Lars Vilhelmsen

University of Copenhagen · Biosystematics

The fossil diversity of Diapriidae in Baltic amber, dated Upper Eocene, has been poorly investigated. However, some studies suggest that this family was already diversified at this time. This is supported by our present study of the Baltic amber collection of the Natural History Museum of Denmark, from which we describe and figure ten new species b...

Velvet ants (Mutillidae) are one of the largest families of solitary wasps in the Aculeata (Hymenoptera) and divided into eight subfamilies. Their larvae are ectoparasitoids of the larvae or pupae of other Aculeata, females use the sting for arresting the development of the host, as well as for defense. The sting apparatus of Mutillidae consists of...

Three species of Myrmeleontidae are currently known from Denmark: Myrmeleon bore, Myrmeleon formicarius and Euroleon nostras. Despite their unique and interesting life history, the faunistics of antlions in Denmark are in need of an update. Here, we primarily use the collections from the Natural Museum of Denmark and the Natural History Museum Aarh...

We present the first phylogenetic hypothesis for the cosmopolitan family Argidae based on both molecular and morphological data. Furthermore, we present a biogeographic scenario based on a dated phylogeny and interpret the evolutionary history of the family. Information from sequences of eight genes is analysed to reconstruct the phylogeny of the A...

Cimbicidae is a small family of Tenthredinoidea, containing the largest extant true sawflies. Body length variation across the family is mapped on an existing phylogeny, and some potential drivers of body size increase are explored: intrasexual competition between males, and mimicry patterns. Body length varies substantially within Cimbicidae, the...

Many early taxonomic works on North American bees were published by Europeans using specimens collected in the New World, some with type locations so imprecise that uncertainty on the nomenclatural status remains to this day. Two examples come from Fabricius (1745–1808) who described Andrena virescens Fabricius, 1775 and Apis viridula Fabricius, 17...

The larval stage remains unknown for many sawflies, making it difficult to explore the phylogenetic significance of larval morphology. Here, we assemble a data set from the larval anatomy of 22 genera of Argidae and Zenargidae. We scored 85 characters for 48 terminal taxa and use a maximum parsimony approach applying equal (EW) and implied weights...

The Argidae is the second most diverse family of the ‘Symphyta’ with more than 900 described species. Here we present the first comprehensive phylogenetic study for the family. We compare the adult skeleton anatomy of representatives of 57 described argid genera from different biogeographic regions. We score 223 characters for 117 terminal taxa, an...

The main synapomorphy for Aculeata is the sting apparatus, which allows the female to envenom potential prey or hosts. The sting is the modified ovipositor which is not used for laying eggs anymore. Here, we explore the morphology of the sting apparatus within the families of Chrysidoidea. 27 skeletal structures were recognized, including three (dp...

Fossils can be completely petrified, include original material or organic matter, contain unstable mineral parts or belong to the so-called subfossils consisting mostly of original material. The latter often do not differ significantly from zoological objects and can usually be stored in the same way (see section 2.7). Completely petrified fossils...

Adesha Cameron 1912, Indadesha Quicke 1986 and Aneuradesha Quicke 1986 are rarely found genera previously recorded only from India and Malaysia. In the present study these genera are reported for the first time from Pakistan, represented by four species: Indadesha achterbergi Quicke, Aneuradesha harleyi Quicke, Adesha albolineata Cameron and Adesha...

Two species of Orussidae are described: Ophrynopus rufocephalus new species and Ophrynopus savinai new species. The new taxa are analyzed with an existing data set for the Orussidae of the world. The results of the analyses indicate that the generic classification within the ophrynopine clade needs to be adjusted. Argentophrynopus Vilhelmsen & D.R....

Orussidae, a small family of parasitoid wasps targeting woodboring insect larvae, are characterized by having the ovipositor apparatus invaginated in the body and operated by a mechanism unique among Hymenoptera. The first and second valvulae when not in use lie in an invaginated ovipositor sack extending forward throughout the abdomen and thorax....

Abiinae is the second-largest subfamily in Cimbicidae, a small family of true sawflies (Tenthredinoidea). The subfamily is adequately defined, but the generic classification has been unstable. Currently, only two genera are regarded as valid: Abia Leach, 1817 and Allabia Semenov & Gussakovskij, 1937. We evaluate the generic classification of Abiina...

The parasitoid wasp family Ichneumonidae is arguably one of the groups for which current knowledge lags most strongly behind their enormous diversity. In a five-day meeting in Basel (Switzerland) in June 2019, 22 researchers from 14 countries met to discuss the most important issues in ichneumonid research, including increasing the speed of species...

