Jack Dempsey, scientifically known as Rocio octofasciata, is a type of cichlid fish that lives in freshwater areas from southern Mexico to Honduras. It also exists in other places where it was introduced.
The name “Jack Dempsey” comes from a famous 1920s boxer because this fish is aggressive and has strong facial features like him.
Jack Dempsey likes to live in warm, swampy waters that are not very clear. It’s found in places with lots of plants, muddy bottoms, or sandy bottoms like canals and drainage ditches.
The Jack Dempsey cichlid usually stays near the coast and enjoys slow-moving rivers.
Jack Dempsey eats worms, crustaceans, insects, and other fish in their natural environment. Here’s the complete guide on taking care of Jack Dempsey cichlids.
Jack Dempsey Interesting Facts
- Named after a 1920s boxer, the aggressive Jack Dempsey cichlid thrives in warm, swampy waters with lots of plants and muddy or sandy bottoms.
- Found from southern Mexico to Honduras, they eat worms, crustaceans, insects, and other fish.
- This fish can grow up to a maximum length of 9.8 inches (25.0 centimeters) long and have distinct features like 17 to 19 dorsal spines and an acute ventral angle of articular.
- As caring parents, both mother and father protect their eggs on surfaces like rocks or sand and watch over their babies after hatching.
Jack Dempsey Habitat
Jack Dempsey originates from North and Central America. It’s found in the Atlantic slope region, ranging from southern Mexico’s Papaloapán River to Honduras’ Ulua River.
This freshwater fish lives near the bottom of the water (benthopelagic) and prefers a pH range of 7.0 to 8.0 with a dH range of 9 to 20. The ideal temperature is between 72°F to 86°F (22°C to 30°C).
Jack Dempsey thrives in tropical environments located at latitudes between 21°N to 14°N.
| Water Temperature: | 72°F to 86°F (22°C to 30°C) |
| Water pH: | 7.0 to 8.0 pH |
| Water Hardness: | 9 to 20 dH |
Jack Dempsey Physical Characteristics
Size: 2.9 inches (7.5 centimeters)
Jack Dempsey can grow up to a maximum length of 9.8 inches (25.0 centimeters) but usually reaches around 2.9 inches (7.5 centimeters) long.
This fish has 17 to 19 dorsal spines, 8 to 10 dorsal soft rays, 8 to 9 anal spines, and 7 to 9 anal soft rays.
Jack Dempsey’s sides have small spots that form about 15 regular lines. Its belly is mostly white or gray in color.
Unlike the similar Rocio gemmata and Rocio ocotal species, Jack Dempsey has some distinct characteristics like an acute ventral angle of articular, a forward-facing first neural spine, as few as 17 circumpeduncular scales (instead of more than 19), and a distance between the caudal esophageal loop in the gut and esophagus that is always over 24% of the gut length (instead of less than16%).
However, there are no unique features that set this species apart completely from others.
Jack Dempsey Reproduction
Jack Dempseys lay their eggs on surfaces like rocks or sand.
Both parents protect the eggs and watch over their babies after they hatch.
Jack Dempsey Scientific Classification
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Cichliformes |
| Family: | Cichlidae |
| Genus: | Rocio |
| Scientific Name: | Rocio octofasciata |
| Also Known As: | Jack Dempsey |
| Conservation Status: | Least Concern |
great info. I think I must have two males because they are about 6 years old and quite large with the larger one recently attacking the face of the other, however that has stopped and it appears to be healed up. Also, I have a 55 Gal.