All of the seven most species-rich plant families also included the greatest number of plant species with galls: Fabaceae (29), Melastomataceae (23), Rubiaceae (23), Araceae (21), Moraceae (17), Piperaceae (16), and Asteraceae (16) (Table 2).
With respect to the gall-inducers the vast majority of the galls were induced by Cecidomyiidae (Diptera), while the second most common category was "gall-inducer uncertain".
Inquilines coexist with the gall inducer when they both feed on the same tissue; e.g., the hymenopteran inquiline Periclistus pirata Osten Sacken (Hymenoptera: Cynipidae) on stem galls of Diplolepis nodulosa Beutenmuller (Hymenoptera: Cynipidae) (Brooks & Shorthouse 1997).
The primary characteristic that differentiates inquilinism from the other guilds is their stimulation of the host plant to produce new tissue in galls (Brooks & Shorthouse 1997).
The galls were collected at the Reitor Edgard Santos campus of the Universidade Federal do Oeste da Bahia (UFOB) in a dry forest area of the Brazilian Savannah (Cerrado) (11[degrees]37' and 12[degrees]25'S and 44[degrees]34' and 46[degrees]23'W) located in the municipality of Barreiras, Bahia State, Brazil.
In the laboratory, a portion of the galls was dissected under a stereo microscope to identify the gall inducers.
Analysis of Withered Galls. After the end of ACGW emergence in our study sites, withered galls still present on the chestnut trees were collected to assess the natural mortality of both the ACGW and its parasitoids.