Claire Villemant

Ecological effects and management of invasive alien Vespidae

Insect species associated with human goods continue to be accidentally introduced into new locations. A small proportion of these introduced species become invasive, causing a range of impacts in the receiving community. It is therefore important to evaluate the patterns of which species become invasive and which strategies are most successful in managing them. This review assesses the distribution, abundance, impact and management of the invasive Vespidae worldwide. We identified 34 vespid species known to be introduced around the world, but the seven most invasive species are all eusocial. Most introduced Vespidae only occur in one or two countries, but some areas have become geographic hotspots of invasion: Hawaii (15 species), North America (eight species), New Zealand (five species), Australia (four species) and South America (four species). Two invasive species, Vespula vulgaris and V. germanica have become particularly widespread and abundant with a range of impacts on biodiversity and ecosystem function. Other successful invasive species include several Polistes spp., which affect local biodiversity through direct predation or competition for food or space. Toxic baiting has been the most successful control strategy against invasive vespids to date, although this has mostly been small scale experimental management as it has proved difficult to develop commercial control products. Development of shelf-stable lures or baits combined with suitable toxins or pathogens could overcome some of the commercial impediments. Several attempts at biological control using parasitoids have not successfully reduced invasive wasp populations, although the biocontrol agent has only established in one case. The social structure of colonies and their high reproductive efficiency have facilitated invasion by these species, but it also means management at the population level will be difficult. This emphasises the need to prevent such invasions from occurring in the first place.

Observations on the colony activity of the Asian hornet Vespa velutina Lepeletier 1836 (Hymenoptera: Vespidae: Vespinae) in France

Abstract Observations were made in the south-west region of France on the activity and behaviour of Vespa velutina workers from a nest reared in captivity as well as from free-living colonies. Seasonal nest development, daily extranidal activity, daily time budget allocated to nest construction and carbohydrates, water, pulp or prey collection were determined from the captive colony. In the meantime, nestmate and non-nestmate interactions were assessed. The percentages of pulp pellets and prey collections brought back by foragers were also determined from the free-living colonies and showed a noticeable preference of the hornet for honey bees. These preliminary data allow further investigations on the biology and behaviour of this Asian invasive species in the view to better assess its impact on biodiversity in France.

Can parasites halt the invader? Mermithid nematodes parasitizing the yellow-legged Asian hornet in France

Since its introduction in France 10 years ago, the yellow-legged Asian bee-hawking hornet Vespa velutina has rapidly spread to neighboring countries (Spain, Portugal, Belgium, Italy, and Germany), becoming a new threat to beekeeping activities. While introduced species often leave behind natural enemies from their original home, which benefits them in their new environment, they can also suffer local recruitment of natural enemies. Three mermithid parasitic subadults were obtained from V. velutina adults in 2012, from two French localities. However, these were the only parasitic nematodes reported up to now in Europe, in spite of the huge numbers of nests destroyed each year and the recent examination of 33,000 adult hornets. This suggests that the infection of V. velutina by these nematodes is exceptional. Morphological criteria assigned the specimens to the genus Pheromermis and molecular data (18S sequences) to the Mermithidae, due to the lack of Pheromermis spp. sequences in GenBank. The species is probably Pheromermis vesparum, a parasite of social wasps in Europe. This nematode is the second native enemy of Vespa velutina recorded in France, after a conopid fly whose larvae develop as internal parasitoids of adult wasps and bumblebees. In this paper, we provide arguments for the local origin of the nematode parasite and its limited impact on hornet colony survival. We also clarify why these parasites (mermithids and conopids) most likely could not hamper the hornet invasion nor be used in biological control programs against this invasive species.

Geographic Variation of Melanisation Patterns in a Hornet Species: Genetic Differences, Climatic Pressures or Aposematic Constraints?

Coloration of stinging insects is often based on contrasted patterns of light and black pigmentations as a warning signal to predators. However, in many social wasp species, geographic variation drastically modifies this signal through melanic polymorphism potentially driven by different selective pressures. To date, surprisingly little is known about the geographic variation of coloration of social wasps in relation to aposematism and melanism and to genetic and developmental constraints. The main objectives of this study are to improve the description of the colour variation within a social wasp species and to determine which factors are driving this variation. Therefore, we explored the evolutionary history of a polymorphic hornet, Vespa velutina Lepeletier, 1836, using mitochondrial and microsatellite markers, and we analysed its melanic variation using a colour space based on a description of body parts coloration. We found two main lineages within the species and confirmed the previous synonymy of V. auraria Smith, 1852, under V. velutina, differing only by the coloration. We also found that the melanic variation of most body parts was positively correlated, with some segments forming potential colour modules. Finally, we showed that the variation of coloration between populations was not related to their molecular, geographic or climatic differences. Our observations suggest that the coloration patterns of hornets and their geographic variations are determined by genes with an influence of developmental constraints. Our results also highlight that Vespa velutina populations have experienced several convergent evolutions of the coloration, more likely influenced by constraints on aposematism and Müllerian mimicry than by abiotic pressures on melanism.

