Fine structure of antennal sensilla of the spittlebug Philaenus spumarius L. (Insecta: Hemiptera: Aphrophoridae). I. Chemoreceptors and thermo-/hygroreceptors.
The meadow spittlebug, Philaenus spumarius (L.) (Hemiptera: Cercopoidea: Aphrophoridae), is a polyphagous species that transmits Xylella fastidiosa, a bacterium associated with "Olive Quick Decline Syndrome" in Southern Italy. In this study, the morphology and the ultrastructure of the antennal sensilla of P. spumarius were investigated. The antennae consist of three segments: a basal scape, a pedicel and a flagellum composed of a basal enlargement (ampulla) and a long segment (filament). The pedicel bears a single campaniform sensillum while the ampulla houses twelve coeloconic sensilla and three large basiconic sensilla. These latter sensilla show a smooth multiporous external cuticular wall and a total number of 27 sensory neurons per sensillum. The coeloconic sensilla belong to two morphologically distinct types: double-walled and single-walled sensilla. The sensory peg of the double-walled sensilla is smooth at the base and distally has a grooved cuticular surface with pores organized in spoke channels between each ridge. Three sensory neurons enter the lumen while at the basal level, before entering the peg, a fourth sensory neuron is found. The single-walled sensilla show an aporous thick cuticular wall and two sensory neurons entering the sensillar lumen, with a third neuron ending at the sensillum base.
Dipartimento Scienze Agrarie, Alimentari E Ambientali, Università Politecnica Delle Marche, via Brecce Bianche, Ancona, 60131, Italy.
Emanuele
E
Ranieri
Dipartimento Scienze Agrarie, Alimentari E Ambientali, Università Politecnica Delle Marche, via Brecce Bianche, Ancona, 60131, Italy.
Sara
S
Ruschioni
Dipartimento Scienze Agrarie, Alimentari E Ambientali, Università Politecnica Delle Marche, via Brecce Bianche, Ancona, 60131, Italy.
Paola
P
Riolo
Dipartimento Scienze Agrarie, Alimentari E Ambientali, Università Politecnica Delle Marche, via Brecce Bianche, Ancona, 60131, Italy.
Nunzio
N
Isidoro
Dipartimento Di Scienze Agrarie, Alimentari E Ambientali, Università Degli Studi Di Perugia, Borgo XX Giugno 74, Perugia, 06121, Italy. Electronic address: roberto.romani@unipg.it.
Roberto
R
Romani
D000818:Animals; D057506:Arthropod Antennae / Q000648:ultrastructure*; D006430:Hemiptera / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D058618:Sensilla / Q000648:ultrastructure
Bacteria vectors; Coeloconic sensilla; Functional anatomy; Olfactory sensilla; Ultrastructure