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Issue: Vol. 5759 No. 4: 18 Feb. 2026
Type: Article
Published: 2026-02-18
DOI: 10.11646/zootaxa.5759.4.5
Page range: 453-463
Abstract views: 91
PDF downloaded: 19

Description of Mesoaphyosemion izyarae (Cyprinodontiformes: Nothobranchiidae), a new killifish species from southern Equatorial Guinea

Zoologisches Forschungsmuseum Alexander Koenig; Department of Vertebrates; Adenauerallee 160; D–53113 Bonn; Germany; Max-Planck-Institut für Evolutionsbiologie; Department of Evolutionary Genetics; August-Thienemann-Strasse 2; D–24306 Plön; Germany
Waidmannweg 98; D-41239 Mönchengladbach; Germany
Arturo Soria 192 2D; 28043 Madrid; Spain
Alhaurín 4-2G; 28042- Madrid; Spain
Clara Campoamor 50; 28420; Madrid; Spain
Royal Museum for Central Africa; Vertebrate Section; Ichthyology; Leuvensesteenweg13; B-3080 Tervuren; Belgium
Pisces phylogeny colour pattern taxonomy mtDNA Rio Mitemele Pleistocene rainforest refuge

Abstract

Mesoaphyosemion izyarae sp. nov., is described from a small left-bank tributary of the Mitemele River in southern Equatorial Guinea. The new species is distinguished from all other described Mesoaphyosemion species by a unique combination of male colouration characters: dorsal fin yellow with red streaks between fin rays; anal and pelvic fins yellow with black or dark red margin, basally light blue, caudal fin in centre black with red streaks between fin rays, broad yellow area on dorsal and ventral margin, body metallic light blue with more or regular rows of red dots on side, posteriorly denser and forming a reticulated pattern. The species status is supported by mtDNA analyses, including nine of the eleven described valid Mesoaphyosemion species.

 

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How to Cite

Sonnenberg, R., Ott, H., Rodriguez, A.G., Olias, C.V., Martinez, F.P. & Zee, J.R.V.D. (2026) Description of Mesoaphyosemion izyarae (Cyprinodontiformes: Nothobranchiidae), a new killifish species from southern Equatorial Guinea. Zootaxa, 5759 (4), 453–463. https://doi.org/10.11646/zootaxa.5759.4.5