Organization, usefulness and limitations of an ATBI (All Taxa Biodiversity Inventory): the inventory of terrestrial invertebrates in the Mercantour National Park

ABSTRACT We present here the objectives, organization and preliminary results of the invertebrate inventory of the Mercantour National Park (“Terrestrial Invertebrates Module” of the ATBI Mercantour/Alpi Marittime), carried out by 68 scientists and field-collectors from 2009 to 2012. The conceptual framework of an ATBI and the interactions between inventorying and frequently associated research aims are discussed. The sampling strategy adopted combined standardized multi-taxon sampling (continuous and occasional) with individual taxon-centred sampling. The successive tasks of field sampling, specimen coding, sorting and identification, molecular analysis and data management are briefly described. A coherent system of sample coding ensured the traceability of specimens. The project results in terms of sampling effort, abundance of collected invertebrate fauna and biological diversity are presented globally, by techniques, by sites and by higher taxonomic groups: 259,412 specimens were obtained from 761 sorted samples (out of 1243 samples collected), belonging to 1725 identified species and subspecies, in addition to which 37 species new to science have been recognized. These data are progressively being integrated into the CardObs database of the INPN and are partly accessible through the EDIT and GBIF websites. Molecular analyses (barcoding) have provided 2800 sequences (mostly for the COI gene in Gastropoda, Collembola and Hymenoptera). Analysis of these sequences indicates a significant amount of cryptic diversity in the material. From a macro-ecological perspective, endemicity in the park decreases globally from south to north and species richness decreases at higher elevations, but the data are uneven and patterns vary according to group. Based on this four-year experience, it appears that a smaller survey area with lower habitat diversity would be better suited to the aims of an ATBI when the available resources are limited, and would enhance the efficiency of collective work in the field.

Revision of the Eupelmidae Walker, 1833 described by Jean Risbec. Part 1: the slide mounted specimens housed at the Muséum national d’Histoire naturelle in Paris

ABSTRACT The present contribution is a catalogue of the Jean Risbec collection, including specimens mounted on microscope slides and belonging to Eupelmidae Walker, 1833 or originally described in Eupelmidae, as well as the point-mounted or card mounted specimens originally on these slides. Lectotypes are designated for 19 species. Eleven new combinations are proposed. The genus Fanamokala Risbec, 1960 described in Pteromalidae Dalman, 1820 is treated as a junior synonym of Eupelmus Dalman, 1820, subgenus Episolindelia Girault, 1914 n. syn. The following seven specific or subspecific synonymies are made: Anastatus aliberti var. bruniptera Risbec, 1951, Anastatus nezarae Risbec, 1951, and Anastatus rhynchitidi Risbec, 1951 n. syn. of Anastatus (Anastatus) aliberti Risbec, 1951, Brasema leersiae var. garouae Risbec, 1955 n. syn. of Eupelmus (Episolindelia) australiensis (Girault, 1913), Brasema leersiae Risbec, 1956 n. syn. of Eupelmus (Episolindelia) testaceiventris (Motschulsky, 1863), Bruchocida batataephila Risbec, 1951 n. syn. of Eupelmus (Eupelmus) elongatus Risbec, 1851, and Macreupelmus australis Risbec, 1952 n. syn. of Eupelmus (Eupelmus) fissicollis Risbec, 1952. Specific status is proposed for Anastatus pseudocreobotrae Risbec, 1951 n. stat., Eupelmus (Macroneura) psychephagus Risbec, 1951 n. stat., Neanastatus bicolor Risbec, 1951 and Neanastatus platygasteri Risbec, 1956 n. stat., all described originally as varieties. Vignalia halyomorphae Risbec, 1951 is removed from synonymy under Anastatus nezarae Risbec, 1951 as Anastatus (Anastatus) halyomorphae (Risbec, 1951) rev. stat. and n. comb.

