Discoglossus scovazzi Camerano, 1878
Original Published Description:
Discoglossus scovazzi is distributed in northwest Africa and the extreme southwest of Europe on the Iberian peninsula, having an evolutionary past where the species population was split by the formation of the Strait of Gibraltar.
D. scovazzi is found in the western Mediterranean zone, chiefly in the Mediterranean forests and woodland ecoregion (World Wildlife Fund & Hogan, 2007), including portions of northern Morocco and much of southwest Iberia, including Ceuta and Melilla in Spain. Occurrence in western Algeria is possible, but field confirmation of this anuran in that country is needed. The taxon is known to be present in altitudes up to 2600 meters in the High Atlas Mountains of Morocco (Salvador et al. 2009).
D. scovazzi has been removed from the synonymy of D. pictus (García-París & Jockusch, 1999).
D. scovazzi manifests a pointed snout and round eye pupils. Subarticular tubercles are lacking, and the tympanum is inconspicuous. Dorsum exhibits a dorsolateral fold on each side, usually extending only from eye to shoulder. Dorsal skin shows irregular dark spots or longitudinal stripes (Salvador, 1996).
Habitat and Ecology
The species is associated with streams, cisterns and pools of either fresh or saline water. It breeds in such wetland habitats; females lay a maximum of 1000 eggs at one time. Terrestrial habitats of the species include oak forests, Nerium oleander scrub and archaeological ruins (Salvador et al. 2009). D. scovazzi is chiefly found in Mediterranean woodlands and forests (World Wildlife Fund & Hogan, 2007). Individuals can often be discovered hiding under rocks, in crevices and even under the bark of cork oaks (Quercus suber). It is thought that the species can endure some relatively minor habitat modification.
D. scovazzi is considered common in its Moroccan range, particularally in sub humid and humid areas, where surface waters are more evident (Salvador et al. 2009). However, increasing pressure on agricultural land conversion and from surface water extraction to serve the expanding regional human population is placing downward pressure on this species as well as all amphibians in the region (World Wildlife Fund & Hogan, 2007).
Evolution and Systematics
The phylogenetics of D. scovazzi are clearly related to the vicariance created by the Strait of Gibraltar and the geological formation of that geographic feature. Morphology and DNA of D. scovazzi have been compared with D. jeanneae. Individuals of the D. scovazzi populations of North Africa and southwest Iberia were sampled and contrasted with sampling of D. jeanneae from eastern Iberia. Morphologies of these two related taxa were differentiated using Mahalanobis distance metrics. Results showed that the effective Mahalanobis distance was greater for the intercontinental than the intracontinental populations by a factor of 2.3 to 3.3. Thus the geographic barrier of the Strait of Gibraltar has had a strong effect on the morphological differentiation as well as the genetic differentiation of the two taxa. Furthermore, mitochondrial DNA and allozyme differentiation is substantial, suggesting the species separation between D. scovazzi and D. jeanneae precedes or is coincident with the formation of the Strait of Gibraltar (Busack & Lawson, 2008).
IUCN Red List Category and Justification of Conservation Status
D. scovazzi is listed as Least Concern (ver 3.1) in view of its rather broad distribution, presumed large population, and because it is unlikely to be declining fast enough to qualify for listing in a more threatened category (Salvador et al. 2009).
D. scovazzi is threatened chiefly by localized loss of breeding sites through agricultural development and increased salinisation in coastal lagoons (Salvador et al. 2009). The primary driver to species threats is the burgeoning human population within the species range, which population explosion has principally erupted since about 1960; furthermore, the range of D. scovazzi in Morocco coincides with the portion of Morocco that has the greatest agricultural potential, based upon edaphic and rainfall factors. Thus the pressure on overgrazing, deforestation, conversion of habitat to cropland and over-extraction of surface waters is great in this portion of Morocco (World Wildlife Fund & Hogan, 2007).
Conservation Actions and Management
D. scovazzi is listed on Appendix III of the Bern Convention; moreover, the species occurs in some protected areas (Salvador et al. 2009).
- Discoglossus pictus scovazzi — Lanza, Nascetti, Capula, and Bullini, 1986 (synonym)
- Discoglossus scovazzi — Martínez-Solano, 2004 (synonym)