Medusozoans of Tuxpan, Veracruz, Gulf of Mexico

Abstract

Except for true jellyfish (Scyphozoa), other medusozoans are poorly known in the northern region of Veracruz, Mexico. The present study provides an updated list of the medusozoans, their taxonomical descriptions, species richness, and community structure seasonal variations in the Tampamachcoco lagoon and the neritic zone off the Tuxpan coast, Veracruz, Mexico. Plankton collections were carried out in coastal ecosystems during the Nortes (cold front; October 2018) and dry (June 2019) periods using a conical net with a 70 cm diameter and 250μm mesh size. Nineteen species, 12 families, six orders, and two classes (Scyphozoa and Hydrozoa) were identified. Geographic distribution of the siphonophore Chelophyes contorta for the Gulf of Mexico expanded from the Caribbean Sea to the Gulf of Mexico. The highest medusozoan richness was recorded in the neritic zone, with 13 species, of which nine species belonged to Siphonophora. In contrast, only two scyphozoans and five hydrozoans were recorded in the Tampamachoco lagoon. In the neritic zone, changes were found in the composition and density of medusozoans between the Nortes and dry periods. This could be related to the cold and warm waters in these climatic periods that affect the medusozoan’s community structure. We recommend conducting detailed studies on the effects of environmental variables on the richness and community structure of medusozoans in the region.