Food quality influences ovarian development in scyphophorus acupunctatus (Coleoptera: Dryophthoridae)

Abstract

This paper describes the anatomy of the female reproductive system of the agave weevil, Scyphophorus acupunctatus Gyllenhall (Coleoptera: Dryophthoridae). This insect is considered a primary pest of agave (Agave spp.) (Asparagaceae) and tuberose (Polianthes tuberosa L.) (Asparagaceae) in Mexico. Developmental biology and ovarian maturation of laboratory-reared S. acupunctatus fed a meridic diet was compared with individuals fed tuberose bulbs. Ovarian maturation was classified according to ovariole and follicle differentiation, as well as the presence of follicular relics. This classification yielded 1 parous and 3 nulliparous stages. We found that ovarian maturation was delayed for those weevils fed the meridic diet compared with those fed tuberose bulbs. Also, the greatest number of ovarian follicles occurred in individuals fed tuberose bulbs; however, this relationship changed with the age of the insect. Proximal length and follicular area also varied according to age and type of diet. We believe that the ovarian developmental stages described here for S. acupunctatus could be a useful method to monitor parity status of field populations when assessing the effectiveness of control programs for this weevil pest.