A case of ecological specialization in ladybirds:Iberorhyzobius rondensis(Coleoptera: Coccinellidae), potential biocontrol agent ofMatsucoccus feytaudi(Hemiptera: Matsucoccidae)

Abstract

Specialization is an important attribute of a biological control agent. The maritime pine bast scale, Matsucoccus feytaudi Ducasse (Hemiptera Matsucoccidae), is an invasive species in Southeast France and the North of Italy. Iberorhyzobius rondensis Eizaguirre (Coleoptera: Coccinellidae), is a recently described ladybird species. Both adults and larvae are predaceous, feeding on egg masses of M. feytaudi, and are strongly attracted to M. feytaudi's sex pheromone. To evaluate the potential of I. rondensis as a biocontrol agent of the scale, we studied its niche breadth and prey range with emphasis on pine forests and hemipterans as tested prey. In this study, I. rondensis was found to achieve complete development only when fed on M. feytaudi egg masses (92.9% survival) and an artificial prey: eggs of Ephestia kuehniella Zeller (27.6% survival). From the 2nd instar onwards, complete development could be achieved using other prey species, although larvae had significantly higher mortality and slower development. In choice tests, M. feytaudi was the preferred prey. Surveys of the ladybird populations in the Iberian Peninsula revealed that it was found exclusively on Pinus pinaster Aiton, the sole host of M. feytaudi. The unusual specialization of I. rondensis, among other predaceous ladybirds, makes it an appropriate candidate for classical biological control of M. feytaudi.

Niche width and niche specialization in four species of ladybirds (Coleoptera: Coccinellidae) co-occurring in the same habitat

“…Our study showed that the habitat specialists could temporarily switch to preying on invertebrates that are unsuitable or disregarded by competitors. Close habitat and prey specializations, as reported for Iberorhyzobius rondensis that exclusively occurs on Pinus pinaster and preys on Matsucoccus feytaudi (Tavares et al, 2014), are probably very rare among predatory ladybirds. Table S1.…”

An annotated checklist of ladybeetle species (Coleoptera, Coccinellidae) of Portugal, including the Azores and Madeira Archipelagos

“…Comments. This is an endemic species of the Iberian Peninsula, associated with maritime pine forests, and is a specialist predator of the maritime pine bast scale, Matsucoccus feytaudi Ducasse (Tavares et al 2014;Tavares et al 2015a;Tavares et al 2015b). Adults and mostly larvae were shown to be attracted by the sex pheromone of their prey (Branco et al 2006).…”

Reproductive Interference between Native and Introduced Lady Beetles (Coleoptera: Coccinellidae) in Puerto Rico

“…Lady beetles, ladybugs, or ladybird beetles (Coccinellidae) and their larvae feed on soft-bodied arthropods such as aphids, mealybugs, scales, whiteflies (Hemiptera), and mites (Arachnida) (Obrycki and Kring 1998), among others. Because of their diet, they are widely used as biocontrol agents in diverse ecosystems from agricultural to forests (Obrycki and Kring 1998;Tavares et al 2014). In Puerto Rico, the lady beetle fauna consists of 53 described species, seven of which have been introduced as biological control agents (Segarra-Carmona et al 2021).…”