Biological characteristics of <i>Moolgarda cunnesius</i> (Valenciennes, 1836) in Thua Thien Hue, Vietnam

Moolgarda cunnesius (Valenciennes, 1836) is a species of the Mugilidae family, commonly known as a delicious fish with high nutritional and economic value, making it very promising. Zoological research methods and DNA barcoding are used to study this fish. Morphological Characteristics: The Leaf mullet has 62 to 75 gill rakers on the lower limb of the first gill arch. The upper jaw is slightly curved downward, and the anterior margin of the anterior alveolar is slightly concave. The body has 37 to 43 scales. The first dorsal fin has 4 spines, while the second dorsal fin is smaller and starts behind the anal fin. Pectoral Fins: These fins are 2/3 of the head length. Anal and Pelvic Fins: These fins are small. The second dorsal and anal fins have few scales, with scales only on the anterior and basal parts. The dorsal surface is green, the flanks and abdomen are iridescent silver, and the fins are slightly dull. There is a difference in the measurement criteria between the study areas, but there is no difference between male and female groups. Mahalanobis distance analysis showed no conformational difference between male and female groups of M. cunnesius and no similarity between sexes. Nutritional biological characteristics: The food composition includes a variety of zooplankton phytoplankton benthic animals, and organic detritus. Organic humus has the highest occurrence, followed by dinoflagellates, blue-green algae, diatoms, and the lowest is arthropods. This diverse food composition illustrates that M. cunnesius is an omnivorous species. Genetic Characteristics: COI gene DNA barcoding was used to study the genetic diversity of M. cunnesius in two regions of the North and the South of Tam Giang lagoon. Amplified and sequenced 10 samples of the COI gene of M. cunnesius in Tam Giang lagoon recorded a size of 650 bp. The rate of difference in COI sequences of the 2 samples is low compared to previous studies. The similarity coefficient of M. cunnesius in the two areas of Tam Giang lagoon is very high (0.9953).