Plagiotrochus razeti Barbotin 1985

Plagiotrochus razeti Barbotin, 1985

Host plants. Israel: Q. calliprinos. Elsewhere: Q. ilex.

Life history. Both the sexual and asexual generations are known but in Israel only the branch galls of the asexual generation were found. These constitute 10–35 mm long globular to elongate, multi-chambered swellings of the branch (Fig. 73). The larval chambers are arranged in a circle around at the gall circumference. The sexual generation induces single-chambered galls in lateral and terminal buds and in catkins, sometimes in aggregations.

Phenology. In Iberia, galls of the asexual generation develop in summer and adults emerge from them in December-January. Galls of the sexual generation develop in May and adults emerge at the end of that month (Nieves-Aldrey 2001).

Distribution. Israel: Pa’ar cave, Tivo'n, Mt. Carmel. Elsewhere: Iberian Peninsula, France.

Comments. The three females we reared from galls of the asexual generation run to P. razeti in available keys (Nieves-Aldrey 2001) and their comparison to voucher specimens of P. razeti from Iberia, deposited in the PHMB, suggested that they belong to that species. Galls of the asexual generation resemble those of Plagiotrochus gallaeramulorum from Europe but the larval chambers in the latter are arranged along the longitudinal axis of the gall rather than radially. Sternlicht attributed these galls to the asexual generation of Plagiotrichus kiefferianus, a species that was since synonymized with Plagiotrochus gallaeramulorum (Pujade-Villar 2005). We consider this species to be distinct from Plagiotrichus gallaeramulorum due to the different structure of the galls.