Juvenile development, ecdysteroids and hemolymph level of metabolites in the spider Brachypelma albopilosum (Theraphosidae).

In the present work, juvenile development and physiological state of mygalomorph Brachypelma albopilosum were investigated by means of individual rearing under controlled conditions. Males required 4–5 years for development from first juvenile instar to adulthood, passing through 8 to 12 juvenile molts. Females developed to adults in 5–6 years with a variable juvenile molt number from 9 to 13. The development and growth of males and females took place in a similar way until the last juvenile molt leading to subadults. Ecdysteroids, total lipid, cholesterol, and protein concentrations increased along with the different development instars in both males and females. After the last juvenile molt, spiders presented morphological and biochemical sex differences. Subadult and adulthood males were smaller in size and weight than females; hemolymph levels of ecdysteroids, total lipids, cholesterol, and glucose were higher in males. These physiological and biochemical differences can be correlated to the different sexual development between males and females. J. Exp. Zool. 317:236–247, 2012. © 2012 Wiley Periodicals, Inc.