A comprehensive list of all known host plant species utilised by the Meadow Spittlebug (Philaenus spumarius (L.)) is presented, compiled from published and unpublished sources. P. spumarius feeds on 1311 host plants in 631 genera and 117 families. This appears, by a large margin, to be the greatest number of host species exploited by any herbivorous insect. The Asteraceae (222 species) and Rosaceae (110) together account for 25% of all host species. The Fabaceae (76) and Poaceae (73), are nearly tied for third and fourth place and these four families, combined with the Lamiaceae (62), Apiaceae (50), Brassicaceae (43) and Caprifoliaceae (34), comprise about half of all host species. Hosts are concentrated among herbaceous dicots but range from ferns and grasses to shrubs and trees. Philaenus spumarius is an “extreme polyphage”, which appears to have evolved from a monophage ancestor in the past 3.7 to 7.9 million years. It is also the primary European vector of the emerging plant pathogen Xylella fastidiosa. Its vast host range suggests that it has the potential to spread X. fastidiosa among multiple hosts in any environment in which both the spittlebug and bacterium are present. Fully 47.9% of all known hosts were recorded in the Xylella-inspired BRIGIT citizen science P. spumarius host survey, including 358 hosts new to the documentary record, 27.3% of the 1311 total. This is a strong demonstration of the power of organized amateur observers to contribute to scientific knowledge.

Behavioral manipulation (BM) is a multimodal control approach based on the interference with the stimuli mediating insect perception and interaction with the surroundings. BM could represent a win–win strategy for the management of vector-borne plant pathogens as the bacterium Xylella fastidiosa, since it could reduce the number of vectors alighting on host plants and, consequently, the chances for transmission to occur. In this review, we summarized current knowledge and highlighted gaps in information on (i) how insect vectors of X. fastidiosa in general, and more specifically the meadow spittlebug Philaenus spumarius, locate and accept the host plant; and (ii) how behavioral manipulation techniques could be applied to disrupt the vector–host plant interaction. Finally, we discussed how diverse BM strategies could be combined with other integrated pest management tools to protect olive groves from inoculation with the fastidious bacterium.

Over most of its range populations of the spittlebugProsapia ignipectus(Fitch) (Hemiptera: Cercopidae) are monomorphic for black dorsal coloration. At the far northeastern margin of the species range in Maine, a cluster of populations is monomorphic for the presence of traverse orange dorsal lines against a black background. The narrow gap separating monomorphic black and monomorphic lined populations is less than 10 km wide, shows no evidence of a hybrid zone, and is without consequential physical barriers or ecological breaks. This sharp and unexpected division of color forms seems to have persisted for at least 90 years. It appears to be the sharpest divide ever recorded between geographically adjacent populations monomorphic for alternative aposematic color forms. About 45 kilometers to the southwest of this dividing line, three closely situated populations, surrounded by monomorphic black populations, are polymorphic for the two color forms. These observations are at variance with several expectations for aposematic species: (1) that local populations will be monomorphic for warning coloration, (2) that adjacent populations monomorphic for different local color forms will be linked by populations with mixed or hybrid forms, and (3) that geographic boundaries between contrasting aposematic color forms should be temporally unstable.

Actinorhizal plants are major hosts for many spittlebugs, particularly species of the genera Clastoptera and Aphrophora. World host records indicate that at least 20 spittlebug species have primary associations with at least 17 actinorhizal hosts in the genera Alnus, Casuarina, Ceanothus, Comptonia, Elaeagnus, and Myrica. The highly polyphagic spittlebug, Philaenus spumarius (L.), has also been observed in association with Hippophaë and Coriaria. Several other spittlebugs have minor associations with actinorhizal hosts.Key words: actinorhizal plant, spittlebug, host, nitrogen-fixing.