Research Article |
Corresponding author: Stefan Schmidt ( schmidt.s@snsb.de ) Academic editor: Thorleif Dörfel
© 2021 Christian Schmid-Egger, Stefan Schmidt.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Schmid-Egger C, Schmidt S (2021) Unexpected diversity in Central European Vespoidea (Hymenoptera, Mutillidae, Myrmosidae, Sapygidae, Scoliidae, Tiphiidae, Thynnidae, Vespidae), with description of two species of Smicromyrme Thomson, 1870. ZooKeys 1062: 49-72. https://doi.org/10.3897/zookeys.1062.70763
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The present study presents DNA barcoding results for 134 species of Central European Vespoidea, families Mutillidae, Myrmosidae, Sapygidae, Scoliidae, Tiphiidae, Thynnidae, and Vespidae, including DNA barcodes for 100 of the 114 German species. DNA barcoding resulted in unexpected diversity in several families, each with two or more genetic clusters identified by Barcode Index Numbers (BINs). Smicromyrme burgeri Schmid-Egger, sp. nov. and S. langobardensis Schmid-Egger, sp. nov. are described as new from Germany and Italy, respectively. A neotype is designated for Smicromyrme rufipes (Fabricius, 1878). The results of DNA barcoding are discussed in respect to detecting cryptic species and refining species limits.
Aculeata, DNA barcoding, Germany, German Barcode of Life (GBOL), new species, taxonomy
This study represents the first attempt to provide a comprehensive DNA barcode library for wasps of the superfamily Vespoidea for Central Europe, including the families Mutillidae, Myrmosidae, Sapygidae, Scoliidae, Tiphiidae, Thynnidae, and Vespidae. The library was compiled as part of several DNA barcoding projects at the Zoologische Staatssammlung München (
Total number of Vespoidea species included in the present dataset, number of species recorded in Germany, number of German species included in the present data, and German species for which no barcode sequence could be obtained.
Family | Total species | Species recorded in Germany | German species in this work | German species without DNA barcode |
---|---|---|---|---|
Mutillidae | 12 | 11 | 9 | Physetopoda ephippium*, Ronisia brutia |
Myrmosidae | 3 | 2 | 2 | |
Sapygidae | 4 | 4 | 4 | |
Scoliidae | 11 | 2 | 2 | |
Thynnidae | 4 | 2 | 2 | |
Tiphiidae | 4 | 4 | 4 | |
Vespidae | 96 | 89 | 80 | Allodynerus floricola, Ancistrocerus scoticus, Odynerus poecilus, O. simillimus, Parodontodynerus ephippium, Pseudepipona herrichii, Stenodynerus dentisquama, S. orenburgensis, Symmorphus fuscipes |
Totals | 134 | 114 | 103 |
The main source of material includes specimens from the collections of the Zoologische Staatssammlung München (
For the identification of Vespidae,
For DNA extraction, a single leg was removed from each specimen and sent to the Canadian Centre for DNA Barcoding (CCDB) in Guelph, Canada for DNA extraction and barcode sequencing. A complete list of voucher specimens included in the current release is given in Suppl. material
DNA extraction, PCR amplification, and sequencing were conducted at the Canadian Centre for DNA Barcoding (CCDB) using their standardised high-throughput protocols (
Sequence divergence statistics were calculated using the Kimura two parameter model of sequence evolution (
BINs provide an interim taxonomic system that allows defining species as Molecular Taxonomic Units (MOTUs) prior to detailed taxonomic studies including morphology. Sequences were aligned using the BOLD Aligner (amino acid-based hidden Markov models). The analyses are based on sequences with a minimum length of 500 bp and < 1% ambiguous bases. Genetic distances and summary statistics were calculated using analytical tools in BOLD and are given as mean and maximum pairwise distances for intraspecific variation, and as minimum pairwise distances for interspecific variations.
