Frank, S. A. 1984. The behavior and morphology of the fig wasps Pegoscapus assuetus and P. jimenezi: Descriptions and suggested behavioral characters for phylogenetic studies. Psyche 91:289-308.

Figs (Ficus spp., Moraceae) and their pollinator wasps (Agaonidae) are the most intricately coevolved of the plant-insect mutualisms. The necessity of the tiny wasps for good fruit set in cultivated figs [Ficus carica (L.)] was recognized over two thousand years ago by Aristotle and his pupil Theophrastus, and the details of pollination in this species were understood by the early part of this century (Condit 1947). It was only fifteen years ago, however, that the tremendous diversity in pollination mechanisms among the approximately 900 species of figs began to be appreciated (Ramirez 1969; Galil and Eisikowitch 1969; Chopra and Kaur 1969). It is generally accepted that each fig species is pollinated by a unique species of fig wasp (Ramirez 1970a; Wiebes 1979). There is much variability in fig inflorescence morphology, which is associated (by host specificity) with variability in fig wasp morphology (Ramirez 1974) and behavior (Galil and Meiri 1981). Although general trends in the mechanism of pollination across subtaxa of Ficus and Agaonidae can be inferred from fig inflorescence and fig wasp morphology (Ramirez. 1974), the actual details of both pollen collecting and pollination by the wasps have only been studied in a few species. Among the monoecious figs, Galil and Snitzer-Pasternak (1970) studied the pollination of Ficus religiosa (L.) by the fig wasp Blastophaga quadraticeps (Mayr); Galil and Eisikowitch (1969, 1974) studied F. sycomorus (L.) and its pollinator Ceratosolen arabicus (Mayr); Joseph and Abdurahiman (1981) described pollination of F. racemosa (L.) by C. fusciceps (Mayr); and Galil et al. (1973) observed the pollination of F. costaricana [(Liebman) Miquel] and F. hemsleyana (Standley) by B. estherae (Grandi) and B. tonduzi (Grandi), respectively. Among the dioecious figs, Galil (1973) reported on pollination of F.fistulosa (Reinw. ex Bl.) by C. hewitti (Waterston); Galil and Neeman (1977) described the details of pollen transfer and pollination in the edible fig F. carica (L.) by B. psenses (L.); and Okamota and Tashiro (1981) characterized a remarkable mechanism of pollen transport and pollination in F. erecta (Thunberg) by B. nipponica (Grandi).

The general features of the pollination cycle of monoecious figs have been described by Galil and co-workers (see above), and reviewed by Janzen (1979) and Wiebes (1979). In this paper I present a detailed description of the pollination cycles of Ficus aurea (Nuttall) and F. citrifolia (P. Miller), which are pollinated by the fig wasps Pegoscapus jimenezi (Grandi) and P. assuetus (Grandi), respectively (see Wiebes 1983 for taxonomic discussion of these fig wasp species). The two fig species are closely related members of the monoecious section Urostigma. New information presented in this paper includes detailed scanning electron micrographs of the morphology associated with pollination by Pegoscapus jimenezi, and detailed descriptions of the behavior during entry into the fig inflorescence, during pollination, and during pollen collecting by P. jimenezi and P. assuetus in Florida. These behaviors are very similar to those described by Galil et al. (1973) in Costa Rica for the fig wasps Blastophaga (=Pegoscapus) estherae and B. tonduzi. which pollinate Ficus costaricana and F. hemsleyana, respectively. However, clear differences in behavior exist between the fig wasps discussed in this paper and the descriptions of the two Costa Rican species. The usefulness of these behavioral characters for the study of fig wasp phylogeny will be explored in the discussion.


Download reprint