A host driven parasitoid syndrome: Convergent evolution of multiple traits associated with woodboring hosts in Ichneumonidae (Hymenoptera, Ichneumonoidea)

The evolution of convergent phenotypes is of major interest in biology because of their omnipresence and ability to inform the study of evolutionary novelty and constraint. Convergent phenotypes can be combinations of traits that evolve concertedly, called syndromes, and these can be shaped by a common environmental pressure. Parasitoid wasps which use a wide variety of arthropod hosts have also repeatedly and convergently switched host use across their evolutionary history. They thus represent a natural laboratory for the evolution of trait syndromes that are associated with parasitism of specific hosts and host substrates. In this study, we tested the evolution of co-evolving characters in the highly diverse family Ichneumonidae associated with ovipositing in a specific and well-defined substrate: wood. Using a newly constructed phylogeny and an existing morphological dataset, we identified six traits correlated with the wood-boring lifestyle that demonstrate convergent evolution. At least one trait, the presence of teeth on the ovipositor, typically preceded the evolution of other traits and possibly the switch to parasitism of wood-boring hosts. For each trait, we provide a historical review of their associations with wood-boring parasitoids, reevaluate the function of some characters, and suggest future coding improvements. Overall, we demonstrate the convergent evolution of multiple traits associated with parasitism of woodboring hosts and propose a syndrome in a hyper diverse lineage of parasitoid wasps.

Including fossils in phylogeny: a glimpse into the evolution of the superfamily Evanioidea (Hymenoptera: Apocrita) under tip-dating and the fossilized birth–death process

Using a fossilized birth–death model, a new phylogeny of the superfamily Evanioidea (including ensign wasps, nightshade wasps and hatchet wasps) is proposed, with estimates of divergence times for its constitutive families and for corroborating the monophyly of Evanioidea. Additionally, our Bayesian analyses demonstrate the monophyly of †Anomopterellidae, †Othniodellithidae, †Andreneliidae, Aulacidae, Gasteruptiida and Evaniidae, whereas †Praeaulacidae and †Baissidae appear to be paraphyletic. Vectevania vetula and Hyptiogastrites electrinus are transferred to Aulacidae. We estimate the divergence time of Evanioidea to be in the Late Triassic (~203 Mya). Additionally, three new othniodellithid wasps are described and figured from mid-Cretaceous Burmese amber as the new genus Keratodellitha, with three new species: Keratodellitha anubis sp. nov., Keratodellitha basilisci sp. nov. and Keratodellitha kirin sp. nov. We also document a temporal shift in relative species richness between Ichneumonoidea and Evanioidea.

Discovery of the male of a rare aulacid wasp, Pristaulacus emarginaticeps Turner, 1922 (Hymenoptera: Aulacidae) from Vietnam and Laos

Background

Pristaulacusemarginaticeps Turner, 1922 was described from a single female from Hòa Bình Province, Vietnam and it has remained the only recorded specimen.

New information

The male of Pristaulacusemarginaticeps Turner, 1922 is described for the first time and the species is newly recorded from Hà Tĩnh Province, Vietnam and Houaphanh Province, Laos.

A revision of the Chinese Aulacidae (Hymenoptera, Evanioidea)

The Chinese Aulacidae are revised, keyed and illustrated for the first time. In total twenty-five species are recorded from China, included within two genera Aulacus Jurine, 1807 and Pristaulacus Kieffer, 1900, with five and twenty species respectively. Among the treated species, six are newly described for science: Aulacus magnus sp. n., Pristaulacus calidus sp. n., Pristaulacus centralis sp. n., Pristaulacus fopingi sp. n., Pristaulacus obscurus sp. n., and Pristaulacus pseudoiosephi sp. n. Three species are newly recorded from China: Pristaulacus excisus Turner, 1922, Pristaulacus iosephi Turrisi & Madl, 2013, and Pristaulacus rufobalteatus Cameron, 1907.

Per arborem ad astra: morphological adaptations to exploiting the woody habitat in the early evolution of Hymenoptera

We survey morphological features of larval and adult wasps that undergo their entire larval development inside wood and interpret them in view of the lifestyle. The evolution of some of the characters is explored by mapping them on a recently published phylogeny of Hymenoptera. Based on this phylogeny, it is reasonable to assume that wood-living wasps evolved from a xylophagous/mycetophagous stage as displayed by woodwasps to a carnivorous/parasitoid lifestyle, preying on woodboring insect larvae. The latter mode of life is probably ancestral to the Apocrita which comprise the majority of the order; they share this lifestyle with their sister group, the Orussidae. However, most apocritan wasps have radiated into other habitats, the Orussidae and Stephanidae apparently being the only taxa that have retained the ancestral lifestyle of carnivorous wasps. Other apocritan lineages associated with wood (e.g., Aulacidae, Megalyridae, basal Cynipoidea and some Ichneumonoidea and Chalcidoidea) possibly entered this habitat secondarily and independently acquired morphological traits associated with it. The woody habitat was occupied by Hymenoptera during a crucial stage in their evolution where the transition from the phytophagous to carnivorous lifestyle took place. The anatomy of both larva and adults was extensively transformed in the process.