Ptychadena schillukorum (Werner, 1908)
Original Published Description:
Sudan Grassland Frog (English), Schilluk Ridged Frog (English)
Ptychadena schillukorum is a medium sized anuran found across a wide swath of the African Sahel from Senegal to Sudan, and extending southward into parts of east Africa; the species chiefly occurs in arid and semi-arid savanna, especially in the broad West Sudanian savanna ecoregion. A distinctive dark interorbital V-shape is present in adults.
Ptychadena schillukorum has been recorded in Benin, Burkina Faso, Cameroon, Egypt, Ethiopia, Ghana, Kenya, Malawi, Mozambique, Namibia, Senegal, Somalia, South Africa, Sudan and Tanzania (Rödel, 2000). A key element of its range is a large swath across the Sahel designated as the West Sudanian savanna ecoregion, where it is found in areas that have access to surface water such as the vast Niger River Basin (Hogan, 2013).
P. schillukorum is a medium-sized, compact ranid with comparatively short and massive hind legs. The snout to vent length of males is approximately 43 to 48 millimetres (mm), with females attaining a corresponding measurement of 43 to 49 mm (Rödel, 2000).
The somewhat discontinuous dorsal ridges of P. schillukorum are black. The light-colored remains of the dorsolateral ridges have fine black borders. A black patch marks the eyelids. A dark V-shape is present between the eyes. The anterior border of the vocal sac and the canthal area are both somewhat darker, and the upper lip is light coloured, evincing no markings. This white colour extends to the upper arm where an isolated white bulge is found. The arms are faintly mottled. Black bars are present on the legs: three bars usually appear on the thighs, and three to four bars on the shanks. These bars are frequently paler centrally. The outer part of the thigh is speckled, adorned with irregular light lines or else densely spotted with black. The lower jaw is either faintly spotted or mottled. The throat is mottled or shows no coloration at all. The underside of the foot is dark, and the webbing is slightly pigmented dark. The remainder of the venter is a uniform whitish (Rödel, 2000).
Habitat and Ecology
P. schillukorum is typically found on the banks of rivers and lakes. In much of the Sahel it occurs in the West Sudanian savanna ecoregion, an arid to semi-arid environment; more specifically, the species is characteristically seen in the vicinity of the Sahelian river systems such as the Niger Basin (Hogan, 2013) P. schillukorum prey chiefly consist of moderately large active terrestrial animals, i.e. orthopterans, spiders and cockroaches. The diet does not appear to have significant seasonal variation (Rödel, 2000).
P. schillukorum has a call that endures approximately 0.36 to 0.40 seconds, with a dominant frequency of three to four kilohertz. The call consists of six or seven notes consisting of five or six pulses (Rödel, 2000).
In Burkino Faso and Nigeria, P. schillukorum is is one of many frog species that are traded or consumed as a source of animal protein. Frogs are an integral part of the economy in areas with large frog populations because villagers are employed to catch and prepare frogs, and they are an "important international trading item." Aside from their value as an essential food source, they may also be used for cultural reasons and as traditional medicine in areas where Western medicine is not available (Mohneke, 2010).
- Rana schillukorum Werner, 1908 "1907" (synonym)
- Rana floweri Boulenger, 1917 (synonym)
- Rana (Ptychadena) floweri — De Witte, 1921 (synonym)
- Rana mascareniensis schillukorum — Ahl, 1924 (synonym)
- Rana (Hildebrandtia) barbouri Loveridge, 1925 (synonym)
- Abrana floweri — Parker, 1931 "1930" (synonym)
- Abrana cotti Parker, 1931 "1930" (synonym)
- Rana (Abrana) floweri — Loveridge, 1933 (synonym)
- Ptychadena frontalis Laurent, 1954 (synonym)
- Rana (Ptychadena) frontalis — Schmidt and Inger, 1959 (synonym)
- Ptychadena floweri — Poynton, 1964 (synonym)
- Rana (Parkerana) cotti — Dubois, 1984 (synonym)
- Rana (Parkerana) floweri — Dubois, 1984 (synonym)
- Ptychadena (Parkerana) floweri — Dubois, 1984 (synonym)
- Ptychadena cotti — Poynton and Broadley, 1985 (synonym)
- Ptychadena schillukorum — Dubois, 1987 "1986" (synonym)
- Ptychadena (Parkerana) cotti — Dubois, 1992 (synonym)
- Ptychadena (Ptychadena) schillukorum — Dubois, 1992 (synonym)