For the present study, DNA barcode sequences of 868 specimens of Vespoidea were analysed (Suppl. material
Dasylabris maura occurs with two subspecies in Central Europe, D. m. maura and D. m. clausa (Lepeletier, 1845). Dasylabris m. maura is restricted in its distribution to Germany and the eastern part of Central and Southern Europe (westwards to Italy). The south-western subspecies, D. maura clausa, occurs from south-western Switzerland to Portugal. Only three of 13 specimens analysed by DNA barcoding yielded sequences, with only one sequence longer than 500 bp, suggesting a primer mismatch issue. The three specimens that yielded usable sequences, two males from Brandenburg in eastern German and a female from the southern Alps in Italy, belong, based on their morphology, to D. m. maura.
In Germany, males of Physetopoda halensis occur with two colour variants, including a completely black form and a form with the mesosoma partly red. The colour forms exhibit minor morphological differences but were treated as conspecific (
Only four of 17 voucher specimens yielded DNA sequences, presumably, as in the previous species, caused by primer mismatch. The dataset includes sequences of four all-black males. No specimens with red mesosoma were available for analysis. The four specimens with sequence data include three specimens from south-western Germany and one from the Czech Republic. The latter specimen has been assigned a different BIN by the BOLD system. The BIN divergence and the maximum intraspecific diversity of 2.9% indicate that more than one species is subsumed under the name P. halensis in the black form, requiring further investigation into the taxonomy of this species, in particular in respect to the taxonomic status of the colour variants.
The sequences of Smicromyrme rufipes (Fabricius, 1878) from Germany and the southern Alps were assigned to three different BINs. Closer examination indicated the presence of different species that are also characterised by morphological differences. Males of Smicromyrme rufipes occur with two colour variants (
According to
Mutilla rufipes Fabricius, 1877: 313 “Habitat Halae Saxonum Dom. Hybner”.
lost (
(here designated) Germany • female; Brandenburg, Bad Freienwalde, Gabower Hänge; 52.826°N, 14.080°E; 15 Aug. 2001; Schmid-Egger leg.; coll.
Apart from the material shown in the list of specimens analysed by DNA barcoding (Suppl. material
To allow accurate identification of the taxon, a female specimen with full barcode sequence was selected as a neotype. The species was originally described from Halle in Sachsen-Anhalt, about 200 km south-west of the locality from where the neotype was collected. The species agrees with the descriptions of
The males of S. rufipes occur in two colour variants without transitional forms (
According to
Holotype
Germany • female; Bavaria, Nürnberg, E Zirndorf NSG Hainberg; 49.43°N, 10.99°E; 23 Jun. 2008; Schmid-Egger leg.; coll.
Specimens without barcode sequence, excluded from paratype series: Germany – Rhineland-Palatinate • 1 female; Hagenbach; 49.02°N, 8.20°E; 13 Jun. 2009; G. Reder leg., • 1 female; Wachenheim; 49.44°N, 8.17°E; 9 Aug. 1996, Schmid-Egger leg.; • 1 female; Ingelheim; 49.99°N, 8.06°E; Schmid-Egger leg.; – Baden-Württemberg • 1 female; Grißheim; 47.87°N, 7.57°E; 27 Jul. 1997; Schmid-Egger leg., • 1 female; Kronau; 49.22°N, 8.62°E; 17 Jul. 1989; Schmid-Egger leg.; • 1 female; Müllheim Schwärze; 47.81°N, 7.68°E; 26 Jul. 1992; France • 1 female; northern Vosges, Niederbronn-les-Bains; 48.95°N, 7.63°E; 2 Aug. 1991; Schmid-Egger leg. (all in coll CSE).
Smicromyrme burgeri sp. nov. resembles S. rufipes but the female has the frons with short dark setae, whereas S. rufipes has the frons with a distinct patch of long, golden setae. The golden setae may be shorter in small specimens of S. rufipes but they are always distinctly visible and allow a reliable identification. Females from traps with worn setation cannot be reliably identified. For the separation of S. burgeri sp. nov. from S. langobardensis sp. nov., see under this species.