The sting of the Aculeata or stinging wasps is a modified ovipositor; its function (killing or paralyzing prey, defense against predators) and the associated anatomical changes are apomorphic for Aculeata. The change in the purpose of the ovipositor/sting from being primarily an egg laying device to being primarily a weapon has resulted in modifica...

A survey of the ‘Symphyta’ of Colombia is conducted, based on information from literature as well as on examination of over 2,000 specimens from the major Colombian entomological collections. A total of 127 species are recorded from Colombia, representing six families: Argidae (48 species), Tenthredinidae (37) Pergidae (37), Xiphydriidae (3 species...

A survey of the ‘Symphyta’ of Colombia is conducted, based on information from literature as well as on examination of over 2,000 specimens from the major Colombian entomological collections. A total of 127 species are recorded from Colombia, representing six families: Argidae (48 species), Tenthredinidae (37) Pergidae (37), Xiphydriidae (3 species...

The South American genera of the Cimbicidae are reviewed. Five genera and nine species are recognized. Redescriptions of all genera and an identification key to all species are provided. All species are illustrated, including both sexes and aberrant specimens when relevant. The South American Cimbicidae are grouped in the subfamily Pachylostictinae...

The Cimbicidae is a small family including the largest extant true sawflies (Tenthredinoidea). It comprises four subfamilies, three of which have a northern hemisphere distribution (Abiinae, Cimbicinae – Holarctic/Oriental; Corynidinae – Palaearctic), whereas the Pachylostictinae are restricted to South America. No previous attempts have been made...

The African fauna of the rare family of parasitoid wasps, Orussidae, is reviewed. Five genera with 24 valid species are recognized. Chalinus davidi Vilhelmsen n. sp. is described; the male of Chalinus albitibialis Vilhelmsen, 2005, the male of Leptorussus madagascarensis Vilhelmsen, 2007 and the female of Orussus smithi Blank et al., 2006 are descr...

The Platygastroidea is a highly diverse group of small to minute parasitoid wasps. Despite the reduced size, the morphology of the maxillolabial complex of scelionids is very diverse and phylogenetically informative. 81 characters are scored for 129 genera (representing 75% of the total number of known extant genera of scelionids), as well as for s...

In the present study, a total of 153 species of Alysiinae (Hymenoptera: Braconidae) from Denmark are catalogued. Two species are described as new for science: Aspilota leptoarticulata Munk & Peris-Felipo sp. nov. and A. grandis Munk & Peris-Felipo sp. nov. Additionally, 38 alysiine species are recorded for the first time for the Danish fauna. A fau...

The Aculeata comprises some of the best known Hymenoptera. Traditionally, their sister group has been considered to be the Ichneumo-noidea; however, recent phylogenetic analyses contradict this hypothesis. We evaluate three potential candidates for the sister group of aculeate wasps: Ichneumonoidea, Evanioidea and Trigonaloidea. This is addressed b...

Ophrella seagi sp. n. is described and illustrated from a female and a male collected in French Guiana. Additional Orubidae from this country are listed in an Appendix. The new species differs from other members of Ophrella in a number of features, and the diagnosis of the genus is revised accordingly. A key to Ophrella species is included. The new...

Complex internal skeletal structures, despite their potential as rich sources of phylogenetic information, are still poorly described and used in comparative studies of insects in general, and bees in particular. In this study we present the results of a comprehensive investigation of the internal structures of the mesosoma of bees (e.g. prosternum...

Two new species of the rarely collected Australasian parasitoid wasp genus Orussobaius Benson, 1938 are described and considered in a phylogenetic context. Orussobaius nielspederi Blank & Vilhelmsen, n.sp. from Yamdena, Tanimbar Islands is characterized by extensive metallic sheen on the dorsal part of the abdomen in the females. Orussobaius bicolo...

Phylogenetic relationships of corbiculate bees have been a well-known focus of controversies over the past 30years. The majority of the morphological datasets support the monophyly of Apina+Meliponina, whereas molecular datasets recover Meliponina as sister to Bombina. This issue is especially critical to the proper understanding of the evolution o...

Directional evolution has played an important role in shaping the morphological, ecological and molecular diversity of life. However, standard substitution models assume stationarity of the evolutionary process over the time scale examined, thus hampering the study of directionality. Here we explore a simple, non-stationary model of evolution for d...

