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   Figs:     Part 1       Part 2       Cystoliths       Pollinators 1        Pollinators 2        Pollinators 3        Pollinators 4  
Fig Pollinators At Palomar College 4
© W.P. Armstrong Updated 4 July 2025

Special thanks to Dr. Jean-Yves Rasplus of Paris University Orsay, Research Director at French National Institute for Agriculture, Food, & Environment (INRAE), and coauthor of Figweb (figweb.org). He is an international authority on taxonomy of figs and their symbiotic wasps, and has published hundreds of peer-reviewed articles on the subject. In fact, he identified and verified many of the names on this page. I have referred to his personal communication (4 July 2025) several times on this page.

     1. Ficus rubiginosa         2. F. macrophylla         3. F. microcarpa  

Note: Pollinator fig wasps on this page (Pleistodontes and Eupristina) belong to the family Agaonidae and nonpollinators belong to family Epichrysomallidae. Both families are members of the enormous superfamily Chalcidoidea with over 22,000 described species. There are estimates of up to 500,000 species of chalcidoid wasps.

1. Fig Wasps in Syconia of Ficus rubiginosa in Arboretum

According to Rasplus (4 July 2025), the above image is undoubtedly Ficus rubiginosa. "There are several "forms" of rubiginosa across Australia that have been lumped into the nominal species. The one shown--with thick leaves and orange pubescence on the underside--is typically found along the coast in sandy, warm areas. Whether these forms deserve taxonomic distinction is a question that would require a thorough genetic study."

Syconia on Ficus rubiginosa variant near Moreton Bay Fig (F. macrophyllla) in Palomar College Arboretum contain 3 genera of fig wasps: Pleistodontes, Sycoscapter, & Herodotia. "Host-sharing" is when 2 or more pollinator species share a single host fig species. "Pollinator-sharing" is when 2 or more host fig species share a single pollinator wasp species. Only Pleistodontes imperialis in the above image is a pollinator. At least 5 fig species on the Palomar College campus & the San Diego Zoo share this wasp species.

Nonpollinators in family Epichrysomallidae from fig syconia in above image.
(Pleistodontes species on this page are fig pollinators in family Agaonidae.)

#1. According to Rasplus (4 July 2025): This is "very likely" male Herodotia subatriventris Girault, 1923; and #2. female Herodotia subatriventris (In the family Epichrysomallidae).

Syconia of fig identified by Rasplus as variant of Ficus rubiginosa.

Epichrysomallidae: Male Herodotia subatriventris Girault, 1923. According to Rasplus (4 July 2025), the Sycoscapter is a new species associated with Ficus rubiginosa. There are still many undescribed species linked to Australian Malvanthera. Although it is listed here as cf. ("compare with"), a precise specific epithet is probably premature at this time.

Male wasp tentatively identified as cf. Sycoscapter australis.

Apparently, when male wasps compete for females within the syconium they engage in violent, often fatal fights. Their wicked mandibles suggest they are adapted for more than chewing holes in syconium wall to release winged females like in other fig wasp species. Fatal fights are rare in the majority of animal species but are a common component of mate competition between wingless males of some species of fig-associated wasps. In fact, one study investigated fatal fighting in the nonpollinating wasp Sycoscapter australis, and about 25% of males sustained fatal injuries during the mate competition period.

2. Fig Wasps in Syconia of Ficus macrophylla in Arboretum

Massive trunk and surface roots of a Moreton Bay fig (Ficus macrophylla) in the Palomar College Arboretum. In its native Australia it is a strangler fig.

Mature wasp-bearing syconia on Moreton Bay fig (Ficus macrophylla) in Palomar
College Arboretum. Syconia contained pollinator wasp Pleistodontes froggatti.

Pleistodontes froggatti from Moreton Bay fig and the smaller P. imperialis from nearby rustyleaf fig, both in the Palomar College Arboretum. I have only observed P. froggatti in Moreton Bay fig (F. macrophylla); however, P. imperialis exhibits pollinator sharing and occurs in 5 observed Ficus species, including F. rubiginosa, F. pleurocarpa, F. obliqua, F. vasta, and F. watkinsiana. The latter species was observed at San Diego Zoo.

There are some noteworthy differences between these 2 species of Pleistodontes, including shape of head, length of scape (basal segment of antennae), & toothed, mandibular appendage below head.

A difference between Pleistodontes froggatti & P. imperialis males is the color of their heads.

3. Fig Wasps in Syconia of Ficus microcarpa at Palomar College

According to Rasplus (4 July 2025), Eupristina verticillata is the name commonly used for the invasive pollinator that has spread across nearly all tropical regions along with its host fig, Ficus microcarpa. "However, this identification is actually incorrect, though the name has yet to be revised. There are at least 14 distinct species of Eupristina associated with F. microcarpa across its range, and the one we have here in the state remains undescribed. That said, you can still refer to it as E. verticillata for now."

Pollinator sharing has been reported for the Indian laurel fig Ficus microcarpa; however, I have only observed the primary symbiotic wasp Eupristina verticillata at Palomar College. Syconia in June 2025 had relatively few wasps, but were loaded with seed-bearing drupelets (see above image). Birds apparently feed on the abundant reddish syconia of this invasive fig and disperse the viable seeds throughout the campus.

Seedling Indian laurel fig Ficus microcarpa on steps
of Multidisciplinary Building (MD) at Palomar College.