After Sr José Alvarez del Villar the then Secretario de Marina in Mexico. He passed on specimens of this sp. to Rosen for identification.
Commonly referred to as the Upland Swordtail.

Donn E. Rosen 1960.

Middle-American poeciliid fishes of the genus Xiphophorus.
Bull. Fla. St. Mus. Biol. Sci 5 (4): p 57-242.

Male 60 mm; female 75 mm.

Member of the group comprising alvarezi, birchmanni, continens, cortezi, helleri, malinche, montezumae, multilineatus, nezahualcoyotl, nigrensis, pygmaeus & signum.

• Xiphophorus helleri alvarezi Rosen 1960

Populations

• Coban Yellow.
• Yellow. Seen on an American list. May be the Coban form.
• Rio Dolores, Guatemala. I had females only from Austria in 2004 which dropped a few broods. An American form called 'Delores strain' may be from the same stock

Rio Santo Domingo, a tributary of the Rio Jatate in the upper reaches of the Rio Usumacinta drainage, Chiapas, Mexico.
Type specimens were collected by M. del Toro, August 1948 90 km east of Comitán. This location is reportedly 500 m above sea level.
Holotype measured 39 mm sl (male); allotype 39·4 mmsl (female).

Upland drainage of the Chiapas Sierras. In Guatemala; Huehuetenango, El Quiche & Alta Verapaz in the Rio Usumacinta drainage.

Collected in rivers with a good flow & plenty of plant growth.

I have bred Rio Dolores & Coban populations. The Rio Dolores female was received as a lone female & was put in a 15" square tank with plants & mops as cover. Young were dropped & didn't seem to come to any harm. These were transferred later to their own tank.
The Coban population were a pair in the same set up. Again they did not seem to molest the young which were again transferred at a later date.

This sp. is reportedly shy & likes to hide at the back of the tank. I can confirm that the above populations also exhibit this trait.
Reports seem to suggest that this sp. is not suited to colony breeding.