File: <agaonid.htm> [For educational purposes only] Glossary <Principal Natural Enemy Groups > <Citations> <Home>

HYMENOPTERA, Agaonidae (Chalcidoidea) -- <Images> & <Juveniles>

Agaonidae -- There are two species of fig wasps, Blastophaga psenes (L.) and Secundeisenia mexicana (Ashmead), in North America, with B. psenes having been introduced to allow for the production of some commercial figs.

The Smyrna fig, which is grown in California, produces fruits only when it is pollinated with pollen from the wild fig, or caprifig, the pollination being accomplished by fig wasps. These develop in a gall in flowers of the caprifig. The blind and flightless males emerge first and may copulate with females inside the galls. The female, on emerging from the gall, collects pollen from male flowers of the Capri fig and stores it in special baskets or corbiculae. The female pollinates figs of both types (Smyrna fig and Capri fig), but oviposits successfully only in the shorter flowers of the Capri fig. Fig growers usually aid in the process of Smyrna fig pollination by placing in the fig trees branches of the wild fig.

The Agaonidae pollinate figs or are otherwise associated with figs, a coevolutional relationship that has been developing for at least 80 million years. The family as presently defined is polyphyletic, including several unrelated lineages whose similarities are based upon their shared association with figs; efforts are underway to resolve the matter, and remove a number of constituent groups to other families, particularly the Pteromalidae and Torymidae. Thus, the number of genera in the family is in flux. Probably only the Agaoninae should be regarded as belonging to the Agaonidae, whilst the Sycoecinae, Otitesellinae and Sycoryctinae should be included in the Pteromalidae. Placement of the Sycophaginae and Epichrysomallinae remains uncertain.

Among the Agaonidae, the female is a normal insect, while the males are mostly wingless. The males' only tasks are to mate with the females while still within the fig syconium and to chew a hole for the females to escape from the fig interior. This is the reverse of Strepsiptera and the bagworm, where the male is a normal insect and the female never leaves the host.

Most fig inflorescences contain three kinds of flowers: male, short female, and long female. Female fig wasps can reach the ovaries of short female flowers with their ovipositors, but not long female flowers. Thus the short flowers grow wasps, whereas the long flowers become seeds. In figs of this sort, the crunchy bits in the fruit contain both seeds and wasps. However, there are several commercial and ornamental varieties of fig that are self-fertile and do not require pollination; these varieties are not visited by fig wasps.

Pollinating fig wasps (Agaoninae) are specific to specific figs. The common fig Ficus carica is pollinated by Blastophaga psenes.

References: Please refer to <biology.ref.htm> [Additional references may be found at: MELVYL Library]

Boucek, Z. 1988. Australasian Chalcidoidea, a biosystematic revision of genera of fourteen families, with a reclassification of species. CAB Internatl., Wallingford, UK. 832 p.

Grandi, G. 1920. Studio morfologico e biologico della Blastophaga psenes (L.). Boll. Lab. Zool. Gen. Agr. Portici 14: 62-203.

Grandi, G. 1961. The hymenopterous insects of the superfamily Chalcidoidea developing within the receptacles of figs. Their life history, symbioses and morphological adaptations. Boll. 1st. Ent. Univ. Bologna 26: 1-13.

Grandi, G. 1963. Catalogo ragionato degli Agaonidi del mondo descritti fino a oggi (6a edizione). Boll. 1st Ent. Univ. Bologna 26: 319-73.

Hill, D. S. 1967. Fig-wasps (Chalcidoidea) of Hong Kong. 1. Agaonidae. Zool. Verh. 89: 1-55.

Nikol'skaya, M. N. 1978/1987. Family Agaonidae (Agaonids). In: G. S. Medvedev (ed.) 1987, Keys to the Insects of the European Part of the USSR. Vol. 3 Hymenoptera, Pt. 2. Akad. Nauk., Zool. Inst., Leningrad, SSSR. (trans. fr. Russian, Amerind. Publ. Co., Pvt. Ltd., New Delhi). 1341 p.

Prinsloo, G. L. 1980. An illustrated guide to the families of African Chalcidoidea (Insecta: Hymenoptera). Rep. So. Africa, Dept. Agr. & Fisheries Sci. Bull. 395. 66 p.

Wiebes, J. T. 1966. Provisional host catalogue of fig wasps (Hymenoptera, Chalcidoidea). Zool. Verh. 83: 1-44.

Wiebes, J. T. 1974. Nigeriella, a new genus of a West African fig wasp allied to Elisabethiella Grandi (Hymenoptera, Chalcidoidea, Agaonidae). Zool. Meded. 46: 29-42.