THE NATURAL HOST PLANTS OF ANASTREPHA (DIPTERA, TEPHRITIDAE) IN A TROPICAL RAIN-FOREST OF MEXICO

The relationships between Anastrepha species and their host plants are recorded and analyzed from a study carried out in a natural tropical community of Mexico (Estacion de Biologia Tropical Los Tuxtlas, Veracr uz). We sampled fruits of 55 plant species of the tropical rain forest and found the following associations: Tapirira mexicana Marchand was infested with A. sp. and A. obliqua (Macquart); Spondias radlkoferi J. D. Smith with A. obliqua; Tabernaemontana alba Mill. with A. cordata Aldrich; Quararibea funebris (Llave) Vischer with A. crebra Stone; Ing a sapindoides Willd. with A. distincta Greene; Brosimum alicastrum Sw. and Pseudolmedia oxyphyllaria J. D. Smith with A. bahiensis Costa Lim a; Psidium guajava L. with A. striata Schiner and A. fraterculus (Wied emann); Citrus aurantium L. and C. maxima (Burm.) Merrill with A. lude ns (Loew); Chrysophyllum mexicanum Brandegee ex Standley, Pouteria sap ota (Jacq.) H. Moore & Stearn and Pouteria sp. with A. serpentina (Wie demann). Also, we found the species A. hamata (Loew), A. leptozona Hen del and A. minuta Stone, whose hosts in the Los Tuxtlas region are sti ll unknown. We sampled infestation rates in 10 of the 13 host plants. Of the 3704 fruits examined, 23.1% were infested. We encountered 2290 larvae, of which 1600 pupated. Parasitoids or adult flies emerged from 85% of these. Infestation percentages of the different fruit species were highly variable, ranging from 1. 5% for P. oxyphyllaria to 66.7% for Pouteria sapota. The mean number of larvae per fruit usually was b etween 1.25 and 2.59, and in only the largest and heaviest fruits (suc h as C. aurantium, P. sapota and P. sp.) were there more than 9.0 larv ae present. Some fruit characteristics affecting the degree of infesta tion are discussed, and the possible existence of a diapause period in some Anastrepha species is noted.