Hoverflies (Syrphidae: Diptera) in areas contaminated with heavy metals (Cd, Zn, Pb)

Habitats located in the area of the current and historical exploitation of zinc-lead (Zn-Pb) ores in the vicinity of Zakłady Górniczo-Hutnicze ‘Bolesław’ (southern Poland) were selected as the research area. This region is part of the so-called Olkusz OOR located within the macroregion of the Silesian Upland (Kondracki, 2011). It is characterised by the presence of high concentrations of trace elements in the soil, due to their presence in the bedrock, and contamination of the area with anthropogenic sources (mining and processing of Zn-Pb ores). Both natural and anthropogenic sources of metals make the Zn, Cd and Pb content in the soils of the region at the level of 150–10,500 mg · kg⁻¹, 0.8–100 mg · kg⁻¹ and 140–2,600 mg · kg⁻¹, respectively, which many times exceed the standards allowed for Polish soils (Stone et al., 2002). The average annual temperature in this area is 8 °C (Szczypek, 1997). Annual rainfall (for the Olkusz region) is around 700–800 mm, with a peak in the period from June to September (Dziechciarz, 2002).

The OOR area is characterised by a very poor hydrological network. The main drainage watercourses are Biała Przemsza and Sztoła (Godzik, 2015), and the mining activities cause additional limitation of surface waters. Metalliferous soils are accompanied by specific plant complexes, forming the so-called calamine grasslands (Kapusta et al., 2010). They include plant species adapted to growth and development in an environment enriched with heavy metals (including Cd, Zn and Pb), for example, Biscutella laevigata subsp. Woycickii, Armeria maritima subsp. halleri. The unique soil conditions were most likely the reason to the survival of the local population of B. laevigata even in the maximum extent of the last glaciation (Wierzbicka et al., 2020). To protect these unique habitats, the areas NATURA 2000 ‘Armeria’ PLH120091 and ‘Pleszczotka’ PLH120092 have been created here. Also, the NATURA 2000 ‘Błędowska Desert’ as well as other large areas of sand exploitation is strongly associated with mining activities in this area. The calamine grasslands of the Olkusz area are accompanied by plantings of Scots pine (Pinus sylvestris), Banks pine (Pinus banksiana), black pine (Pinus nigra), Eurasian larch (Larix spp.), warty birch (Betula pendula) and American bird cherry (Prunus serotina). Over half of the OOR area is covered by non-forest communities namely meadows, xerothermic grasslands, psammophilous grasslands, segetal and ruderal communities (Godzik, 2015). The areas elevated on limestone, which are often occupied by beech forests or rock-plant communities, are of a completely different character.

The research was conducted in the following localities: Bukowno, Hutki, Klucze, Pazurek, Rasztyn, Ryczów, Rodaki and Ujków Stary (US) (Figure 1).

Figure 1

Syrphidae were collected in the years 2015–2021. In the first year of research, quantitative samples of syrphids were collected. In the following years, the material was collected qualitatively. The insects were caught in the period from early spring to late summer using an entomological net in the morning hours. Most of the insects were caught during active flight, while feeding on nectar or pollen, or in food traps – a sugar solution spread over the leaf surface. Captured insects were killed, pinned and identified to species by using the entomological keys: Stubbs and Falk (2002), Bartsch (2009a, 2009b), Van Veen (2004), Speight (2020).

Other collections available to the authors were also analysed for specimens from the area under study (collections of the Museum and Institute of Zoology of the Polish Academy of Sciences in Warsaw and the collection of Bogusław Soszyński [BS]. Only two specimens of species were not confirmed in the current research and were from these two collections Melangyna ericarum (COLLIN, 1946) and Brachypalpus chrysites EGGER, 1859.

To determine the trophic structure of the caught adults and to facilitate its comparison with the results of research conducted by Klasa and Soszyński (2011) in the ONP, the following division was adopted, taking into account the diet of the larvae: predators and parasites, aquatic saprophages (SW), terrestrial saprophages, nest saprophages, phytophages, mycophages, coprophages. The significance difference among trophic groups was checked using G-test (Sokal and Rohlf, 1981).

