S. Mahunka szerk.: Folia Entomologica Hungarica 64. (Budapest, 2003)

pilulae (Diptera: Cecidomyiidae) (Walsh 1864). The communities associated with aylacine galls (Cynipidae: Aylacini) are almost free of cynipid inquilines (Askew 1984, Jones 1983). Known exceptions are species in the genus Synophromorpha Ashmead, 1903, which are developing within galls, induced by Diastrophus species on bramble, Rubus (Burks 1979, Ritchie & Shorthouse 1987). Inquiline cynipids have lost the ability to induce their own galls, nevertheless they are able to induce the development of larval chambers lined with nutritive tissue inside the galls induced by other cynipids (Ronquist 1994, Shorthouse 1973, 1980). Some inquiline cynipids are also able to modify the size and/or shape of the host gall substantially, both in oak galls (e.g. Synergus clandestinus Eady, 1952 in the galls of Andricus legitimus Wiebes-Rijks, 1980 (Wiebes-Rijks 1980), and Ceroptres clavicornis Hartig, 1840 in galls of Andricus hispanicus (Hartig, 1856) and A. kollari (Hartig, 1943) (Pujade-Villar 1991)) and rose galls (Brooks & Shorthouse 1997, Shorthouse 1980). Thus, the cynipid inquilines are also phytophagous insects, like the gall wasps. However, inquiline larvae can develop inside the gall-inducer'

s chamber and then usually cause the death of the gall-inducer cynipid larvae, or locate and feed in the peripherical tissue of the gall and also can provoke or not the death of the gall inducer larvae, especially when the number of inquilines is high. Thus, they can affect the gall inducer negatively (Wiebes-Rijks & Shorthouse 1992) or do little harm to the gall-inducer (Mayr 1872). Despite of it, inquiline larvae do not behave like parasitoids (Evans 1965, Shorthouse 1973, 1980, Wiebes-Rijks 1980) but compete for the food source and/or space. For this reason, Ronquist (1994) defines this unilateral relationship as "agastoparasitism" instead of inquilinism. The relationships between inquilines and their host gall wasps were divided by Duftet (1968) into three models: 1) lethal inquilines if they always cause the death of the gall inducer; 2) non-lethal inquilines that never cause the death of the host cynipid; and 3) facultative inquilines, when the impact on host larva depends on the localization of the inquiline larvae in the gall. For example, Synergus nervosus Hartig, 1840 attacks galls of the asexual generation of Cynips quercusfolii Linnaeus, 1758 early in their development, causing the death of the gall-inducer. Several eggs are laid, and the resulting larvae compete amongst themselves until only one remains (Wiebes-Rijks 1982). Though this group of lethal inquilines does not directly kill or feed on the gall-inducer, they may impose substantial mortality on it (Schönrogge etal. 1994a, b, 1996a, b, Washburn & Cornell 1981). In the asexual generation galls of the oak gall wasp Andricus kollari (Hartig, 1843), Synergus reinhardi Mayr, 1872 is a lethal inquiline in the larval chamber, while S. umbraculus (Olivier, 1791 ) develops in the outer wall of the gall and has no obvious negative effect on the gall-inducer (Askew 1984, Schönrogge et al. 1998, 1999, 2000). A marked feature of cynipid inquilines is that they are