Galls induced by cynipid wasps of the genus Diplolepis (Hymenoptera: Cynipidae) on the roses of Canada's grasslands

Abstract

Abstract. Thirteen species of cynipid wasps of the genus Diplolepis induce structurally distinct galls on the three species of wild roses found on the grasslands of western Canada. Three species of Diplolepis gall the short rose, Rosa arkansana, in the Mixed Grassland and Moist Mixed Grassland ecoregions of southern Alberta and Saskatchewan, and eight species gall the common prairie rose, R. woodsii, throughout the prairie grasslands. Five species of Diplolepis gall the larger rose, R. acicularis, in more shaded regions such as the Aspen Parkland Ecoregion. This chapter outlines the life history strategy of Diplolepis and the manner by which these insects are well adapted to grassland conditions. Also described are the galls of each species, along with the component communities associated with them.Résumé. Treize espèces de cynipidés du genre Diplolepis engendrent la formation de galles structurellement distinctes sur trois espèces de rosiers indigènes des prairies de l'ouest du Canada. Trois de ces espèces de guêpes produisent des galles sur le rosier des prairies (Rosa arkansana) dans les écorégions des prairies mixes et des prairies mixtes humides du sud de l'Alberta et de la Saskatchewan, et huit autres s'attaquent au rosier de Woods (R. woodsii) dans l'ensemble de la région des prairies. Cinq espèces de Diplolepis engendrent des galles sur le rosier aciculaire (R. acicularis) dans les régions plus ombragées comme l'écorégion de la forêt-parc à trembles. Ce chapitre décrit les stratégies de survie des Diplolepis et la façon donc ces insectes se sont adaptés aux conditions caractéristiques des prairies. Il décrit également les galles produites par chacune de ces espèces, ainsi que les communautés qui leur sont associées.

Revision of Canadian Eurytomidae (Hymenoptera, Chalcidoidea) associated with galls induced by cynipid wasps of the genus Diplolepis Geoffroy (Hymenoptera, Cynipidae) and description of a new species

“…The emergence period of adults is synchronized with that of their host, which occurs soon after the immature galls appear such that the ovipositing females ( Fig. 1) can reach the chambers of developing galls in this narrow window of opportunity (Shorthouse 2010). Eurytomid eggs are brown to black, and with an elongated egg body, and a curved peduncle which may be used to attach the egg to the inside surface of the developing gall chambers or the body of its host ( Fig.…”

“…Members of the family Eurytomidae (Hymenoptera: Chalcidoidea) are one of the most common parasitoids associated with cynipid galls on roses in Canada, often comprising up to 40% of the component community (Shorthouse 2010). Bugbee (1951a, b) reported 12 species of Eurytoma Illiger and one species of Tenuipetiolus Bugbee known from galls of Diplolepis, and suggested that most species are monophagous.…”

“…Bugbee (1951a, b) reported 12 species of Eurytoma Illiger and one species of Tenuipetiolus Bugbee known from galls of Diplolepis, and suggested that most species are monophagous. Little is known about the host specificity of eurytomids in galls of the 14 species of Diplolepis found in Canada, but all species of Diplolepis are host to at least one species of Eurytoma (Shorthouse 2010, Zhang et al 2014.…”

“…Approximately 200 species of hymenopteran parasitoids are known from cynipid galls in Europe and North America, most of which are gall-specific (Csóka et al 2005). For instance, parasitoids associated with galls induced by Diplolepis Geoffroy, in particular the European species D. rosae L. (Stille 1984, Lázsló and Tóthmérész 2006, Lotfalizadeh et al 2007c, the North American species D. polita (Ashmead), D. nodulosa (Beuttenmül-ler) (Brooks and Shorthouse 1997, Shorthouse 1973, 2010, and Diplolepis fructuum (Rübsaamen) in Iran (Lotfalizadeh et al 2012) have been well studied. However, the taxonomy and ecology of many of these inquilines and parasitoids associated with Diplolepis are poorly known due to their small size and morphological conservatism (Shorthouse 2010).…”

“…Inquilines have lost their ability to induce galls, but still retain the ability to modify gall tissue (Brooks and Shorthouse 1997, Ronquist et al 2015, Pujade-Villar et al 2016. While entirely phytophagous, inquilines usually result in the death of inducers either through adult oviposition, or through competition for the same resources in the gall (Shorthouse 1973, 2010, Pujade-Villar et al 2016. Parasitoids associated with cynipid galls feed either internally or externally as the host continues to develop (koinobionts), or when development of the host has been arrested by stinging prior to oviposition as for idiobionts (Csóka et al 2005).…”