Holotype female. Body length 5.5 mm. Colour. Black with the following parts red: clypeus, antennal base, antennomeres 1–4 (antennal apex black), mandible apart from black apex, mesosoma apart from black spot on pronotum medially, first tergite laterally, legs (tibia with some dark above). Morphology. Body with long erect setae, longest setae as long as fore tibia. Setae on dorsal side of body dark, lateral setae, and setae on underside of body white. Frons and mesosoma above with a few black adpressed setae. The following parts with spot or band of silver adpressed setae: tergite II mediobasally with a large, subcircular spot, laterally each with a longitudinal spot, apically with band. Tergite III completely covered with such pilosity. Propodeum with lamella, as large as width of middle flagellomeres. Pygidial area with longitudinal striae, reaching apex, apically somewhat divergent.
Female paratypes morphologically similar to the holotype, body length 4.0–5.5 mm.
Body length 7.0–9.0 mm. Colour. Black with the following parts red: collare, mesoscutum, scutellum, tegula. The male from France has the collare medially and the tegula black. Males agree in morphology with S. rufipes (see key and description in
Smicromyrme burgeri sp. nov. is known from the upper Rhine valley in Germany, an area from near the Swiss border in the south and the Frankfurt area in the north. Other records include sand dunes near Nuremberg in northern Bavaria. In addition, a male from the southern Alps in France was examined. The species has a typical southwest-submediterranean distribution with expansion to south-western Germany. The species is expected to occur elsewhere in southern France and northern Spain. Some records of S. rufipes mentioned by
The species is named after Frank Burger as a specialist for aculeate wasps and bees. He supported the research on Mutillidae by CSE during the initial phase of the project.
Holotype
Italy • male; Lombardia, Valtellina, 10 km E Sondro, Ponte in V.; 46.17°N, 9.96°E; 500 m a.s.l.; 9 Jul. 2006; Schmid-Egger leg.; coll.
Female specimens without barcode sequences, excluded as paratypes: 2 females, Italy, Valle d’Aosta, Pondel, 45.67°N, 7.22°E, 7.vii.1995, 25.vii.1999 and Valle d’Aosta, St. Pierre, 45.71°N, 7.23°E, 1.viii.1997, Schmid-Egger leg. (coll. CSE). The females differ from the paratype female in some characters and lack DNA barcode sequences and are therefore not considered in the description (frons and propodeum posteriorly more like S. rufipes).
Smicromyrme langobardensis sp. nov. agrees in most characters with S. rufipes and S. burgeri sp. nov. All examined males belong to the red form, as described under S. rufipes and S. burgeri sp. nov., with the exception that the metanotum is always red, whereas it is usually black in the other species. The male is characterised by shape and length of setae of the volsella (lateral view, Fig.
Holotype male. Body length 12.0 mm. Colour. Black with the following parts red: pronotum (pronotal base black), mesoscutum, scutellum, metanotum, tegula. Body with long white erect setae, setae of frons (apart vertex), scutellum and tergites VI and VII black. Morphology. Clypeus in basal half with keel, apically flat with two tubercles in lower third and two tubercles near apical margin. Mandible distinctly curved, with inner tooth near apex. Otherwise like S. rufipes. Genitalia see Fig.
Body length 8.0–12.0 mm. Colour of paratypes agrees with holotype except one male with darker red on mesosoma, and only pronotum laterally bright red as in remaining males.
Body length 5.0–5.5 mm. Agrees in all aspects with females of S. burgeri sp. nov. and S. rufipes apart from colour and extend of frontal setae. Frons bears 8–10 golden adpressed and isolated setae in S. langobardensis sp. nov., not forming a dense patch as in S. rufipes.
The species is only known from two localities in the Italian Alps, near the border to Switzerland. Records of S. rufipes from northern and central Italy and the Balkans (
The species is named after the type locality, the province Langobardia in northern Italy.
