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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.
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