New fossil records of Xyelidae (Hymenoptera) from the Middle Jurassic of Inner Mongolia, China

A new genus and two new species of Xyelidae Newman, 1834 (Hymenoptera Linnaeus, 1758), Platyxyela tenuis sp. nov. and Scleroxyela daohugouensis gen. et sp. nov. are described and illustrated from the Middle Jurassic Daohugou Beds of Ningcheng, Inner Mongolia, China. Platyxyela tenuis sp. nov. (Xyelinae Newman, 1834, Liadoxyelini Rasnitsyn, 1966) can be distinguished from its congeners by short forewing length and ovipositor sheath strongly narrowed toward acute apex. Scleroxyela daohugouensis gen. et sp. nov. is placed within Macroxyelinae Ashmead, 1898, Xyeleciini Benson, 1945 based on pterositigma completely sclerotised and costal space sclerotised before ptrostigma, 1-Rs half as long as 1-M, and 1m-cu short. It is the first recorded species of Xyeleciini in Daohugou Beds. Furthermore, an updated key of identification of subfamilies and tribes of Xyelidae is provided. Our findings of new morphological data provide insights into the early evolution of Hymenoptera, as well as effectively enrich our understanding of the diversity of Xyelidae in the Mesozoic.

Trachelus stipa (Hymenoptera: Cephidae), a new stem sawfly from Central Anatolia associated with feather grass (Stipa holosericea, Poaceae)

Trachelus stipa is described from Central Anatolia, Turkey. It is morphologically close to T. flavicornis and T. troglodyta regarding the structure of the preapical sterna of the male. It is unique among Trachelus species regarding the shape of the claw of the posterior leg, the size of the denticles of the ovipositor and the short valvula 3 of the ovipositor sheath in the female, and the distally notched hypopygium in the male. The genetic distance found in two mitochondrial (COI and cyt b) and one nuclear (EF-1α) gene regions support the recognition of this species and its placement within Trachelus, although the shape of the ovipositor sheath disagrees with this concept. Stipa holosericea, the host of T. stipa according to field observations, represents the first record of a feather grass as the host of a sawfly species.

Phylogeny and Revision of Toechorychus Townes (Hymenoptera, Ichneumonidae, Cryptinae), with descriptions of thirty-five new species

The Neotropical Toechorychus Townes is revised, cladistically defined, and diagnosed. A total of 40 species are recognized, 35 of which are described as new: T. amapaeus Tedesco, sp. nov., T. amazonensis Tedesco, sp. nov., T. barticus Tedesco, sp. nov., T. benius Tedesco, sp. nov., T. bombuscarus Tedesco, sp. nov., T. calius Tedesco, sp. nov., T. callangus Tedesco, sp. nov., T. catarinus Tedesco, sp. nov., T. coaracius Tedesco, sp. nov., T. darienus Tedesco, sp. nov., T. fluminensis Tedesco, sp. nov., T. guarapuavus Tedesco, sp. nov., T. heredius Tedesco, sp. nov., T. itapuensis Tedesco, sp. nov., T. jatainus Tedesco, sp. nov., T. kawus Tedesco, sp. nov., T. linaresius Tedesco, sp. nov., T. marcapatus Tedesco, sp. nov., T. marowijnus Tedesco, sp. nov., T. martinus Tedesco, sp. nov., T. melgassus Tedesco, sp. nov., T. morelus Tedesco, sp. nov., T. napus Tedesco, sp. nov., T. nourageus Tedesco, sp. nov., T. ondensis Tedesco, sp. nov., T. paramaribus Tedesco, sp. nov., T. pirrus Tedesco, sp. nov., T. sinopus Tedesco, sp. nov., T. surinamus Tedesco, sp. nov., T. taperinus Tedesco, sp. nov., T. teutonius Tedesco, sp. nov., T. tumazulus Tedesco, sp. nov., T. vilhenus Tedesco, sp. nov., T. vinhaticus Tedesco, sp. nov., T. zulius Tedesco, sp. nov. The other valid species are T. abactus (Cresson), T. albimaculatus (Taschenberg), T. brevicaudis (Szépligeti), T. cassunungae (Brauns), and T. stramineus (Taschenberg). Toechorychus can be recognized by the epicnemial carina usually not reaching more than 0.3 of the distance to subtegular ridge; dorsal valve of ovipositor with a subapical V-shaped sulcus; ovipositor with a subapical constriction; ovipositor sheath about 0.1 as long as hind tibia; and dorsal margin of pronotum swollen. A key and descriptions, including photographic illustrations and distribution maps, are provided to all valid species; a cladistic analysis of the genus is also performed. Seventy three new characters are proposed for the analysis of Cryptinae phylogeny. Toechorychus was recovered as a monophyletic group supported by 7–17 synapomorphies, closely related to Lymeon Förster and Acerastes Cushman. Two new synapomorphies are discovered for Toechorychus, a subapical V-shaped sulcus at the dorsal valve of the ovipositor, and a subapical constriction of the ovipositor present basad of the apical teeth of the ventral valve. Published host records were compiled and three new records are provided as follows: T. albimaculatus is a parasitoid of Mischocyttarus drewseni (Saussure) (Vespidae, Polistinae); T. stramineus is a parasitoid of M. basimacula (Cameron) and T. heredius sp. nov. is a parasitoid of M. collarellus Richards. A neotype is designated for T. cassunungae.

