Biorhiza pallida (Olivier, 1791)

Shachar, Einat, Melika, George, Inbar, Moshe & Dorchin, Netta, 2018, The oak gall wasps of Israel (Hymenoptera, Cynipidae, Cynipini) - diversity, distribution and life history, Zootaxa 4521 (4), pp. 451-498 : 471

Biorhiza pallida (Olivier, 1791)

Host plants. Israel: Q. boissieri . Elsewhere: several oak species from section Quercus .

Life history. The sexual generation induces multi-chambered, irregularly spherical, soft and spongy galls, 15– 30 mm in diameter, light brown when mature ( Fig. 22 ). The asexual generation develops in multi-chambered galls in the roots.

Phenology. Galls of the sexual generation appear shortly after bud burst and mature through May and June. In Israel adults emerge in May, whereas in Southern Northern Europe they emerge at the end of May or in late June, respectively. Galls of the asexual generation take two years to mature, and complete their developement in the winter of their second year. The wingless females of the asexual generation emerge in the winter or very early spring, climb up the tree, and lay their eggs on shoots ( Melika 2006b).

Distribution. Israel: Rare; known only from Mt. Kahal. Only the sexual generation was found in the present study, as root galls were not surveyed. Elsewhere: A widespread and often common species known from Europe, Northwestern Africa, east to Transcaucasia, Turkey and Iran. Data on the distribution in the Far East of Russia appears to be erroneous due to misidentification with another species - B. nawai (Ashmead) ( Melika 2012) .

Figures

FIGURES 17–22. Galls on Quercus boissieri. 17. Andricus coriariformis, asexual generation; 18. Andricus moreae, asexual generation; 19. Andricus sp. 1, asexual generation; 20. Andricus sternlichti, asexual generation; 21. Andricus megatruncicolus, asexual generation; 22. Biorhiza pallida, sexual generation.