Rio Grande Cichlid

Rio Grande Cichlid, Herichthys cyanoguttatus

Rio Grande Cichlid, Herichthys cyanoguttatus. Fish caught from brackish waters within Coral Reef Park, Palmetto Bay, Florida, February 2020. Length: 13 cm (5.1 inches). Catch, photograph, and identification courtesy of Josh Leisen (joshadventures.com), Gaylord, Michigan.

Rio Grande Cichlid, Herichthys cyanoguttatus. Fish caught from the drainage canals in Tampa, Florida, May 2018. Length: 15 cm (5.9 inches). Catch, photograph and identification courtesy of Ben Cantrell, San Diego, California.

Rio Grande Cichlid, Herichthys cyanoguttatus. Fish caught from the Gila River, Phoenix, Arizona, July 2017. Length: 15 cm (5.9 inches). Catch, photograph and identification courtesy of Ben Cantrell, San Diego, California.

Rio Grande Cichlid, Herichthys cyanoguttatus. Fish caught from the Gila River, Phoenix, Arizona, July 2017. Length: 15 cm (5.9 inches). atch, photographs and identifications courtesy of Ben Cantrell, San Diego, California.

Rio Grande Cichlid, Herichthys cyanoguttatus. Fish caught from the Colorado River, Austin, Texas, August 2018. Length: 26 cm (10 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.

The Rio Grande Cichlid, Herichthys cyanoguttatus, is a member of the Cichlid and Tilapia or Cichlidae Family, that is also known as the Texas Cichlid and in Mexico as mojarra del Norte. Globally, there are nine species in the genus Herichthys, and all nine are found in the freshwater systems of Mexico. They are the only native Cichlid in the United States.

The Rio Grande Cichlid has a “bluegill” body profile and has a light olive to dark brown background dorsally and are covered with cream and turquoise spots affording a speckled look. Lighter colored fish have 4 to 6 dark vertical bars on their sides. The females are less colored than the males. Breeding adults have a white head and front half of the body; the rear half of the body is black ventrally. Adult males have a nuchal hump on the forehead. Some fish have a very black throat. The juveniles are pearly gray with white spots on the body and fins and 2 black spots on the center of the body and caudal fin base. Their anal fins are long and tapering with 5 or 6 spines and 9 or 10 rays; their dorsal fin is long and tapering with 15 to 18 spines and 10 to 12 rays. They have one nostril opening on each side of the head and a broken lateral line that is doubled for a short distance on the caudal peduncle.

The Rio Grande Cichlid is a freshwater fish that is non-migratory and found in warm water environments (20oC/68oF to 33oC/90oF) that are high vegetated with some water flow over clay, mud, rocks and sand in creeks, lagoon, ponds, rivers and springs in the first 3 m (10 feet) of the water column. They can survive in water with a high level of pollution and salinity contents of up to 16 ppt but cannot survive water temperatures below 10oC (50oF). They reach a maximum length of 30 cm (11.8 inches) and 0.9 kg (2 lbs 0 oz) in weight with males being larger than females. The Rio Grande Cichlid is active diurnally as an omnivore with great variation observed in their diets of specimens in differing locales that include carnivorous (fish eggs, insects and small fishes), detritivores, or crustaceans, insects, plant material and worms. Reproduction occurs via monogamy or polygamy (either open polygamy or harem polygamy). Both parents providing parental care of their eggs, which hatch in 3 weeks, and fry, which become free swimming in 45 days. They reach sexual maturity in one year.

The Rio Grande Cichlid is found on a limited basis in the freshwater systems of Mexico having a native distribution in northeastern Mexico from the Verde River basin to the upper Rio Soto la Marina in the States of States of Coahuila, Nuevo León, Tamaulipas. They been introduced widely outside their native range.

The Rio Grande Cichlid is very similar to several Sunfishes and Tilapia but differ in that unlike tilapia and most sunfishes, which typically have 3 spines on the anal fin, Rio Grande Cichlids have 5 or 6. The pronounced “hump” found on the head of adult males is not present in Tilapia. They also have a single nostril opening on each side of the head and a broken two part lateral line not found in Sunfishes and Tilapia.

From a conservation perspective the Rio Grande Cichlid is currently considered to be of Least Concern with stable, widely distributed populations. They are considered to be a highly invasive, aggressive and highly territorial species competing for food, space, and spawning habitat where introduced. They are utilized by biologists to assess unbalanced or stressed ecosystems. They are targeted by recreational anglers and are a favorite of flyrod fishermen considered to be a good foe. In Mexico they are considered to be a viable food fish for humans. They are sold on a limited basis by the aquarium trade.