Can species distribution models really predict the expansion of invasive species

Predictive studies are of paramount importance for biological invasions, one of the biggest threats for biodiversity. To help and better prioritize management strategies, species distribution models (SDMs) are often used to predict the potential invasive range of introduced species. Yet, SDMs have been regularly criticized, due to several strong limitations, such as violating the equilibrium assumption during the invasion process. Unfortunately, validation studies–with independent data–are too scarce to assess the predictive accuracy of SDMs in invasion biology. Yet, biological invasions allow to test SDMs usefulness, by retrospectively assessing whether they would have accurately predicted the latest ranges of invasion. Here, we assess the predictive accuracy of SDMs in predicting the expansion of invasive species. We used temporal occurrence data for the Asian hornet Vespa velutina nigrithorax, a species native to China that is invading Europe with a very fast rate. Specifically, we compared occurrence data from the last stage of invasion (independent validation points) to the climate suitability distribution predicted from models calibrated with data from the early stage of invasion. Despite the invasive species not being at equilibrium yet, the predicted climate suitability of validation points was high. SDMs can thus adequately predict the spread of V. v. nigrithorax, which appears to be—at least partially–climatically driven. In the case of V. v. nigrithorax, SDMs predictive accuracy was slightly but significantly better when models were calibrated with invasive data only, excluding native data. Although more validation studies for other invasion cases are needed to generalize our results, our findings are an important step towards validating the use of SDMs in invasion biology.

Reclassification of Some Bracon Species (Hymenoptera: Braconidae: Braconinae) Described by Ch. Granger and G. Szépligeti from Madagascar

Abstract. n Four braconid species from Madagascar described by Ch. Granger and G. Szépligeti in the genus Bracon are reclassified. A new genus, Grangerbracon gen. nov. (Braconidae: Braconinae) with the type species Bracon quinqueareolatus Granger, 1949, is described and illustrated. Bracon biareolatus Granger, 1949 and B. madagascariensis Szépligeti, 1913 are assigned to the genus Sculptolobus Yang, van Achterberg et Chen, 2008. Bracon griseopubescens Granger, 1949 is attributed to the subgenus Asiabracon Tobias, 1957. The lectotype for Bracon quinqueareolatus Granger is designated. All the listed species are redescribed, illustrated and their position is discussed.

A new genus of the tribe Pambolini (Hymenoptera: Braconidae: Exothecinae) from the Papua New Guinea with a key to the World genera

A new distinctive genus Spathiophaenodus gen. nov. from the tribe Pambolini (Braconidae: Exothecinae), with type species Spathiophaenodus annae sp. nov. from Papua New Guinea, is described and illustrated. The original key to the World genera of the tribe Pambolini is provided.

Charipinae Dalla Torre & Kieffer, 1910 (Hymenoptera: Cynipoidea: Figitidae) from the Mercantour National Park (Alpes-Maritimes, France), with descriptions of three new species

ABSTRACT Charipinae Dalla Torre & Kieffer, 1910 material collected during the ATBI of the Mercantour National Park in the Alpes-Maritimes (France) has been studied. Based on the study of 362 specimens, 35 species in four genera have been identified from: 23 Alloxysta Förster, 1869; 10 Phaenoglyphis Förster, 1869; one Apocharips Fergusson, 1986 and one Dilyta Förster, 1869. Of these, 19 species are recorded from France for the first time: Alloxysta abdera Fergusson, 1986; Alloxysta arcuata (Kieffer, 1902); Alloxysta brachycera Hellén, 1963; Alloxysta brevis (Thomson, 1962); Alloxysta fracticornis (Thomson, 1862); Alloxysta mullensis (Cameron, 1883); Alloxysta pilipennis (Hartig, 1840); Alloxysta postica (Hartig, 1841); Alloxysta proxima Belizin, 1962; Apocharips trapezoidea (Hartig, 1841); Phaenoglyphis abbreviata (Thomson, 1877); Phaenoglyphis americana Baker, 1896; Phaenoglyphis calverti Andrews, 1978; Phaenoglyphis evenhuisi Pujade-Villar & Paretas-Martínez, 2006; Phaenoglyphis fuscicornis (Thomson, 1877); Phaenoglyphis gutierrezi Andrews, 1978; and Phaenoglyphis longicornis (Hartig, 1840). All the Charipinae species identified are briefly described and compared with one another. Three new species are described and illustrated in detail: Alloxysta alpina Ferrer-Suay & Pujade-Villar, n. sp.; Alloxysta franca Ferrer-Suay & Pujade-Villar, n. sp. and Alloxysta pilae Ferrer-Suay, n. sp. A key to the species of Charipinae known from the Mercantour National Park is provided.