Postembryonic development ad population parameters of Alpaida veniliae (Keyserling, 1895) (Araneae, Araneidae), in laboratory.

BENAMU, M., SANCHEZ, N. & A. GONZALEZ.

JOURNAL OF NATURAL HISTORY

TAYLOR & FRANCIS LTD

Año: 2011 vol. 45 p. 1607 - 1617

0022-2933

Abstract. We studied postembryonic development from hatching to adult stage and determined life history traits and population parameters of Alpaida veniliae. It is one of the most abundant species of the orb weaving guild of the spider community of soybean crops in Buenos Aires province, Argentina. The first three instars occurred inside the egg sac, and nymph IV (spiderlings) started the dispersion from it.  Alpaida veniliae female achieved greater adult size and larger adult longevity than the male. Mean fecundity, mean number of egg sacs per female, mean number of eggs per egg sac, as well as the net reproductive rate, the intrinsic rate of increase (r),  the generation time (T), and the reproductive values (Vx) of three cohorts, were determined under laboratory conditions, indicating a relatively high capacity for growth. Their biological and ecological attributes indicate the importance of conservation this predator as a natural enemy of soybean crop pests.