Morphology and biological notes of Macrosiagon octomaculata (Gerstaecker) triungulinid and a summary of the knowledge on immature stages of the genus (Ripiphoridae)

Abstract

Species of Macrosiagon Hentz are known to be wasp and bee parasitoids. Here, we present information on Macrosiagon octomaculata (Gerstaecker, 1855), including eggs and triungulinids, found on Paepalanthus polyanthus (Bong.) Sano (Eriocaulaceae) blooming in restinga habitat on Santa Catarina Island, South Brazil. This is the first record of an Eriocaulaceae species playing an important role in the Macrosiagon bionomics and the first accurate record of Ripiphoridae for southern Brazil, Santa Catarina state. In the study area, P. polyanthus attracted an inordinate number of insect species and one Thynnidae wasp was captured with a triungulinid on its wing. Eggs and triungulinids were also found on one plant of P. polyanthus and associated with M. octomaculata. We provide descriptions of the female reproductive organs as well as the morphology of the triungulinid of M. octomaculata. A detailed examination of the triungulinid revealed novelties that complement information from previous publications regarding the Ripiphoridae. We also compare triungulinids of M. octomaculata with those of other species, and provide a table summarizing comparative characters. Finally, we provide a table with current information on the recorded host species and immatures of Macrosiagon.

Updated catalog of the Chilean wedge-shaped beetles (Coleoptera: Ripiphoridae) with the first records of Macrosiagon flavipennis (LeConte) in Chile

“…The genus Macrosiagon is the richest genus of wedge-shaped beetles and is widely distributed worldwide (Falin, 2004). Species of Macrosiagon have several hosts recorded from aculeate wasps (Crabronidae, Pompilidae, Scoliidae, Sphecidae, Tiphiidae, Thynnidae, Vespidae) to solitary bees like Apidae, Halictidae and Megachilidae (Ulysséa & Albertoni, 2020). Here, we report the presence of M. flavipennis in northern Chile, a species otherwise commonly found in the southern USA, Mexico and Caribbean Islands, and previously recorded from Argentina (sensu Vaurie, 1955).…”

“…Natural history of the Chilean Ripiphoridae remains unknown (Elgueta & Arriagada, 1989). Although other countries have recently generated important contributions on the hosts of some Macrosiagon species (Barreda & Ayala Landa, 2020;Ulysséa & Albertoni, 2020), further fieldwork is needed to better understand the biology of these elusive beetles. Recently, Cid-Arcos & Ramírez-Cuadros (2022) described the biology of Nemognatha nigrotarsata (Fairmaire & Germain, 1861), including the first record of triungulin of this species parasitizing primarily on Diadasia sp.…”

“…Ripiphoridae is phylogenetically near to the Mordellidae beetle family, discarding their relationship with Meloidae (Batelka et al, 2016). Adults are frequently found feeding on flowers of different families (Ulysséa & Albertoni, 2020), whereas larvae are characterized by parasitizing (both as ectoparasitoids and endoparasitoids) different hosts, such as beetles (Pelecotominae and Hemirhipidiinae) or cockroaches (some Ripidiinae species), although Ripiphorinae larvae develop in Hymenoptera nests (Auko et al, 2014;Ulysséa & Albertoni, 2020).…”

“…The Neotropical Region only contains twelve genera (Ancholaemus Gerstaecker, 1855b;Elytroxystrotus Manfrini de Brewer, 1963; Ivierhipidius Barclay, 2015;Macrosiagon Hentz, 1830;Micholaemus Viana, 1971;Neorrhipidius Viana, 1958;Pirhidius Besuchet, 1956;Quasipirhidius Zaragoza-Caballero, 1991;Quasiriphidius Zaragoza-Caballero, 1991;Ripiphorus Bosc, 1791;Trigonodera Dejean, 1834, andZaragozapirhidius Vega-Badillo et al, 2022) and one-third of the extant species approximately (Costa, 2000;Barclay, 2015;Batelka & Chaboo, 2015). Some countries such as Peru or Brazil have recently published updated catalogs, incorporated new records, summed new species and new information on their biology (Barclay, 2015;Batelka & Chaboo, 2015;González & Juárez, 2016;Ulysséa & Albertoni, 2020). Ripiphoridae in Chile has been scarcely collected and so far, represented by two genera and three species: Macrosiagon gayi (Gerstaecker, 1855b); Macrosiagon vittata (Erichson, 1847), and Ripiphorus valdivianus (Philippi, 1861) (Elgueta & Arriagada, 1989;Elgueta, 2000;Falin, 2004).…”

Phylogeographic and Phylogenetic Notes on Iberian Ripiphoridae (Coleoptera)

“…Their immature stages are parasitoids of a wide range of hosts. Namely, Pelecotominae Seidlitz, 1875 and Hemirhipidiinae Heller, 1921 larvae develop in wood-boring beetles (e.g., Ptinidae Latreille, 1802 and Cerambycidae Latreille, 1802); Ripiphorinae Laporte, 1840 are parasitoids of aculeate Hymenoptera, while Ripidiinae Gerstaecker, 1855 parasitize mainly Blattodea (e.g., Falin 2002, Batelka 2010, Batelka et al 2016, Ulysséa and Albertoni 2020, Li et al 2022. Investigating the life histories of Riphoridae is challenging.…”