Material: 01.05.2020, Bukowno (Diabla Góra), 1M (male), on hawthorn flowers.

Occupies habitats located in forests with pine or spruce. Larvae develop in hollows in pine trees (Vujić et al., 2020).

Material: ‘IX’ 1968 (Pustynia Błędowska), 1M, leg. R. Januszek, det. Bańkowska R. (coll, MiIZ PAN). Record is based on a museum collection. According to label data, the specimen was probably collected in the Błędów Desert in 1968. The label was handwritten and there is confusion if ‘IX’ refers to September which is very unlikely for B. chrysites or it is just miswriting of ‘IV’ April. It is a rare mountain and spring species associated with rich Beech-Abies forests. Larvae develop in wet humus on tree cavities (Speight, 2011). Suitable habitats still occur in the east part of Błędów Desert where old beech forest is still present. Numbers of field surveys in spring time during this study in order to rediscover this species in the area were unsuccessful.

Material: 19.05.2015, Ujków Stary (road by the park), 1M, leg. Mielczarek Ł.; 19.05.2015, Ujków Stary, 1M, leg. Mielczarek A.

This is a rare species that prefers deciduous forests with old trees. Larvae are still unknown, but most probably they develop in hollows of deciduous trees. Flight period is from late April to August (Speight, 2011). Threat category – NT on the Red List of Endangered Animals in Poland.

Material: 18.05.2015, Klucze (Czubatka), 3M, leg. A. Mielczarek.

Although this species prefers pine and spruce stands, which in Poland occupy huge areas, adults are rarely caught. It can be abundant locally under appropriate conditions. Imagines can be found on pine wood yards and on flowers of Ranunculus, Seseli and Potentilla erecta. Flight period is from May to August. Larvae are known to develop under pine bark in wet tree humus formed from the frass of Ips and Acanthocinus (Speight, 2011). It is a rarely caught species. Threat category is DD on the Red List of Endangered Animals in Poland.

Material: 19.05.2015, Ujków Stary, 1M, leg. Mielczarek Ł.; 01.05.2020, Pustynia Błędowska (Chechło), 4F (females), leg. Mielczarek Ł.; 06.06.2021, Ujków Stary (ecological site), 1F, leg. Mielczarek Ł.; 06.06.2021, Ujków Stary (ecological site), 9M, leg. Mielczarek Ł.; 10.06.2021, Ujków Stary (Armeria), 2M, leg. Mielczarek Ł.; 10.06.2021, Ujków Stary (Armeria), 1F, leg. Mielczarek Ł.; 23.05.2021, Ujków Stary (ecological site), 1M, leg. Mielczarek Ł.; 23.05.2021, Ujków Stary (ecological site), 4F, leg. Mielczarek Ł.

This species occupies thermophilic deciduous forests and dry grasslands; found in March–June and August–September. They are undescribed larvae, but most likely associated with Verbascum (Vujić et al., 2020).

Material: 02.07.2015, Ujków Stary, 1M, leg. Mielczarek Ł.; 16.08.2015, Ujków Stary, 3F, leg. Mielczarek Ł.; 28.05.2020, Olkusz (Krucza Góra), 1M, leg. Mielczarek Ł.

It occurs locally in moist deciduous forests and at edges of meadows, clearings and undeveloped pastures and other open areas. Phytophagous larvae; imagines feed on pollen, nectar, honeydew. Flight period is from May to June. Larvae not described, but most likely associated with the roots of Primula plants (Vujić et al., 2020).

Material: 05.08.2017, Ryczów (limestone inselbergs), 1F, leg. Mielczarek Ł.; 06.2020, Klucze (limestone inselbergs), 3M, leg. Mielczarek Ł.; 08.2020, Klucze (limestone inselbergs), 3F, leg. Mielczarek Ł.

A species found in calcareous grasslands, gardens with Sempervivum. Larvae undescribed. The peak of the outbreak is in May and August (Speight, 2011).

Data published in Żóralski and Mielczarek (2021).

The species occurs in mountainous areas in moist, shady deciduous forests with Allium ursinum L. and A. victorialis (Schmid and Grossmann, 1998). Larvae (one per leaf) mine the leaves of Allium (Renema, 1999).

