Slender Mojarra, Eucinostomus jonesii

Slender Mojarra, Eucinostomus jonesii. Fish caught from coastal waters off Punta Nizuc, Cancun, Quintana Roo, July 2015. Length: 10 cm (3.9 inches). Catch, photograph and identification courtesy of Marc Eberlein, Grand Rapids, Michigan.

Slender Mojarra, Eucinostomus jonesii. Fish caught from coastal waters off Belize, July 2015. Length: 12 cm (4.7 inches). Catch, photograph, and identification courtesy of Josh Leisen (joshadventures.com), Gaylord, Michigan.

Slender Mojarra, Eucinostomus jonesii. Fish caught from coastal waters off of Caye Ambergris, Belize, June 2013. Length: 13 cm (5.1 inches). Catch, photograph and identification courtesy of Eli (obsessiveangling.wordpress.com).

Slender Mojarra, Eucinostomus jonesii. Fish caught from coastal waters off Sugarloaf Key, Florida, August 2014. Length: 14 cm (5.5 inches). Catch and photograph courtesy of Dean Kimberly, Atlanta, Georgia.

Slender Mojarra, Eucinostomus jonesii. Fish caught off the Grand Mayan Pier, Cancun, Quintana Roo, February 2019. Length: 18 cm (7.1 inches). Catch, photograph and identification courtesy of George Brinkman, Guelph, Ontario, Canada.

Slender Mojarra, Eucinostomus jonesii. Fish caught off beach in Ft. Lauderdale, Florida, April 2019. Length: 18 cm (7.1 inches). Catch, photograph and identification courtesy of Luke Ovgard, Klamath Falls, Oregon.

The Slender Mojarra, Eucinostomus jonesii, is a member of the Mojarra or Gerreidae Family, and is known in Mexico as mojarra flaca. Globally, there are eleven species in the genus Eucinostomus and all eleven are found in Mexican waters, seven in the Atlantic and four in the Pacific Ocean.

The Slender Mojarra has an elongated oval body that has a depth that is 30% to 32% of standard length. They have silvery bodies with no other distinguishing marks. Their head has a pointed snout and a highly protrusible mouth. In fish longer than 5 cm (2 in), the anal fin has 3 spines; their caudal fin is deeply forked, and, their dorsal fin has 9 spines and 10 rays. They have 7 or 8 gill rakers on the lower arch. Their body is covered with small scales.

The Slender Mojarra is a schooling species that reside in coastal areas and are found in sandy areas, within reefs, and on occasion in deeper waters at depths up to 45 m (148 feet). They reach a maximum of 20.0 cm (7.9 inches) in length. They are benthic feeders consuming bivalves, invertebrates, and polychaete worms. The Slender Mojarra is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Slender Mojarra is a resident of all Mexican waters of the Atlantic Ocean including the Gulf of Mexico and the Caribbean.

The Slender Mojarra is most likely confused with the Mottled Mojarra, Eucinostomus lefroyi (mottled coloration with 6 wavy lateral lines connected by 8 lateral dots).

From a conservation perspective the Slender Mojarra is currently considered to be of Least Concern with stable, widely distributed populations. They are small in stature and of limited interest to most, however, they are utilized as a live bait by recreational fishermen on occasion.

NOTE.  There are eighteen members of the Mojarra or Gerreidae Family currently Included in this website, ten are from Mexican waters of the Pacific and eight from the Atlantic. They are all very similar in appearance and difficult to identify.  As an aide to this challenge I have assembled a Mojarra Body Depth Chart that presents these seventeen mojarras from thin bodied to deep bodied which is useful in identification work. In addition, I have also assembled a Mojarra Maximum Length Chart which I have also helpful in the identification work for these eighteen mojarras. Both charts can be found at the end of the Mojarra Family Page.