All species treated here key out as S. rufipes in the keys of
Males
1 | Basal setae of volsella in lateral view weakly curved backwards, not much longer than medial setae (Fig. |
Smicromyrme langobardensis sp. nov. |
– | Basal or some of the medial setae long and bent backwards over the remaining setae Figs |
Smicromyrme burgeri sp. nov. and S. rufipes |
Females
1 | Frons with a few black appressed setae only, without golden setae, Fig. |
Smicromyrme burgeri sp. nov. |
– | Frons with long golden appressed setae, Figs |
2 |
2 | Central Europe north of the Alps. Frons with large spot of golden setae, Fig. |
Smicromyrme rufipes |
– | Northern Italy. Frons with few (6–8) long golden adpressed setae, Fig. |
Smicromyrme langobardensis sp. nov. |
The family Myrmosidae was formerly treated as a subfamily of the Mutillidae. In Germany two species occur, Myrmosa atra and Paramyrmosa brunnipes (Lepeletier, 1845) (Fig.
Myrmosa atra is a widespread and common species in Germany. To our surprise, the barcoded specimens exhibited BIN divergence (see Supp. 2 and 3). Most specimens belong to one of two BINs, with specimens collected in Germany except the upper Rhine valley, and one additional specimen from Slovakia. Specimens of the second BIN were collected in the upper Rhine valley. The area is known for its fauna including south-western Mediterranean species that extend into the south-western parts of Germany. Other examples include Smicromyrme burgeri sp. nov. and the widespread species Smicromyrme rufipes. This distribution pattern and a maximum intraspecific distance of 8.8% in M. atra suggest the presence of more than one species. However, examination of male morphology did not yield any characters that would allow separation of the two BINs, and no females with barcodes were available from south-western Germany for morphological analysis.
Males from southwestern Germany are, on average, slightly smaller than specimens from other parts of Germany, and the propodeum has a shiny and smooth area laterally, whereas it is sculptured in specimens from other parts of Germany. However, this character varies in specimens that belong to populations of the widespread BIN, with small males also lacking the shiny area on the propodeum. We regard it as probable that M. atra consists of two species, but because of the apparent absence of morphological characters and with relatively few barcoded specimens at hand, we refrain from formally describing a new species.
DNA barcoding results of all four German species agree with species as traditionally defined using morphological characters.
The family Scoliidae is most diverse in the Mediterranean area and occurs with only two species in Germany. Preliminary barcoding results indicated a greater than expected genetic diversity which led us to analyse additional species from Southern Europe.
Campsomeriella thoracica is widely distributed in North Africa, southern Europe, and south-western Asia. The species occurs in two geographical male colour forms that are, although questionably (
Specimens from Morocco and Tunisia, agreeing in colour with the C. thoracica senilis, were assigned a different BIN than specimens from Egypt that represented C. t. thoracica, with a genetic distance of 2.2% between the two BINs. A third BIN was assigned to specimens from the United Arab Emirates. The red-coloured metasoma of males from the UAE suggested that they belong to C. t. thoracica but showed a genetic distance of 4.3% to its nearest neighbour in BOLD, an unidentified species of Campsomeriella, and probably represents a different species.
Megascolia maculata is widespread in the Mediterranean region and southern Central Europe. It is the largest scoliid wasp and, for that matter, the largest Hymenopteran species in the Western Palaearctic region. Traditionally three subspecies have been recognized (
DNA barcoding of specimens representing all three subspecies did not show any genetic sub-clustering, and in contrast, they mix completely. DNA barcoding therefore does not provide support for their subspecies status and considering the partly overlapping distribution, the current subspecies represents geographically based colour variation and should be regarded as such.
Micromeriella hyalina occurs from the Canary Islands and Morocco to Central Asia.
The family Tiphiidae occurs with four species in Germany, with one of them, T. femorata (F.), showing a high level of unexpected BIN divergence.
