodriguezae can be found in sympatry with Pristimantis peruvianus, P. ventrimarmoratus, Osteocephalus mimeticus, and what are assumed to be Hyloscirtus phyllognathus, and Rulyrana flavopunctata (Cusi et al. 2017).

Trends and Threats
The area in which R. lilyrodriguezae is found has been impacted by logging, soil removal, and noise pollution. Subsistence game hunting and fishing by locals is also known in this area. However, at the time of the species description, the species had a recommended IUCN listing of "Data Deficient" (Cusi et al. 2017).

Possible reasons for amphibian decline

General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Local pesticides, fertilizers, and pollutants
Intentional mortality (over-harvesting, pet trade or collecting)

Comments
Bayesian Inference and Maximum Likelihood analyses of 16S rRNA found that R. lilyrodriguezae is sister to the clade composed of R. chavin and R. yanachaga (Cusi et al. 2017).

This species was featured in News of the Week 7 October 2024:

We have known for decades now that the global protected area network leaves more amphibian species unprotected than it does for other terrestrial vertebrate classes. Given commitments by many countries to protect 30% of the earth by 2030, how might new protected areas (PAs) shore up these gaps? Steigerwald et al. 2024 used compiled range maps for terrestrial vertebrates and the World Database of Protected Areas to explore the amphibian conservation potential of microreserves (<10 km²), whose value is often discounted when considering more common conservation targets like mammal and bird species. They report the same proportion of unprotected amphibians as a comparable analysis 19 years ago, but that the rate of establishment of new amphibian-containing PAs has declined since the early 2000s. They also find that amphibian ranges are on average smaller than other terrestrial vertebrates, such that targeted microreserves could protect most of the range of many amphibian species—particularly threatened ones. Importantly, they find that microreserves increase the PA network’s coverage of amphibian diversity faster than larger PAs. This study demonstrates what we could gain by valuing targeted microreserves as a critically important conservation tool for underrepresented taxa. (Written by Emma Steigerwald)

References
Cusi, J.C., Moravec, J., Lehr, E., and Gvoždík, V. (2017). A new species of semiarboreal toad of the Rhinella festae group (Anura, Bufonidae) from the Cordillera Azul National Park, Peru. ZooKeys 673, 21-47. [link]

Steigerwald, E., Chen, J., Oshiro, J. Vredenburg, V.T., Catenazzi, A., and Koo, M. (2024). Microreserves are an important tool for amphibian conservation. Communications Biology 7, 1177. [link]

Species Account Citation: AmphibiaWeb 2024 Rhinella lilyrodriguezae: Lily Rodriguez's Beaked Toad (English) <https://amphibiaweb.org/species/8623> University of California, Berkeley, CA, USA. Accessed Nov 27, 2024.

Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 27 Nov 2024.

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