Cysts and nauplii biometry characteristics of seven Artemia franciscana (Kellog, 1906) populations from Mexico

The goal of this study was to establish the biometric characteristics of cysts and nauplii of seven Artemia populations from Mexico, covering aspects related with the normal and decapsulated cysts diameter, chorion thickness, and nauplii instar I length. Cysts used for the experiment were collected in their natural habitat, cleaned, dried, and stored in the laboratory. One hundred measurements for each of the variables where done with an Olympus optical microscope equipped with a digital camera and an automated image analyzer program. To determine differences in the mean values of variables among populations, analysis of variance (ANOVA) was performed with post hoc Tukey pairwaise comparison tests. In hydrated cysts, Tukey's analysis showed no significant differences between the pairs: Yavaros/Cuatro Cienegas and Cuatro Cienegas/Texcoco. For the diameter of decapsulated cysts the same analysis indicated no significant differences in Yavaros/Cuatro Cienegas, Yavaros/Texcoco, and Cuatro Cienegas/Texcoco. Comparisons of naupliar lengths among Yavaros/Ohuira, Real Salinas/Cuatro Cienegas, and San Luis Potosi/Texcoco did not reveal differences. The Texcoco, San Luis Potosi, Yavaros, and Ohuira populations had smaller naupliar lengths than those of the San Francisco Bay populations. It is advisable to use these populations in larviculture and to consider their cultivation in their own habitats as possible viable projects.Original Abstract: El objetivo del presente trabajo fue establecer las caracteristicas de quistes y nauplios de siete poblaciones de Artemia de Mexico, cubriendo los aspectos relacionados con el diametro del quiste normal y descapsulado, grosor del corion y la longitud del nauplio. Los quistes empleados para el experimento fueron recolectados en su habitat natural. Se efectuaron 100 mediciones para cada una de las variables con la ayuda de un microscopio optico Olympus, equipado con una camara fotografica digital y un programa automatico analizador de imagenes. Para determinar diferencias entre poblaciones, se realizo un analisis de varianza (ANOVA). Al encontrar diferencias significativas se efectuo la comparacion de medias multiples por el metodo de Tukey. En cuanto al diametro de quistes, la tecnica de Tukey demostro que no existian diferencias significativas entre los pares: Yavaros/Cuatro Cienegas y Cuatro Cienegas/Texcoco. Para el diametro de quistes descapsulados, el mismo analisis no demostro diferencia significativa en Yavaros/Cuatro Ci