Platyxyela gen. nov. (Hymenoptera, Xyelidae, Macroxyelinae) from the Middle Jurassic of China

Platyxyela unica, gen. et sp. nov., assigned to the Macroxyelinae of Xyelidae is described from the Middle Jurassic Jiulongshan Formation of eastern Inner Mongolia, China. The new genus is characterized by Sc2 of the forewing meeting R at a short distance before the origin of Rs, the first section of Rs being shorter than the first section of M and nearly equal to Sc2, the antennomere 3 being shorter than the combined length of the remaining flagellomeres, the ovipositor sheath being much longer than wide. An updated key for the known genera of Macroxyelinae is given.

Bacterial Symbionts of the Brown Planthopper, Nilaparvata lugens (Homoptera: Delphacidae)

ABSTRACT The brown planthopper (Nilaparvata lugens Stål), the most destructive pest of rice, has been identified, including biotypes with high virulence towards previously resistant rice varieties. There have also been many reports of a yeast-like symbiont of N. lugens, but little is known about the bacterial microbes. In this study, we examined the bacterial microbes in N. lugens and identified a total of 18 operational taxonomic units (OTUs) representing four phyla (Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes) by sequencing and analyzing 16S rRNA gene libraries obtained from three populations of N. lugens, which were maintained on the rice varieties TN1, Mudgo, and ASD7. Several of the OTUs were similar to previously reported secondary symbionts of other insects, including an endosymbiont of the psyllid Glycapsis brimblecombei, an Asaia sp. found in the mosquito Anopheles stephensi, and Wolbachia, found in the mite Metaseiulus occidentalis. However, the species and numbers of the detected OTUs differed substantially among the N. lugens populations. Further, in situ hybridization analysis using digoxigenin-labeled probes indicated that OTU 1 was located in hypogastrium tissues near the ovipositor and ovary in biotype 1 insects, while OTU 2 was located in the front of the ovipositor sheath in biotype 2 insects. In addition, masses of bacterium-like organisms were observed in the tubes of salivary sheaths in rice plant tissues that the insects had fed upon. The results provide indications of the diversity of the bacterial microbes harbored by the brown planthopper and of possible associations between specific bacterial microbes and biotypes of N. lugens.

Phylogenetic relationships among Praini (Hymenoptera: Braconidae: Aphidiinae) aphid parasitoids, with redescription of two species

Phylogenetic relationships among four genera and 25 species of the tribe Praini (Braconidae: Aphidiinae) were investigated on the basis of 15 characters (13 morphological and two life history characters) using parsimony analysis. Areopraon Mackauer and Pseudopraon Starý are basal within the tribe. Both genera include species in which the external and internal types of pupation exist simultaneously [for example, Pseudopraon mindariphagum Starý, Areopraon lepelleyi (Waterston) and A. pilosum Mackauer)]. It can therefore be asserted that the external type of pupation behavior in the Praini probably originated in the polymorphic pupation behavior of ancient genera such as Pseudopraon and Areopraon. The genera Areopraon, Pseudopraon, and Dyscritulus Hincks form a monophylum separate from Praon. Areopraon is not retrieved as monophyletic. Species of the genus Praon Haliday possess conical apical spines on the top of the ovipositor sheath as an apomorphic character state. Within the genus Praon, we recognized the following closely related species groups: Parapraon + Praon dorsale-yomenae; and Praon rosaecola. Two Praini species are redescribed. Mesopraon Starý is a new synonym of Areopraon. Areopraon silvestre (Starý) and Areopraon helleni (Starý) are new combinations. A key to the recent Praini genera is given.

A new species of the genus Betuloxys Mackauer from European Russia (Hymenoptera: Aphidiidae)

Betuloxys kostyukovi sp. n. is described from the environs of St.Petersburg. The new species is closely related to B. assamensis Starý from India and differs in the areolation of propodeum and structure of antenna and ovipositor sheath.

A New Species of Microctonus (Hymenoptera: Braconidae)

This species keys to eleodis Vier. in Muesebeck's revision (U.S. Dept. Agric., Misc. Pub. No. 241, p. 16, 1936) and is very similar to that species and M. aethiops Nees. The female of M. eleodis differs in having a longer ovipositor sheath (about 1.2 times as long as abdomen bevond petiole), shorter petiole (only 1.9 to 2.2 times as long as its apical width), less strongly excavated and longer propodeum (only about 1.5 times as wide as long). The female of M. aethiops differs in having a pair of small dorsal pits near the middle of the petiole (both sexes), shorter ovipositor sheath (about 0.75 times as long as abdomen beyond petiole), slightly shorter petiole (about 2.2 times as long as apical width), and completely black petiole.