Larvae and Nests of Aculeate Hymenoptera (Hymenoptera: Aculeata) Nesting in Reed Galls Induced by Lipara spp. (Diptera: Chloropidae) with a Review of Species Recorded. Part II.

Abstract

The ability of aculeate Hymenoptera to utilize wetlands is poorly understood, and descriptions of their nests and developmental stages are largely absent. Here we present results based on our survey of hymenopterans using galls induced by Lipara spp. flies on common reed Phragmites australis in the years 2015–2016. We studied 20,704 galls, of which 9,446 were longitudinally cut and the brood from them reared in the laboratory, while the remaining 11,258 galls reared in rearing bags also in laboratory conditions. We recorded eight species that were previously not known to nest in reed galls: cuckoo wasps Chrysis rutilans and Trichrysis pumilionis, solitary wasps Stenodynerus chevrieranus and Stenodynerus clypeopictus, and bees Pseudoanthidium tenellum, Stelis punctulatissima, Hylaeus communis and Hylaeus confusus. Forty five species of Hymenoptera: Aculeata are known to be associated with reed galls, of which 36 make their nests there, and the other are six parasitoids of the family Chrysididae and three cuckoo bees of the genus Stelis. Of these species, Pemphredon fabricii and in southern Europe also Heriades rubicola are very common in reed galls, followed by Hylaeus pectoralis and two species of the genus Trypoxylon. We also found new host-parasite associations: Chrysis angustula in nests of Pemphredon fabricii, Chrysis rutilans in nests of Stenodynerus clypeopictus, Trichrysis pumilionis in nests of Trypoxylon deceptorium, and Stelis breviuscula in nests of Heriades rubicola. We provide new descriptions of the nests of seven species nesting in reed galls and morphology of mature larvae of eight species nesting in reed galls and two parasitoids and one nest cleptoparasite. The larvae are usually very similar to those of related species but possess characteristics that make them easy to distinguish from related species. Our results show that common reeds are not only expansive and harmful, but very important for many insect species associated with habitats dominated by this plant species.

Description of mature larvae and ecological notes on Gasteruption Latreille (Hymenoptera, Evanioidea, Gasteruptiidae) parasitizing hymenopterans nesting in reed galls

“…In the present study, we recorded G. nigrescens as abundant in nests of Heriades rubicola, a small bee of the same family as H. leucomelana. This species is spreading in Europe from south to north and makes its nests especially in reed galls and stalks (Astapenková et al 2017;Bogusch et al 2017). As H. rubicola belongs to the same family as the previously documented G. nigrescens host, H. leucomelana, and as H. rubicola uses the same nesting resource, the reed galls, it is likely that the use of H. rubicola as a host of G. nigrescens is a consequence of host switch that occurred only following the recent expansion of H. rubicola to the north (Cross and Notton 2017).…”

“…Also, the records on the hosts of the families Crabronidae and Vespidae published previously by several authors are unlikely -we recorded nests of crabronid species Pemphredon fabricii with larvae of Gasteruption but they were probably not parasitizing larvae of this species. Though it is common that two or more species occupy one reed gall (Bogusch et al 2015;Astapenková et al 2017), it is more probable that Gasteruption in these cases parasitized larvae of some bee species in the rest of the nest and destroyed all the nest remnants.…”

“…We collected from 50 to 1000 of over-one-year old galls at each locality. These galls were partly reared in the laboratory in special rearing sacs, the majority of them were longitudinally cut and their contents studied (for more detailed methods and lists of localities, see Bogusch et al 2015, Astapenková et al 2017. The nest structures, number of brood cells, materials used, pollen and prey contents, and shape of brood chambers were studied and measured, and all larvae were kept until the adults hatched.…”

“…Very specific guild of bees and wasps make their nests in old cigar galls of the frit flies genus Lipara Meigen, 1830, on common reed (Phragmites australis). Astapenková et al (2017) reviewed that 39 species use these specific cavities for their nesting, and around ten other species are commonly recorded ovipositing in their nests (parasitoids and nest cleptoparasites). Several species use exclusively or very preferably these galls for their nesting while Hylaeus pectoralis Foerster, 1871, is the typical example of specialist nesting exclusively in reed galls (see Bogusch et al 2017).…”

Nuevos datos sobre la distribución de <em>Lipara</em> Meigen, 1830 (Diptera: Chloropidae) y sus clorópidos inquilinos en la península ibérica

“…The galls of Lipara, especially those of L. lucens, also serve as microhabitats and important refuges for other chloropids and other insects such as Hymenoptera, Coleoptera or Lepidoptera (De Bruyn, 1985;Nartshuk & Andersson, 2013;Heneberg et al, 2014;Bogusch et al, 2015Bogusch et al, , 2016Astapenková et al, 2017).…”