Cuticular microstructures of abdominal tergites and sternites of <i>Cloeon</i> sp. (Ephemeroptera; Baetidae) during post-embryonic development

Abstract

The postembryonic changes of the external microstructure of the cuticle on the abdominal tergites and stemites of Cloeon sp. (Ephemeroptera:Baetidae) are described. An inventory of the structures as the aquatic nymph grows and becomes transformed into a terrestrial subimago and then an imago, is provided. It is found that sensillar diversity on nymphal tergites increases with development, but remains unchanged on the stemites. While nymphs and subimago possess various types of sensilla trichoidea, sensilla basiconica are apparent on the imaginal abdomen only. Furthermore, the scaled and spiny cuticle of the nymph becomes relatively smooth in the adult stages. The distinct changes which structure and distribution of the scales as well as marginal spines on the abdominal tergites and stemites of the nymphs undergo during development, must find a reflection in behavioural changes of the larvae. Finally, the taxonomic implications of the observed changes are discussed.

Apical antennal sensilla in nymphs of Libellula depressa (Odonata: Libellulidae)

“…Larval antennal sensilla of aquatic insects have been investigated only in some groups (see also review in Gaino & Rebora 1999a): Ephemeroptera (Gaino & Rebora 1996, 1998, 1999bGupta et al 1999), Plecoptera (Kapoor 1985(Kapoor , 1987(Kapoor , 1991, Diptera Culicidae (Zacharuk & Blue 1971a,b;Zacharuk et al 1971;Jez & McIver 1980), Diptera Simuliidae (Craig & Batz 1982), Diptera Psychodidae (Seifert et al 1990), Diptera Chaoboridae (Nicastro et al 1995).…”

Post-embryonic development of the lateral eye of <i>Cloeon</i> sp. (Ephemeroptera: Baetidae) as revealed by scanning electron microscopy

“…It is generally assumed that females, entering a swarm of males and performing offering flights, detect swarming males visually and that males (see above) also recognize females by sight. We do not know if that applies to all mayflies or whether there are some species in which mating can occur in darkness or with damaged eyesight; yet, on the basis of sexually dimorphic sensilla we do not want to rule out a pheromonal component totally (Gupta et al 1999). In the common scenario the male, as soon as it has spotted a female , pursues her and mates.…”

“…However, because of their unique features and unusual development they are also extremely valuable for functional and morphological studies. The present paper deals with the post-embryonic development of the eyes of a species of baetid mayfly that has already been the subject of an earlier SEM-study of the sensilla (Gupta et al 1999). The eyes, being photoreceptive organs, can be expected to perceive changes in brightness and to serve as instruments in both nymphs and adults for estimating form, shape, and distance.…”

Microsculpture and chaetotaxy of abdominal tergites of bark and ambrosia beetles (Coleoptera: Curculionidae, Scolytinae): morphology and nomenclature

“…These structures have not been analyzed in detail by this author, and a typology of microstructures has not been given. But we cannot ignore the fact that the more detailed description of tergal microstructures was given for Ephemeroptera (Gupta et al, 1999). In addition, two publications contain data on the microstructure of the abdomen and the thorax of Coccinelidae (Sun et al, 2018) and Tenebrionidae (Quian et al, 2015) with discussion of the functional purpose of these structures.…”