Morphology of the antennal sensilla of two species of Hoplopyga Thomson, 1880 (Coleoptera, Scarabaeidae, Cetoniinae)

Abstract

Antennal sensilla are important functional elements of sensory systems in insects. This study aimed to determine the morphology and structure of the sensilla of two species of the genus Hoplopyga. Adults of Hoplopyga liturata (Olivier, 1789) were collected in traps with sugarcane juice as an attractant. Thereafter, larvae of Hoplopyga albiventris (Gory and Percheron, 1833) were collected in mounds of termites (Cornitermes cumulans (Kollar, 1832) Isoptera). Then, they were reared in the laboratory for adult observations. Antennae of H. liturata and H. albiventris have sensilla chaetica, trichodea, placodea (type I and II), coeloconica (type I and II), and ampullacea (or pore). Females of H. liturata have a total of about 10657 sensilla and males have about 12512, whereas females of H. albiventris have about 16490 sensilla and the males 24565 sensilla. Sensilla placodea are predominant in the antenna of males and females of both species.

Antennal sensilla of two species of Gymnetis MacLeay, 1819 (Coleoptera: Scarabaeidae: Cetoniinae)

“…4A) and restricted the term sensilla basiconica to longer sensilla surrounded or not by a pit. The sensilla basiconica found on genera Cyclocephala (Dynastinae: Cyclocephalini; Saldanha et al, 2020;Nagamine et al, 2022) and Anomala (Rutelinae: Anomalini; Rodrigues et al, 2019) are not found in Cetoniinae genera of the tribe Gymnetini: Cotinis (described by Baker and Monroe, 2005), Gymnetis (by present study), and Hoplopyga (by Costa et al, 2021); and are also not found in other flower chafers as Osmoderma (Osmodermatini; by Zauli et al, 2016: sensilla basiconica sub-type 1 is here interpreted as a sensilla coeloconica variation) and Pachnoda (by Bengtsson et al, 2011).…”

“…With the development of the present study, the studies with the antennal sensilla of Cetoniinae were expanded to 20 species (Meinecke, 1975;Baker and Monroe, 2005;Zauli et al, 2016;Bohacz et al, 2020;Costa et al, 2021; present study): Cetonia aurata (Linnaeus, 1758), Cotinis nitida (Linnaeus, 1758), Epicometis hirta (Poda 1761), Gnorimus nobilis (Linnaeus, 1758), Gymnetis holosericea, Gymnetis rufilateris, Hoplopyga albiventris (Gory and Percheron, 1833), Hoplopyga liturata (Olivier, 1789), Leucocelis elegans, Mausoleopsis amabilis, Osmoderma eremita (Scopoli, 1763), Oxythyrea funesta (Poda 1761), Pachnoda ephippiata (Gerstaecker, 1867), Pachnoda marginata (Drury, 1773), Pachnoda interrupta (Olivier, 1789), Potosia affinis (Andersch, 1797), Potosia cuprea (Fabricius 1775), Protaetia morio (Fabricius, 1781), Trichius fasciatus (Linnaeus, 1758), and Valgus hemipterus (Linnaeus, 1758). Otherwise, the quantification of sensilla of males and females are known to (Costa et al, 2021; present study): Hoplopyga albiventris, Hoplopyga liturata, Gymnetis holosericea, and Gymnetis rufilateris.…”

“…These setae are designated here with sensilla chaetica, but other studies termed these setae as sensilla trichodea (as Bohacz et al, 2020). Despite the term used (see terminology in Material and Methods), the presence of this group of setae is a conspicuous character of Cetoniinae and part of Dynastinae (Bohacz et al, 2020;Costa et al, 2021), is inconspicuous to Rutelinae and part of Dynastinae (Cyclocephalini; Rodrigues et al, 2019;Saldanha et al, 2020;Nagamine et al, 2022), and is indistinct in Melolonthinae (Bohacz et al, 2020;Menis et al, 2021). In Rutelinae and Cyclocephalini, the outer side of proximal lamella has a sparse group of setae, and these setae are not evidently different from other setae present on lamellar edges (Rodrigues et al, 2019;Nagamine et al, 2022).…”

“…Some studies show that the phytophagous scarab beetles, sometimes named as Pleurosticti (including Cetoniinae, Dynastinae, Melolonthinae, Rutelinae, and others minor subfamilies), have some types of sensilla in their antennal lamellae (those lamellae together form the antennal clava or club), as sensilla placodea, basiconica, coeloconica, ampullacea (pores), chaetica, and trichodea (Romero-López et al, 2004;Shao et al, 2019;Saldanha et al, 2020). The sensilla subtypes and its amount is variable regarding different species and the sensilla distribution often show variation between males and females (Tanaka et al, 2006;Romero-López et al, 2010;Costa et al, 2021).…”

Antennal sensilla in Cyclocephala literata Burmeister, 1847 (Coleoptera: Scarabaeidae: Dynastinae)

“…An undetermined species of Cyclocephala studied by Bohacz et al (2020) was described with a "brush-like sensilla trichodea". Hair-like sensilla grouped in a brush-like structure (or "field of setae") occur in Dynastinae (Bohacz et al 2020) and at least in some Cetoniinae (Bohacz et al (2020) to Valgus hemipterus (Linnaeus, 1758); Costa et al (2021) to two species of Hoplopyga).…”