Table 1.
Terminology used with probable functions, morphological characteristics and measurements, and distribution of antennal sensilla in Lycorma delicatula.
Fig 1.
General view of the three-segmented antenna of Lycorma delicatula nymphal instars and adults.
(A–D) Full antenna first to fourth instar, respectively. (E–F) Full antenna in adult female and male, respectively. Scale bars: A = 90 μm; B–F = 100 μm. Abbreviations: f, antennal flagellum; p, antennal pedicel; s, antennal scape.
Fig 2.
Details of the antenna of the first nymphal instar of Lycorma delicatula.
(A) General view of the antenna, showing the distribution of sensilla on antennal surface. (B) Basal bulb of antennal flagellum with LPO 1 and SPO 1. (C–D) LPO1 and opening of Bourgoin's organ. (E–F) SPO 1, showing the multiporous folds and cuticular denticles with smooth surface. Scale bars: A = 100 μm; B = 25 μm; C = 20 μm; D = 20 μm; E = 15 μm; F = 10 μm. Abbreviations: AA, apical arista of antennal flagellum; BB, basal bulb of antennal flagellum; BO, Bourgoin’s organ; CD, cuticular denticles; Ch 1, sensillum chaeticum type I; f, flagellum; LPO1/SPO1, large/small plate organ type I; p, pedicel; s, scape.
Fig 3.
Details of the antenna of the second nymphal instar of Lycorma delicatula.
(A) General view of the antenna, showing the distribution of sensilla on antennal surface. (B–C) Basal bulb of antennal flagellum, LPO1 and SPO1. (D) SPO1 with an indented and raised wall. (E–F) Plaque organ type II on the pedicel, showing the multiporous folds and ridged sclerotized denticles. Scale bars: A = 100 μm; B and C = 25 μm; D and E = 15 μm; F = 10 μm. Abbreviations: AA, apical arista of antennal flagellum; BB, basal bulb of antennal flagellum; CD, cuticular denticles; Ch 1, sensillum chaeticum type I; CW, encircling walls; f, flagellum; FO, folds; p, pedicel; PO 1, plate organs type I; PO 2, plate organs type II; s, scape; SD, sclerotized denticles.
Fig 4.
Details of the antenna of the third nymphal instar of Lycorma delicatula.
(A) General view of the antennae, showing the distribution of sensilla on antennal surface. (B) Basal bulb of antennal flagellum, LPO 1 and SPO1. (C) LPO 1 on the anterior faces of the antenna. (D) SPO1 on the posterior face of the antenna. (E) PO 2 of the pedicel. (F) Multiporous surface of PO2 lobes. Scale bars: A = 150 μm; B = 25 μm; C = 15 μm; D = 10 μm; E = 20 μm; F = 2 μm. Abbreviations: AA, apical arista of antennal flagellum; BB, basal bulb of antennal flagellum; CD, cuticular denticles; CW, encircling walls; f, flagellum; FO, multiporous folds; p, pedicel; PO1, plaque organ type I; PO2, plaque organ type II; s, scape; SD, sclerotized denticles.
Fig 5.
Details of the antenna of fourth nymphal instar Lycorma delicatula and in adults.
(A) General view of fourth nymphal instar antenna, showing the distribution of sensilla on antennal surface. (B) Basal bulb of antennal flagellum in fourth instar, PO 1 are absent. (C) PO 2 on the pedicel of the fourth instar, some pores (po) are visible. (D) General view of adult antenna, showing the distribution of sensilla on antennal surface. (E) Basal bulb of adult antennal flagellum. (F) PO 2 in adult pedicel. Scale bars: A = 250 μm; B = 25 μm; C = 20 μm; D = 250 μm; E = 50 μm; F = 25 μm. Abbreviations: AA, apical arista of antennal flagellum; BB, basal bulb of antennal flagellum; BO, Bourgoin’s organ; CD, cuticular denticles; f, flagellum; FO, folds; p, pedicel; PO 2, plaque organ type II; s, scape; SD, sclerotized denticles.
Fig 6.
Bourgoin’s organ and campaniform sensilla on the antennae of Lycorma delicatula.
(A) Bourgoin’s organ aperture on basal bulb of flagellum and in boxes sensillum coeloconicum inside. (B) Ca 1 on apex of antennal pedicel. (C) Ca 2 on antennal pedicel. (D) Ca 2 on antennal scape. Scale bars: A = 5 μm (2 μm in box); B = 50 μm (5 μm in box); C = 10 μm; F = 5 μm. Abbreviations: BO, Bourgoin’s organ; Ca 1, campaniform sensillum type I; Ca 2, campaniform sensillum type II with a median pore.
Fig 7.
Three types of chaetica sensilla on the antennae of Lycorma delicatula.
(A)–(B) Ch1 on the pedicel, with length varying from 20 to 35.5 μm. (C) Magnification of Ch1 base. (D) CH2L and (E) CH2 on the pedicel, the box in (E) showing the magnification of socket base and convergent ridges. (F) Magnification of Ch2L socket base and mostly parallel ridges. (G) Ch3 on antennal scape. (H) Magnification of longitudinally ridged shaft. (I) Magnification of Ch3 socket base. Scale bars: A, C, H = 2.5 μm; B, F, I = 5 μm; D = 15 μm; E = 10 μm (2.5 μm in the box); G = 20 μm. Abbreviations: Ch 1, 2, 3, sensilla chaetica type 1, 2, 3.
Fig 8.
Distribution of sensilla on first to third instar nymphal antennae of Lycorma delicatula.
(A–C) First–third instar nymphal antennae, respectively. Abbreviations: FA anterior face; FD dorsal face; FP posterior face; FV ventral face.
Fig 9.
Distribution of sensilla on forth instar nymphal and adult antennae of Lycorma delicatula.
(A) Forth instar nymphal antennae (B) Male antenna. (C) Female antenna. Abbreviations: FA anterior face; FD dorsal face; FP posterior face; FV ventral face.
Fig 10.
Proportional representation of sensory surface of Lycorma delicatula antennae in nymphal instars and adults (for one antenna, in μm2).
Abbreviations: 1, dorsal face; 2, anterior face; 3, ventral face; 4, posterior face of the antenna; F, female; M, male; N2 –N4, second to fourth instar.
Fig 11.
Development of sensory surface of plate organs on antennae in nymphal instars and adults (for one antenna, in μm2).
Abbreviations: FA, anterior face; FD, dorsal face; FP, posterior face; FV, ventral face; TSS, total sensory surface.
Fig 12.
Diagram of antennal plate organs and behaviours, showing their evolution and possible functions in one cycle of Lycorma delicatula.
Sensory surfaces for flagellar plate organs type I (PO1) in red (scale 103 μm2), and for pedicel plate organs type II 2 (PO2) in blue (scale 106 μm2). PO2 in N2 added for comparison with PO1 at same scale (doted line). Abbreviations: DF, VF: dorsal, ventral face of antenna; SS sensory surface.