Sensory structures on the antenna of soldier and worker castes of the termite species Odontotermes parvidens (Termitidae: Isoptera: Blattaria)

Abstract

Odontotermes parvidens is a commonly found important pest species of termite that primarily feed on a range of cellulosic sources. In termites, communication among the nestmates is the basis of all their daily activities and the sensory structures present on the sensory appendages play a crucial role in different social behaviors perceiving and processing various signals of the nestmates and external environments. So, it is essential to understand in detail their sensory structures in order to understand the sensory system of the species O. parvidens. Thus, we have studied the antenna which is one of the primary sensory appendages of both soldier and worker individuals of the species to elucidate various antennal sensory structures and their distribution using scanning electron microscopy. Based on the morphological features of various sensilla, we observed seven types of sensilla as sensilla chaetica (subtypes I, II, III, and IV), sensilla trichodea (subtypes I and II), sensilla trichodea curvata (subtypes I and II), sensilla basiconica, sensilla capitula, Böhm bristles, and sensilla campaniformia (subtypes I and II) along with numerous glandular pores on the antenna of soldier and worker castes. We have also discussed the putative functions of all the sensilla observed based on their external morphology and distributional characteristics on the antenna of soldier and worker castes of the species O. parvidens. Furthermore, the abundance of sensillar types on the antenna of both the castes has also been discussed.

Scanning electron microscopy study of the antennal sensilla of cob borer, Stenachroia elongella (Lepidoptera: Pyralidae)

“…Specialized sensilla on the antennae of insects, which can detect various stimuli are used in the reception of host, mate and food (Onagbola et al, 2008; Schneider, 1964). Morphology and structure studies of sensilla are the basement of function study, and the antennal sensilla of many insects have been described by using scanning electron microscopy (Das et al, 2021; Faucheux, 1985; Fu et al, 2012; Gao et al, 2007; Roh et al, 2020; Wang et al, 2010; Zhang et al, 2016; Zhu et al, 2017). Previous studies have also characterized the antennal sensilla of Pyralidae families of Lepidoptera, Ephestia kuehniella (Anderson & Hallberg, 1990), Homoeosoma nebulella (Faucheux, 1991), Ostrinia nubilalis (Hallberg et al, 1994), Zamagiria dixolphella (Castrejon Gomez et al, 2003), Cnaphalocrocis medinalis (Sun et al, 2011), Dioryctria rubella (Xu et al, 2021).…”

“…Specialized sensilla on the antennae of insects, which can detect various stimuli are used in the reception of host, mate and food (Onagbola et al, 2008;Schneider, 1964). Morphology and structure studies of sensilla are the basement of function study, and the antennal sensilla of many insects have been described by using scanning electron microscopy (Das et al, 2021;Faucheux, 1985;Fu et al, 2012;Gao et al, 2007;Roh et al, 2020;Wang et al, 2010;Zhang et al, 2016;Zhu et al, 2017).…”