Tiphia femorata is a widespread and, like other species of the subfamily Tiphiinae, a parasitoid of soil-dwelling beetle larvae (Coleoptera: Scarabaeoidea,
In Germany, the Vespidae are represented by four subfamilies, including the Eumeninae, Masarinae, Vespinae, and Polistinae. A recent study of the latter subfamily revealed substantial BIN divergence in some species (
The subfamily Masarinae is represented by two Central European species, Celonites abbreviatus (Villers, 1798), and C. rugiceps Bischoff, 1928, the latter of which is regarded to be extremely rare or even extinct in Germany (
The results of DNA barcoding largely support the previously defined taxonomy of the family (
Both species are widespread in southern Europe, but rare in Germany. In the past they were regarded as conspecific or as subspecies, until
Eumenes coarctatus is a common species in Europe except from the northern parts. The species is traditionally regarded to consist of two subspecies, the mainly Central European E. c. coarctatus and E. coarctatus lunulatus Fabricius, 1804 from southern Europe, with differences in colour patterns between the two taxa (see Neumeyer, 2019, who treats E. coarctatus lunulatus as a synonym of E. coarctatus).
DNA barcoding revealed BIN divergence between specimens from Cyprus showing the colour pattern of E. coarctatus lunulatus, specimens from Germany with the colour pattern of the nominal subspecies, and specimens from northern Italy and France with a transitional colour pattern. The barcoding results suggest the presence of several species under E. coarctatus and, in addition, suggest that E. coarctatus lunulatus in fact represents a distinct species, demonstrating the need for further taxonomic study of this species complex.
Eumenes dubius has not been recorded from Central Europe, but it is widespread in southern Europe. The species exhibits an intraspecific distance of 5.7%, with specimens from Cyprus and Spain assigned to two different BINs, suggesting that at least two species are subsumed under E. dubius.
The species is common and widely distributed in Germany and was represented by three different BINs, each with a distinctive distribution pattern. All specimens from Germany were assigned to the same BIN, whereas two specimens from southern France and a specimen from north-eastern Italy belong to separate BINs, a pattern that was also observed in species of Smicromyrme. No morphological characters could be detected that would support the notion of more than one species under D. sylvestris.
Leptochilus alpestris includes two BINs with specimens from Italy and southern France. No German specimens of this rare species were available for DNA sequencing. The species is only known from a few local populations in xerothermic areas in south-western Germany (Baden-Württemberg).
The small and poorly known wasp family Thynnidae occurs with two species in Germany, including the widespread Methocha articulata (Latreille, 1792), a parasitoid of the larvae of Cicindela beetles, and Meria tripunctata (Rossi, 1790) that is regarded to be extinct in Germany (Schmid-Egger et al. 2012). Some southern European species of the genus Meria Illiger, 1807 showed BIN divergence and are in need of a taxonomic revision.
The present study presents DNA barcodes for 134 species of Vespoidea, including 103 (90%) of the 114 species that were recorded from Germany. The release represents, after the bees (
None of the barcoded vespoid species exhibited BIN sharing, and barcodes allow their unambiguous identification. BIN divergence was detected in 15 species (11%), suggesting either large intraspecific variation or presence of undetected species that were not recognised by taxonomists before. In species with BIN diversity, new taxa were formally described if genetic diversity was associated with diagnostic morphological differences. Undoubtedly, DNA barcoding expedited the discovery of the new taxa that would have been very unlikely by a traditional, morphology-based approach.
