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Article
Published: 2021-12-13

A new species of red toad, Schismaderma Smith, 1849 (Anura: Bufonidae), from central Angola

CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado, Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, Portugal. Departamento de Biologia, Faculdade de Ciências, Universidade do Porto, 4169-007 Porto, Portugal
CIBIO-InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado, Universidade do Porto, Campus Agrário de Vairão, Rua Padre Armando Quintas, 4485-661 Vairão, Portugal. Fundação Kissama, Luanda, Angola
Zoology and Entomology Molecular Lab, Department of Zoology and Entomology, Rhodes University, Makhanda, South Africa 8South African Institute for Aquatic Biodiversity (SAIAB), Makhanda, South Africa
Zoology and Entomology Molecular Lab, Department of Zoology and Entomology, Rhodes University, Makhanda, South Africa
Museum für Naturkunde—Leibniz Institute for Evolution and Biodiversity Science, Invalidenstr. 43, 10115 Berlin, Germany. Berlin-Brandenburg Institute of Advanced Biodiversity Research—BBIB, Altensteinstr. 34, 14195 Berlin, Germany
South African Institute for Aquatic Biodiversity (SAIAB), Makhanda, South Africa
Amphibia allopatric speciation cryptic diversity endemism integrative taxonomy Angolan Miombo woodlands

Abstract

A new species of red toad, from the previously monotypic genus Schismaderma, is described. The new species was found in Malanje Province, and seems endemic to central Angola, occurring approximately 500 km west of the closest known records of Schismaderma carens. Unusual adult colouration and geographical distance to remaining S. carens populations suggested specific differentiation. In an integrative approach, we compared the red toads from central Angola with S. carens from across the entire range, including molecular data, morphology of adults and tadpoles, and male advertisement calls. Phylogenetic analysis based on mitochondrial (12S, 16S, COI) and nuclear (CXCR4, RAG1) markers, retrieved the Angolan clade as monophyletic, and revealed intra-specific substructuring among the remaining Schismaderma. Genetic distances supported specific differentiation of the central Angolan material compared with other S. carens. Adults from the new Angolan species have bolder ventral patterning and smaller body size than S. carens. No obvious differences were detected between the tadpoles and the advertisement calls of the two Schismaderma species. This discovery adds to the knowledge of the herpetofauna of the Angolan Miombo woodlands, a poorly understood ecoregion, and likely more biodiverse than previously assumed. The result of past river basin dynamics in central Angola likely led to the evolution of this new species of Schismaderma.

 

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