Antennal Sensilla in Vespidae: A Comparison Between a Diurnal and a Nocturnal Polistinae Wasp

Abstract

Social wasps have a widespread Neotropical distribution and are important pollinators and biological control agents for pest insects. The foraging activity of wasps is influenced by biotic and abiotic factors that are detected by the antennal sensilla that vary according to species, sex, caste, and environmental conditions. This study compares the types and quantities of antennal sensilla with a scanning electron microscope between the nocturnal Apoica flavissima and the diurnal Polistes simillimus wasps. Six types of sensilla were found in the antennae of both species: placoid, coeloconic, basiconic-type 1, basiconic-type 2, trichoid-type 1, and trichoid-type 2. Sensilla chaetica were found only in the scape and pedicel of A. flavissima. In the nocturnal wasp, there are 19,132.27 ± 1,247.72 sensilla in the left and 17,746.46 ± 1,477.46 in the right antennae, whereas in the diurnal wasp 14,936.72 ± 1,271.69 in the left and 16,090.82 ± 1,345.3 in the right antennae. A. flavissima has a longer antennal length and number of sensilla than P. simillimus. The higher number of antennal sensilla in the nocturnal wasp is not linked with the antennal size. The association of antennal sensilla functions with ecological and behavioral factors of A. flavissima and P. simillimus are discussed.

Subtle morphological changes in the visual and antennal sensory system of bees and wasps across an urbanisation gradient

“…PO are round pores on the surface of the flagellomere, ST are quite long and perpendicular to the antennal surface, with a sharp end, SP are plates with rounded edges shaped into grooves, with the surface slightly depressed in relation to the body wall level, while SB are straight hairs with a blunt tip and a single pore, which sometimes may not be visible. We did not distinguish further sub-types of ST [21][22][23][24] as these are not relevant for the purpose of this work. While the PO are known to include not only thermo-hygro receptors but also CO 2 receptors, the relative role of these stimuli is still unclear for these sensilla [48][49][50] .…”

“…In bees and wasps, there are several types of antennal sensilla. Pit organs (PO) which have a thermal-(cold sensitive), hygro-and/or CO 2 -detecting function, sensilla placoidea (SP) and basiconica (SB) which have an olfactory/gustatory function, and sensilla trichoidea (ST) which have either an olfactory, gustatory or mechanoreceptor function, depending on the sub-type (see [21][22][23][24] ).…”

“…Much effort has been devoted to understanding the evolution of sensory systems in insects, and we now have a large bulk of evidence that both visual and antennal apparatus differ between species and between sexes within species in function of the variability of life-history traits such as flying time, food specialisation, foraging strategies, mating tactics and social behaviour 18,20,[22][23][24][25][26][27][28][29] . More relevant to the present study, insect sensory system was also found to change morphologically across environmental gradients.…”

Morphology and Distribution of Antennal Sensilla on Spodoptera frugiperda (Lepidoptera: Noctuidae) Larvae and Adults

“…Insect antennae are equipped with various sensilla that serve important functions in different behaviors such as foraging, courtship, and oviposition [10,11]. Numerous studies describe the antennal sensilla of multiple insect species, including Coleoptera [12,13], Hymenoptera [14], and Hemiptera [15]. However, research on the antennal sensilla of Lepidoptera larvae is limited compared to that of adults.…”