|Crop Knowledge Master|
Bephratelloides cubensis (Ashmead)
|Annona Seed Wasp|
Ronald F.L. Mau, Extension Entomologist
Jayma L. Martin Kessing, Educational Specialist
Department of Entomology
This pest attacks fruit belonging to the Annona genus. Fruits include atemoya, cherimoya, custard-apple, ilama, soursop and sugar-apple.
First reported in Cuba, this insect occurs in Central and South America, Florida, Hawaii, Mexico and the West Indies. Its host, Annona spp., is native to Africa, however the annona seed wasp has not been reported there. It was reported on Oahu in 1986 and on the Big Island in 1989.
Two kinds of injury occur due to this pest: 1) consumption of the seed by the developing larvae and 2) tunneling through the fruit by adults. The latter is the main source of economic damage.
Early stages of infestation are not readily detectable. Emergence holes in the surface of the fruit are the first sign of infestation. Principal injury is attributed to the tunnel (1/8 inch in diameter) formed by the adult when it emerges from the fruit. Only one adult exit tunnel is formed per infested seed. In green fruit, a hardened callus forms around the edge of the tunnel that remains open and becomes a permanent injury. In ripe or ripening fruit, decay starts in the emergence tunnels and sometimes spreads throughout the fruit. In heavy infestations the fruit surface is dotted with many emergence holes.
Life cycle duration of the annona seed wasp ranges from 66 to 87 days. In Florida, there are probably 4 generations per year (Pena, et. al., 1984). Although sexual reproduction occurs in this species, populations are usually comprised of females producing females through non-sexual reproduction.
Eggs are oviposited within developing seeds when fruits are 1-1/2 to 2 inches in diameter. They are ovoid with a short filament at one end and a long filament that extends out of the oviposition puncture at the other end. While many eggs are laid within a single seed, only one mature larva develops. Incubation lasts 12 to 14 days.
Larvae are translucent white to cream in color, legless, C-shaped, distinctly segmented, swollen at the center and gradually tapered to points at the ends. They are fully grown (about 3/8 inch) in 42 to 55 days.
The naked pupae are protected by the seed coat and develop into adults in 14 to 21 days.
The red eyed adults are small (1/3 inch long), varying in color from reddish brown to light brown with a dusty blotch on each wing. The shiny abdomen is longer than the head and thorax combined. The base of the abdomen in compressed in a hump-like fashion gradually tapering into a upwards curve at the tip where white hairs are present. The female's ovipositor at the tip of the abdomen is as long as her body.
After the adults emerge from the seed casing they require several days to chew tunnels to the surface of the fruit. Females begin ovipositing within a day after emerging from the fruit, and they live for up to 11 days.
Adults are diurnal, being most active in mid- to late afternoon.
Field sanitation is of utmost importance. Infested fruit serve as a source of wasps for reinfestation and must be removed from the orchard. If this is done, it is likely that there will be reduced infestations during the next fruiting season.
An alternate means of obtaining uninfested fruit is by bagging individual fruits when they are 1- 1/2 to 2 inches in diameter.
Ashmead, W. H. 1894. Bephrata cubensis sp. n. Trans. Am. Ent. Soc. 21: 321-322.
Dozier, H. L. 1932. Two Important West Indian Seed-Infesting Chalcid Wasps. Puerto Rico Dept. Agric. Jour. 16: 109-112.
Grisell, E. E. and M. E. Schauff. 1990. A synopsis of the Seed-Feeding Genus Bephratelloides (Chalcidoidea: Eurytomidae). Proc. Entomol. Soc. Wash. 92(2): 177-187.
Heu, R. 1988. Bephratelloides (Bephrata) cubensis in Minutes, Notes and Exhibitions., February. Proc. Hawaiian Entomol. Soc. 28:4.
Krombein, K. V., P. D. Hurd, D. R. Smith, B. D. Burks. 1979. Catalog of Hymenoptera in America North of Mexico. Volume 1: Symphyta and Apocrita (Parasitica). Smithsonian Institute Press, Washington DC. 1198 pages.
Martonell, L. F. 1945. Forest Insects of Puerto Rico. Puerto Rico Univ. J. Agric. 29: 557.
Pena J. E., H. Glenn and R. M. Baranowski. 1984. Important Insect Pests of Annona spp. in Florida. Proc. Fla. State Hort. Soc. 97: 337-340.
Wolcott, G. N. Insects Attacking Fruits, Fruit Borer. pp. 521-522. In Economic Entomology of West Indies. 688 pages.