Fletcher's frog

Species of amphibian

Fletcher's frog (Platyplectrum fletcheri), commonly known as the sandpaper frog or black soled frog, is a species of nocturnal, terrestrial frog native to eastern Australia. It is primarily found in wet sclerophyll forests along mountain ranges and the coast. The Fletcher's frog's breeding behavior revolves around ephemeral water bodies created by rainfall. Male frogs compete with one another over territories that contain these pools, while female frogs choose desirable males to mate with. Female frogs produce foam and lay their eggs within the frothy mass. The nest's mucus has protective properties that enhance the survival odds of the progeny.

Fletcher's frog was classified in the former genus Lechriodus until its synonymization with Platyplectrum in 2021. Prior to its merging, Lechriodus was one of three subfamilies of Leptodactylidae present in New Guinea and Australia. Three other species in the former Lechriodus genus are Platyplectrum aganoposis, Platyplectrum melanopyga, and Platyplectrum platyceps.

Fletcher's frog resides in the temperate rainforest along the southeast coast of Australia, preferring a habitat with high rainfall and deep soil. This frog actively seeks areas with mid slopes or plateaux. The environment provided by these geographical conditions fosters an abundance of ephemeral water bodies, a feature essential to Fletcher's frog's breeding success. There have been several confirmed sightings of the species in the 800 mile region between Ourimbah, New South Wales, and southeastern Queensland.

Considered a medium sized anuran, Fletcher's frog is approximately 4–5 centimeters in length. It has a reddish brown to black colored back and a white colored stomach. Although its stomach is smooth in texture, the back of Fletcher's frog is granular and contains multiple ridges. The limbs have dark colored crossbands. One shaded narrow stripe runs between the frog's eyes. There is an additional band that starts at the nostril, extends through the eye, curves around the tympanum, and ends at the shoulder. The frog's pupil is horizontal, and the iris is golden in color. Fingers and toes show traces of webbing. The hands of Fletcher's frog consist of four fingers. In both hands, the lateral side of the inner finger had nuptial pads. Unlike female frogs, male frogs have a small, raised nub on their inner finger. Moreover, male fingers are shorter and thinner compared to those of females. There is only a small degree of sexual dimorphism within the species. Females are approximately 6% larger than males, a relatively small difference compared to other amphibians where females are up to 20% larger than males. Some other species that resemble Fletcher's frog are Mixophyes balbus, Mixophyes fasciolatus, Mixophyes fleayi, and Mixophyes iteratus; however, Fletcher's frog is generally smaller in size. Moreover, it has horizontal pupils instead of the vertical pupils found in the Mixophyes genus. Feltcher's frog tadpoles are cannibalistic, actively preying on conspecific eggs by removing sections of oviduct fluid from the froth nests and consuming them whole. Tadpoles remain near the spawn for extended periods of time, feeding continuously until their entire abdomen is filled. Due to the environmental and competitive pressures of living in temporary water bodies where vegetable food is scarce, tadpoles appear to be habitually carnivorous and cannibalistic. When raised in laboratory conditions, tadpoles fed on Spirulina algae when it was added to their environment; however, they quickly showed a preference for conspecific eggs when it was added to their container.

The Fletcher's frog's development is very rapid. Tadpoles hatch from their eggs after 3 to 4 days, and metamorphism occurs after 20 to 30 days.

Fletcher's frog is listed by the International Union for Conservation of Nature Red List of Threatened Species (IUCN Red List) as Least Concerned in 2004 due to its abundance in suitable habitats; however, the IUCN Red List acknowledges that the status to be updated to reflect the current population demographic. The exploitation of wet sclerophyll forests and continued forest logging has reduced this species' natural habitat dramatically, presenting a significant threat to this species.