Xiphophorus multilineatus

Xiphophorus multilineatus Rauchenberger, Kallman & Morizot, 1990

Affiliation: northern swordtail

IUCN status: data deficient

Distribution: Río Coy, Tambaque and Oxitipa in the Río Pánuco drainage, San Luis Potosí, Mexico

Known locations (existing/former): at least 3

Type locality: Río Coy near its confluence with Río Tampaón, Río Pánuco drainage, San Luis Potosí, Mexico

(17.2.1979, K. D. Kallman, D. C. Morizot, V. Borkoski & G. Peters)

Habitat description: Thrives in clear, swiftly flowing streams with a moderate to high flow. The substrate in these habitats is soft (mud or fine sand). Lots of wood is present with patches of submerged plants or their roots. The water is well-oxygenated, with cool temperatures that support the species’ health and reproductive success.

Biotope reports:

• none yet

Description: Small to medium-sized livebearer, with males reaching up to 2,5 to 4,5 cm in total length and females up to 4 cm. Males exhibit a high-backed, slender body with a prominent, elongated sword in the caudal fin with black pigmentation along the edges (lower or both). The body colour is typically a pale metallic blue with multiple vertical stripes along the flanks. Females are larger and lack the sword but possess the same metallic coloration with a subtle horizontal stripe. Some individuals exhibit a faint black line running from the eye to the lips.

Variability: Very variable species. Multiple male types exist (with different size and colour). Smaller males, typically measuring up to 3 cm, often resemble females in colouration, but they can be also yellow or blue. In contrast, larger males, reaching up to 5 cm in length, display significantly more intense colouration, usually with a striking blue tint. However, there are also large males with a female-like colouration and bright yellow sword. Temporary changes in colouration also reflect current mood and position in the hierarchy.

XWG status: not yet actively managed

Represented in aquaria: Xiphophorus multilineatus is rare in the aquarium trade and is typically kept by specialized enthusiasts who can provide the specific environmental conditions required for the species’ survival.

Known issues: This is a shy species, often hiding among aquatic plants and seeking shelter from bright lighting or disturbance. In aquarium, it is important to provide ample hiding spaces and ensure that the water quality remains stable.

Known collections or populations:

• Arroyo Tambaque (and Río Tambaque), San Luis Potosí, Mexico
• Río Coy, San Luis Potosí, Mexico

(if you have more information, please contact us at info@xipho.org – thanks!)