The four-digit toad or dwarf toad (''Didynamipus sjostedti'') is a species of

toad Toad is a common name for certain frogs, especially of the family Bufonidae, that are characterized by dry, leathery skin, short legs, and large bumps covering the parotoid glands. A distinction between frogs and toads is not made in scient ...

in the family

Bufonidae {{Cat main, Toad This category contains both species commonly called toads, and the true toads from the family Bufonidae. Animals by common name Frogs ...

. It is found in

Bioko Bioko (; historically Fernando Po; bvb, Ëtulá Ëria) is an island off the west coast of Africa and the northernmost part of Equatorial Guinea. Its population was 335,048 at the 2015 census and it covers an area of . The island is located of ...

(Equatorial Guinea), southwestern Cameroon, and southeastern Nigeria. It is the only species in the genus ''Didynamipus''.

Etymology

The specific name ''sjostedti'' honours Bror Yngve Sjöstedt, a Swedish entomologist and ornithologist who collected the

type series In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes the ...

Description

''Didynamipus sjostedti'' are very small toads: males grow to and females to in

snout–vent length Snout–vent length (SVL) is a morphometric measurement taken in herpetology from the tip of the snout to the most posterior opening of the cloacal slit (vent)."direct line distance from tip of snout to posterior margin of vent" It is the mos ...

. The snout is sharp in males but rounded in females; males also have a ridge on the top the snout that gives it an upturned appearance. The tympanum is absent. The hands and feet are reduced, with the two outer fingers and toes and the innermost toes present only as tubercles. No webbing is present. The dorsum is brown with lighter and darker mottling.

Habitat and conservation

''Didynamipus sjostedti'' occur on forest edges and in clearings in moist forest at elevations of

above sea level Height above mean sea level is a measure of the vertical distance (height, elevation or altitude) of a location in reference to a historic mean sea level taken as a vertical datum. In geodesy, it is formalized as '' orthometric heights''. The ...

, often in mixed-sex and mixed-lifestage aggregations. They can occur both in leaf litter and perched atop low vegetation. Individuals found near terretrial egg masses suggest terrestrial breeding and direct development (i.e., there is no free-living larval stage). This species appears to tolerate some habitat modification and has also been found in secondary forest and farmland, although it is still considered threatened by habitat loss primarily caused by agricultural expansion. It is known from inside or near several protected areas.

References

{{Taxonbar, from=Q10755439, from2=Q2670468 Didynamipus Frogs of Africa Amphibians of West Africa Amphibians of Cameroon Amphibians of Equatorial Guinea Fauna of Nigeria Amphibians described in 1903 Taxa named by Lars Gabriel Andersson Taxonomy articles created by Polbot