[Feeding habits of sphoeroides testudineus (Perciformes: Tetraodontidae) in the lagoon system of Ria Lagartos, Yucatán, Mexico].

Sphoeroides testudineus is a dominant species in the coastal systems of Yucatán. Because of its wide distribution, occurrence and abundance performs an important functional role in coastal ecosystems. We assessed the trophic preferences and trophic-level variation in space and time for this species in Ria Lagartos lagoon, an hyperhaline ecosystem located Northwest of Yucatan Peninsula.

Day and night trophic variations of dominant fish species in a lagoon influenced by freshwater seeps.

The aim of this study was to determine the trophic structure and nycthemeral variations in the diet of dominant fish species (Ariopsis felis, Bairdiella chrysoura, Micropogonias undulatus, Eucinostomus gula, Eucinostomus argenteus, Lagodon rhomboides and Sphoeroides testudineus) in Celestun Lagoon, a biosphere reserve located in the southern Gulf of Mexico, and influenced by freshwater seeps. A total of 1473 stomachs were analysed and nine trophic groups were recorded. Bray-Curtis analyses with analyses of similarity (ANOSIM) statistical tests were used to determine two groups of feeding guilds: zoobenthivores and omnivores, with significant differences between time and habitat.

[Feeding changes for three Sphoeroides species (Tetraodontiformes: Tetraodontidae) after Isidore hurricane impact in Carbonera Inlet, Southeastern Gulf of Mexico].

The coexistence of ecologically similar species may occur because of resources distribution, such as prey and habitat type and segregation time, that minimizes the interspecific competition. The changes brought about by Hurricane Isidore in the distribution of food resources by three coexisting fish species of the family Tetraodontidae (Sphoeroides nephelus, S. spengleri and S testudineus), were analyzed at the Carbonera Inlet.

[Ichthyofauna of karstic wetlands under anthropic impact: the "petenes" of Campeche, Mexico].

"Petenes" are small springs and associated streams that drain into wetlands near the coast in karstic areas. We studied composition, distribution, and abundance of the ichthyofauna in Los Petenes region (northwest Campeche). Two petenes displaying different degrees and types of anthropic impact were selected, Hampolol and El Remate.

Spatial and temporal characterization of fish assemblages in a tropical coastal system influenced by freshwater inputs: northwestern Yucatan Peninsula.

Coastal lagoons are important systems for freshwater, estuarine and marine organisms; they are considered important zones of reproduction, nursery and feeding for many fish species. The present study investigates the fish assemblages of the natural reserve of Dzilam and their relationship with the hydrologic variables. A total of 6 474 individuals (81 species) were collected, contributing with more than 50% considering the Importance Value Index (IVI), Sphoeroides testudineus, Fundulus persimilis, Anchoa mitchilli, Eucinostomus gula, Eucinostomus argenteus and Mugil trichodon.