Synopsis of the Amphibians of Equatorial Guinea based upon the Authors’ Field Work and Spanish Natural History Collections Author Sánchez-Vialas, Alberto Museo Nacional de Ciencias Naturales (MNCN-CSIC), C / José Gutiérrez Abascal, 2. 28006, Madrid, Spain; Author Calvo-Revuelta, Marta Museo Nacional de Ciencias Naturales (MNCN-CSIC), C / José Gutiérrez Abascal, 2. 28006, Madrid, Spain; Author Castroviejo-Fisher, Santiago Laboratorio de Sistemática de Vertebrados, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS). Av / Ipiranga, 6681, Prédio 40, sala 110, 90619 - 900, Porto Alegre, Brazil; * Corresponding author: IDlR (iriva @ mncn. csic. es) Author De, Ignacio Museo Nacional de Ciencias Naturales (MNCN-CSIC), C / José Gutiérrez Abascal, 2. 28006, Madrid, Spain; text Proceedings of the California Academy of Sciences 2020 2020-03-31 66 8 137 230 journal article 295393 10.5281/zenodo.11105986 4c7b4d3d-1fbe-4f48-8cb2-002e928eae42 0068-547X 11105986 Cardioglossa leucomystax ( Boulenger, 1903 ) Photo figures 5D–E TYPE LOCALITY .— “Cap Saint Jean, Guinée espagnole”, Cabo San Juan, Río Muni, Equatorial Guinea . DISTRIBUTION .— This species has the largest geographic range in the genus, occuring from Nigeria to Gabon , and throughout Central African Republic , Democratic Republic of Congo and Republic of Congo . Within Equatorial Guinea , it has been recorded from Río Muni only, in Cabo San Juan ( Boulenger 1903 ) and in Monte Alén National Park ( De la Riva 1994 ). Here we present the first records of C. leucomystax for Bioko, and also an additional locality for Río Muni ( Map 5A ). COMMENTS .— The newly recorded populations from Bioko are closely related to the ones from Cameroon (authors’ unpublished data). SPECIMENS EXAMINED .— Seven specimens . Niefang , Alosa , 14 August 1985 ( EBD 34220 ) ; River mouth of Moaba , Bioko , 03°14ʹ01.41ʺN , 08°37ʹ19.64ʺE , 21 November 2003 ( MNCN 48923–48925 ) ; Río Ole , on the way to Caldera de Luba , Bioko , 03°15ʹ55.40ʺN , 08°28ʹ31.64ʺE , 26 November 2003 ( MNCN 48926–48927 ) ; between Río Ole and Casa Moraca , Bioko , 03°15ʹ33.05ʺN , 08°29ʹ11.18ʺE , 29 November 2003 ( MNCN 48928 ) .