Relating antennal sensilla diversity and possible species behaviour in the planthopper pest Lycorma delicatula (Hemiptera: Fulgoromorpha: Fulgoridae)

Abstract

Antennal sensory units in nymphs and adults of the spotted Lanternfly, Lycorma delicatula (White) (Hemiptera: Fulgoromorpha: Fulgoridae), an economically important plant pest, are studied with scanning electron microscopy. Sensilla trichodea / chaetica type recognition is based on their external morphology and ratio of their size to diameter. The flagellum Bourgoin’s organ is a complex sensory unit with 2–3 internal sensilla coeloconica. During nymphal stages, the sensory surface available for a chemoreceptive function particularly increases with the number and size of sensilla placodea on the antennal pedicel. From first to fourth instar and to adult males and females, plate organ sensory surface is estimated to increase respectively by 33x, 68x and 125x (= 2.72 mm2 and 5.02 mm2 respectively for males and females). The most important increase (5x) occurs between second and third instar. In parallel, a distinctive pair of plate organs on the flagellum decreases in size from first to third instar, and disappears. Sexual dimorphism occurs in sensilla placodea in adults. Diversity, disparity and evolution of nymphal sensilla, and their sexual dimorphism in adults are discussed in the context of the species and planthopper behaviour.

Functional morphology of antennae and sensilla of Hippodamia variegata (Coleoptera: Coccinellidae)

“…Moreover, the incidence, density, types and distribution of sensilla and other aspects that closely related to their function may also greatly differ among different species [12][13][14][15][16]. These remarkable differences of sensory equipment in antennae have many potential values for taxonomic and ecological research and in behavior analyses [17][18][19].…”

Antennal Morphology and Sexual Dimorphism of Antennal Sensilla in Callitettix versicolor (Fabricius) (Hemiptera: Cercopidae)

“…L. striatellus (Delphacidae), minor sexual dimorphism occurs in the number of sensilla (usually slightly more in the female) but not in the arrangement of sensilla types [ 61 ]. Sexual dimorphism occurs in the olfactory sensilla placodea in adults of Lycorma delicatula (White) (Fulgoridae); in this case with a significantly higher number and size of sensilla placodea in females than males [ 9 ].…”

“…Antennae play a crucial role in insect behavior, including host location and recognition, as well as mating behavior [ 3 , 4 , 5 , 6 , 7 , 8 ]. Moreover, the form of the antenna varies considerably depending on its precise function and the remarkable difference on sensory equipment, which has the potential value for taxonomic and phylogenetic analyses [ 9 ].…”

“…Exterior variation of the different types of sensilla and their distribution on the pedicel and flagellum in the Hemipteran infraorder Fulgoromorphan (planthoppers), have received more attention, as these structures have a potential value in taxonomic and phylogenetic analysis [ 9 , 22 , 23 , 24 , 25 , 26 ]. Cercopoid antennae also offer an abundance of structures that provide excellent taxonomic and phylogenetic characters [ 1 , 17 ].…”

PM 7/144 (1) Lycorma delicatula

“…The antennae consist of three segments: scape, pedicel and flagellum. Sensory plate organs are present in great numbers on the pedicel (Wang et al ., 2018).…”