Development, survival and description of the life stages of Zatrephina lineata (Coleoptera: Chrysomelidae) fed on Ipomoea pes-caprae leaves.

ABSTRACT

Zatrephina lineata (Coleoptera Chrysomelidae) is a phytophagous insect, mainly of plants of the genera Ipomoea and Mikania. The objective was to study the development, survival and to describe the life stages of Z. lineata fed on leaves of Ipomoea pes-caprae. Biological observations were made daily with the aid of a stereoscopic microscope and the instars of this insect identified by the exuvia left between one moulting and the next. The duration of development and survival of the egg, larva and pupa stages and the first, second, third, fourth and fifth instars and of the nymph stage of Z. lineata differed, but not between sexes of this insect. The duration of development of Z. lineata was longer in the larval stage and in the fifth instar, and its survival greater in the egg and pupa stages and in the first and fifth instars. Zatrephina lineata eggs, cream-colored, are ellipsoid and deposited in groups on the adaxial surface of older I. pes-caprae leaves. The larvae of this insect go through five instars, with the first three being gregarious with chemo-behavioral defenses. The exarated pupae of Z. lineata, light yellow in color and with an oval shape flattened dorsoventrally, attach to the abaxial surface of the I. pes-caprae leaves. The shape of adults of this insect is oval, straw yellow in color with lighter longitudinal stripes and females are slightly larger than males.