All Mexican freshwater fish

Xiphophorus birchmanni (Lechner & Radda, 1987) — by Juan Miguel Artigas Azas

A widespread species, yet vulnerable to local pressures reshaping its habitat and genetic integrity.

Priapella olmecae Meyer & Espinoza-Pérez, 1990 — by Juan Miguel Artigas Azas

Priapella olmecae is a livebearer from Veracruz whose survival is threatened by habitat degradation.

Xiphophorus cortezi (Rosen, 1960) — by Juan Miguel Artigas Azas

One of the easiest swordtail species native to the Pánuco drainage to keep in captivity.

Xiphophorus montezumae Jordan & Snyder, 1899 — by Juan Miguel Artigas Azas

Xiphophorus montezumae was initially believed to have a much wider distribution than is recognized today.

Xiphophorus nigrensis (Rosen, 1960) — by Juan Miguel Artigas Azas

A polymorphic species with three different morphs of males.

Return policy for our books and digital documents — by Juan Miguel Artigas Azas

This policy outlines our commitment to customer satisfaction through clear refund and replacement terms. For digital products (PDFs), refunds are generally not offered due to the nature of the item, but replacements are provided if the file is corrupted, incomplete, or incorrect. Physical books are shipped with tracking, and any items damaged upon arrival will be replaced free of charge upon prompt notification with supporting evidence. All claims should be made within a reasonable timeframe, and replacements are limited to the originally purchased item. While shipping delays are beyond our control, we strive to assist with any delivery issues.

Subscriptions to the Freshwater Fishes of Mexico using PayPal — by Juan Miguel Artigas Azas

Freshwater Fishes of Mexico offers subscriptions to people, which are administered by PayPal. The way they operate and how to cancel the renewals service are explained in this small document.

Our citation standards — by Juan Miguel Artigas Azas

The standard used in the Freshwater Fishes of Mexico for citation of published works.