" Xiphophorus kosszanderi n. sp., from the Arroyo Chapultepec, Nuevo Leon, Mexico is described: deep bodied, rounded head, dark black spot at the basis of the anal fin; adult male whith a short black sword-like caudal appendage; deep lying dots at the body sides; claw wanting at tip of ray 5a of gonopodium; distal serrae on ray 4p well developed; blade on ray 3 long and slender; micromelanophore tail pattern in both sexes; body form, coloration. sexual dimorphism and gonopodial characters are illustrated. - X. kosszanderi n. sp. shows features of xiphidium (Gordon 1932) couchianus (GIRARD 1859) and variatus (MEEK 1904).
Xiphophorus roseni n. sp. from the same type locality (see kosszanderi) is described: long head, slender bodied, dark black spot at the basis of the anal fin, micromelanophore tail patterns; adult male with a relatively high dorsal fin; species with a well-developed reticular network both above and below midlateral scale row, two zigzag midlateral dark stripes; body form, coloration, sexual dimorphism and gonopodial characters are illustrated. - X. roseni n. sp. differs by the combination of distict characters from all the other species of the genus known so far. The new species shows features of variatus (MEEK 1904) andersi MEYER & SCHARTL 1980 milleri ROSEN 1960 and maculatus (GUNTHER 1866) "
Classification: Taxonomy and phylogeny.
Reference in bibliography for species (2)
Meyer, Manfred & L. Wischnath. 1981. "Zwei neue Xiphophorus-Arten aus Nuevo Leon, Mexiko (Pisces: Poeciliidae)". Aquaria: Vivaristische Fachzeitschrift für die Schweiz und Österreich. 28(8): 129-134 (ffm00068) (abstract)