Reproductive biology of little tunny (Rafinesque, 1810) in the southwest Gulf of Mexico.

The aim of this study was to describe the reproductive dynamic of in the southwest Gulf of Mexico. The annual variation of the volume fraction occupied by gametes and tissues in gonads were related with main body indexes, such as the gonadosomatic index ( ), the hepatosomatic index ( ), and the nutrition index ( ), and compared with the sea surface temperature. A total of 951 individuals were sampled, where a sex ratio of 1:1 and a size interval strongly skewed towards organisms with a fork length ( ) of 36-40 cm were observed.

An integrative taxonomic approach reveals as the dominant species in the Veracruz Reef System (southwestern Gulf of Mexico).

The common octopus of the Veracruz Reef System (VRS, southwestern Gulf of Mexico) has historically been considered as , and yet, to date, no study including both morphological and genetic data has tested that assumption. To assess this matter, 52 octopuses were sampled in different reefs within the VRS to determine the taxonomic identity of this commercially valuable species using an integrative taxonomic approach through both morphological and genetic analyses. Morphological and genetic data confirmed that the common octopus of the VRS is not and determined that it is, in fact, the recently described .

Helminth parasites of the red snapper, Lutjanus campechanus (Perciformes: Lutjanidae) from the reef Santiaguillo, Veracruz, Mexico.

A total of 21 helminth species were recovered from 52 specimens of red snapper, Lutjanus campechanus , captured in the reef Santiaguillo, Parque Nacional Sistema Arrecifal Veracruzano, State of Veracruz, in the Southern Gulf of Mexico. These helminths included 9 trematodes (7 adults and 2 metacercariae), 4 nematodes (3 adults and 1 larva), 4 acanthocephalans (1 adult and 3 juvenile), 2 cestodes (both larvae), and 2 monogeneans. Sixteen of the 21 species are new host records; 7 are common species with a prevalence >40% and mean intensity >4.

Age-growth models for tilapia Oreochromis aureus (Perciformes, Cichlidae) of the Infiernillo reservoir, Mexico and reproductive behaviour.

In presence of a decrease in the catch from Infiernillo reservoir, Michoacán-Guerrero, Mexico, age and growth of tilapia Oreochromis aureus (Steindachner 1864) were estimated, as indispensable attributes for fishery management. Evaluations included scales and opercular bones readings and length frequency analysis. The population structure was determined too.