The structure and morphologic changes of antennae of Cyrtorhinus lividipennis (Hemiptera: Miridae: Orthotylinae) in different instars

Abstract

Cyrtorhinus lividipennis Reuter (Hemiptera: Miridae: Orthotylinae), including nymphs and adults, are one of the dominant predators and have a significant role in the biological control of leafhoppers and planthoppers in irrigated rice. In this study, we investigated the antennal morphology, structure and sensilla distribution of C. lividipennis in different instars using scanning electron microscopy. The antennae of both five different nymphal stages and adults were filiform in shape, which consisted of the scape, pedicel and flagellum with two flagellomeres. There were significant differences found in the types of antennal sensilla between nymphs and adults. The multiporous placodea sensilla (MPLA), basiconica sensilla II (BAS II), and sensory pits (SP) only occurred on the antennae of adult C. lividipennis of both sexes. Moreover, there was chaetica sensilla III (CHA III) only observed in males. Sixteen types of antennal sensilla were recorded altogether. They were microtrichia sensilla (MIC), three types of trichoidea sensilla (TRI I-III), three types of chaetica sensilla (CHA I-III), three types of basiconica sensilla (BAS I-III), two types of coeloconica sensilla (COE I and COE II), placodea sensilla (PLA), campaniform sensilla (CAM), MPLA, and SP. In the five different nymphal stages of C. lividipennis, the length of their antennae was significantly increased with the increase of the instar, as well as the number of the TRI II and TRI III. Moreover, sexual dimorphism usually occurred not only in the distribution (CHA III and SP) and the number of antennal sensilla (MIC, BAS II, TRI II, TRI III and MPLA), but also in the length of flagellum (F1 and F2). The possible functions of antennal sensilla are discussed. Those observations could contribute to a better understanding of the development of the olfactory system, and facilitate future studies on the antennal functions in C. lividipennis.

Teratological cases of the antennae in the family Aradidae (Hemiptera: Heteroptera)

“…Unfortunately, knowledge about the sensillar structures in most Heteroptera groups is very poor, which makes analyzing them quite difficult. Another problem is the various nomenclature used to describe each type of sensillum [e. g. 30,35,38,39 ]. Due to the limited research material as well as different research purpose, it was not decided to consider this issue in this paper.…”

Morphological characterization of antennae and antennal sensilla of Diaphorina citri Kuwayama (Hemiptera: Liviidae) nymphs

“…The whole bodies of the five different nymphal stages of D. citri were fixed in 2.5% glutaraldehyde at 4˚C for 24 h and post-fixed in 1% osmium tetraoxide for 2.5 h. The treatment process for the specimens including rinsing, dehydrating and drying was according to Yang et al [23]. Finally, the specimens were anchored on a holder using double-sided adhesive tape in the ventral and dorsal positions, sputter-coated with gold, examined and photographed either at 10 kV using an SEM (XL30, FEI, Holland and Nova Nano 430, FEI, Holland) or 25 kV by an SEM (JSM-6360LV, Japan).…”

Closer view of antennal sensory organs of two Leptoglossus species (Insecta, Hemiptera, Coreidae)

“…Several papers concern the antennal sensory organs of the blood-sucking Cimicidae [50][51][52] . Antennal sensilla have also been studied in a few species of families such as Miridae 40,[53][54][55][56] , Tingidae 57 , Lygaeidae 37 , Scutelleridae 58 . Within Coreoidea, sensory organs were examined in Rhopalidae 40 , Alydidae 37,59,60 , and two species of Coreidae (Coreus marginatus and Leptoglossus zonatus) 40,61,62 .…”