The Tenthredinoidea is the most diverse superfamily of non-apocritan Hymenoptera. It is also one of the largest herbivorous groups within the order, some species having substantial economic impact. Until very recently, no comprehensive phylogenetic analyses of the superfamily had been undertaken. This paper presents the largest morphological datase...

Orussus melanosoma Lee & Wei, sp. nov. from South Korea is described and illustrated. Phylogenetic analyses place the new species basally in Orussus, together with other species from the Far East. A key to species of Orussidae from the eastern Palaearctic is provided.

The Orussidae is a small and rare but phylogenetically important family of parasitoid wasps. The fossil record of the family is also very poor. Baltorussus velteni was described from Baltic amber from an allegedly female specimen. This and another recently discovered specimen are examined with microCT scanning and standard microscopy. We reveal tha...

The variation in ovipositor sculpture and additional features of the ovipositor apparatus in Tenthredinoidea is explored. Two outgroups and 85 species of tenthredinoids were examined, the emphasis of the taxon sampling being on Nematinae. Twenty-four morphological characters where scored and the data set was analysed under different weighting condi...

The genus Orussus is reviewed, with primary focus on taxa from the Oriental Region; a revised key to the world species is presented. The newly described species are analysed with a comprehensive morphological data set encompassing the entire family. The discovery of the new species corroborates the earlier proposed hypothesis that Orussus originate...

Previous molecular analyses of higher hymenopteran relationships have largely been based on subjectively aligned ribosomal sequences (18S and 28S). Here, we reanalyze the 18S and 28S data (unaligned about 4.4 kb) using an objective and a semi-objective alignment approach, based on MAFFT and BAli-Phy, respectively. Furthermore, we present the first...

Maximum likelihood tree recovered from the analysis of the combined molecular and morphological data (rRNA BAli-Phy aligned). Support values next to the nodes (or after species pairs) are bootstrap supports obtained from 1000 replicates based on both the BAli-Phy and the MAFFT alignments, respectively. Asterisks stand for maximal support. (TIF)

Commented table of primers used in this study. (PDF)

Maximum likelihood tree recovered from the analysis of the combined molecular data (rRNA MAFFT aligned). Support values next to the nodes (or after species pairs) are bootstrap supports obtained from 1000 replicates based on both the MAFFT and the BAli-Phy alignments, respectively. Asterisks stand for maximal support. (TIF)

The rare family Orussidae comprises the only parasitoid sawflies and are sister to the Apocrita comprising the vast majority of Hymenoptera. Because of this, their morphology and relationships have been particularly important for interpreting the morphology of and biological transitions within the order as a whole. Within the Orussidae the ophrynop...

Phylogenies are usually dated by calibrating interior nodes against the fossil record. This relies on indirect methods that, in the worst case, misrepresent the fossil information. Here, we contrast such node dating with an approach that includes fossils along with the extant taxa in a Bayesian total-evidence analysis. As a test case, we focus on t...

Hymenoptera exhibit an incredible diversity of phenotypes, the result of ~240 million years of evolution and the primary subject of more than 250 years of research. Here we describe the history, development, and utility of the Hymenoptera Anatomy Ontology (HAO) and its associated applications. These resources are designed to facilitate accessible a...

Sambia succinica gen. et sp.n. from Eocene Baltic amber is described and illustrated. It is apparently the first amber fossil that can be definitively assigned to Tenthredininae. It displays two diagnostic forewing characters for this subfamily: having a bend distally in vein R and the junctions of veins M and Rs + M with vein R being some distance...

The head capsule of a taxon sample of three outgroup and 86 ingroup taxa is examined for characters of possible phylogenetic significance within Hymenoptera. 21 morphological characters are illustrated and scored, and their character evolution explored by mapping them onto a phylogeny recently produced from a large morphological data set. Many of t...

We present the largest morphological character set ever compiled for Holometabola. This was made possible through an optimized acquisition of data. Based on our analyses and recently published hypotheses based on molecular data, we discuss higher-level phylogeny and evolutionary changes. We comment on the information content of different character...

We present the largest morphological character set ever compiled for Holometabola. This was made possible through an optimized acquisition of data. Based on our analyses and recently published hypotheses based on molecular data, we discuss higher-level phylogeny and evolutionary changes. We comment on the information content of different character...

The first comprehensive analysis of higher-level phylogeny of the order Hymenoptera is presented. The analysis includes representatives of all extant superfamilies, scored for 392 morphological characters, and sequence data for four loci (18S, 28S, COI and EF-1α). Including three outgroup taxa, 111 terminals were analyzed. Relationships within symp...