Several species of Vespoidea show a distribution pattern that appears to be a result of the separation of populations during periods of glaciation, when the species retracted from Central Europe to regions not covered by ice, and their re-invasion during warmer periods (
Vespoidea are generally known for their, compared to most other Hymenoptera, large body size and by their low species diversity, and have therefore for a long time attracted the attention of hymenopterists. Of the 114 species recorded from Germany, more than 90% were described during the 18th and 19th centuries. The taxonomy of most of them has not changed since then and most species are accepted as valid to the present day, except species of taxonomically difficult genera like Eumenes Latreille, 1802 (Vespidae, Eumeninae). The BIN divergence of species in several families of the Vespoidea came therefore as a surprise and even led to the discovery and description of new species. BIN divergence was even higher in some species of Polistes (Vespidae, Polistinae) that were treated in detail in an earlier study (
In absence of morphological differences between representatives of different BINs within a traditional species, we refrained from establishing new species, an approach that has also been followed during previous DNA barcoding studies, even when high levels of genetic diversity were detected within a traditional species (
Species with BIN divergence but without any morphological characters to support the species status of BIN representatives remain problematic. These include species like Myrmosa atra and Tiphia femorata, with two and five BINs, respectively, and maximum intraspecific distances of 8.9% in M. atra and 13.1% in T. femorata. If these genetic distances signify species diversity, then they are not correlated with equally pronounced morphological differences. Morphological examination did not reveal any consistent differences that would allow their separation, and we therefore left the species status of both species as is until further evidence will allow to decide this way or the other. This situation may seem unsatisfactorily at first sight, but it demonstrates a major difference between conventional and barcode-aided taxonomy. Traditionally, one was left with a species name, resulting either from the identification of a specimen using a key, or a name provided by a specialist, usually based on the most recent taxonomic revised of the taxon in question. However, a species name alone does not convey any information about intraspecific variation, nor distances to related species, information that would be critical for assessing the identity of a particular specimen. A name in combination with a DNA barcode, on the other hand, allows sequences and genetic distance information that accurately characterise a specimen to be carried over to subsequent taxonomic treatments aiding in resolving the taxonomic status, in particular if this information is publicly accessible. This would avoid losing information like distribution and life history traits, as it can happen when erroneously lumping species (
For species with an intraspecific variation larger than the commonly applied genetic distance threshold of 2%, and with multiple BINs, the information should be available “as is” in the globally accessible Barcode Life Database, including sequence data, photographs, collecting data and other supplementary information. Subsequent taxonomic assessment of these taxa based on morphology alone will most likely not aid much in refining species boundaries, and we therefore propose to use the current name in combination with an identifier like the Barcode Index Number (BIN) and a link to the auxiliary information in BOLD until sufficient data is available to clarify complexes of taxonomically problematic species.
The project was funded by the German Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung, Germany, project “German Barcode of Life”, FKZ 01LI1101B, 01LI1501B, 01LI1901B), and by the Bavarian Ministry of Education and Culture, Science and Art (Bayerisches Staatsministerium für Wissenschaft und Kunst, project “Barcoding Fauna Bavarica”). The sequence analyses for this study were supported, in part, by Genome Canada through the Ontario Genomics Institute, while informatics support was provided through a grant from the Ontario Ministry of Research and Innovation. The following specialists provided specimens and/or assisted with the identification of difficult taxa: Frank Burger, Hans-Joachim Jacobs, Tony v. Harten, Jakub Straka and Gerd Reder. The authors are indebted to Olga Schmidt for technical assistance and Jerome Morinière for GBOL project coordination.
List of voucher specimen
Data type: pdf file
Explanation note: List of voucher specimens with family, species, specimen ID, country of origin,collection date, depository, Barcode Index Number (BIN) and sequencing success (COI fragment length in bp, in square brackets number of unresolved bases).
DNA barcoding statistics
Data type: pdf file
Explanation note: Barcoding statistics of species with mean and maximum intraspecific distance, nearest neighbour species, minimum distance to nearest neighbour species, Barcode Index Number (BIN), country of origin and number of specimen. Distances are based on the Kimura 2-P model.
Neighbor-joining tree resulting from the analysis of DNA barcode sequences
Data type: pdf file
Explanation note: Neighbour-joining tree resulting from the analysis of DNA barcode (COI) sequences. Terminal taxa information include Sample ID, species, sex, country, province and (if available) Barcode Index Number (BIN).