Material: 31.05.2015, Klucze (Pustynia Błędowska), 1F, leg. Mielczarek A.

Found in moist deciduous forests with a host plant of the Petasites genus. Imagines found in May on the flowers of the Apiaceae and Asteraceae families (Vujić et al., 2020).

Material: 05.08.2017, Ryczów, 1M, leg. Mielczarek Ł.

It occurs in deciduous mesophilic forests and within mountain grasslands. Flight period runs from May to August. Imagines visit flowers from the Apiaceae, Asteraceae families. Biology of the larvae remains unknown (Vujić et al., 2020).

Material: 02.07.2015, Ujków Stary, 1F, leg. Mielczarek Ł.; 16.08.2015, Ujków Stary, 11F, 5M, leg. Mielczarek Ł.

It is found in deciduous and coniferous forests. Flight period is in August, when imagines can be found on flowers of Apiaceae, Asteraceae, Achillea, Euphorbia and Galium. Larvae develop on fungi of the family Boletaceae (Vujić et al., 2020).

Material: 30.03.2019, Kuźnica Błędowska, 1M, leg. Mielczarek Ł.

The larvae were described on the basis of the material collected on spruce, in resinous leakages caused by Dendroctonus micans (Bańkowska, 1961). Flight period is from March till beginning of May.

Material: 19.05.2015, Ujków Stary, 1M, leg. Mielczarek Ł.; 23.05.2021, Ujków Stary (ecological site), 1F, leg. Mielczarek Ł.; 23.05.2021, Bolesław (staw na “Pasterniku”), 1M, leg. Mielczarek Ł.; 23.05.2021, Bolesław (staw na “Pasterniku”), 1F, leg. Mielczarek Ł.; 23.05.2021, Ujków Stary (Armeria), 1F, leg. Mielczarek Ł.; 23.05.2021, Ujków Stary (Armeria), 1M, leg. Mielczarek Ł.

Adult forms can be found in grasslands or in open deciduous forests from April to June. Imagines visit flowers from Apiaceae, Euphorbia, Prunus and Ranunculus. Larvae are unknown (Vujić et al., 2020).

Material: 31.05.2015, Pustynia Błędowska, 1M, leg. Mielczarek A.; 26.07.2015, Klucze (Czubatka), 1M, leg. Mielczarek Ł.; 16.08.2015, Ujków Stary, 1M, leg. Mielczarek Ł.

It is a forest species. Flight is from May to October. Imagines visit plants from Apiaceae, Crataegus, Galium, Hedera, Hieracium, Ranunculus and Sorbus. Larvae develop in fungi of the Boletaceae family (Vujić et al., 2020).

Observation: 05.2015, Olkusz, 1F, obs. Mielczarek Ł. on Hylotelephium spectabile,

Data presented in Żóralski and Mielczarek (2021).

The species occurs in dry deciduous forests, cliffs, strongly sunlight. It is associated with the sites of Hylotelephium telephium and Hylotelephium maximum (Rotheray, 1988).

Material: 21.07.2018, Rabsztyn (castle hill), 2M, leg. Mielczarek Ł.; 23.07.2017, Ujków Stary, 1M, leg. Mielczarek Ł.

This species prefers deciduous forests. Imagines found from April to October when they visit flowers from Apiaceae, Asteraceae, Foeniculum vulgare, Taraxacum and Cirsium. Larvae are in the fruiting bodies of Tuber truffles (Speight, 2011).

Material: 16.08.2015, Ujków Stary, 1F, leg. Mielczarek Ł.; 06.06.2021, Ujków Stary (ecological site), 1M, leg. Mielczarek Ł.

It cccurrs in wetlands/forests and rivers and streams in deciduous woodland, including carr; also in unimproved, montane grassland. Aduls visit white umbellifers: Foeniculum, Senecio. Flight period is in May/August (with peak in July) and on into September in southern Europe (Speight, 2011).

Material: 23.06.2014, Ujków Stary, 1ex., leg. Mielczarek A.; 06.06.2021, Ujków Stary (ecological site), 1F, leg. Mielczarek Ł.; 06.06.2021, Bukowno (Diabla Góra), 1M, leg. Mielczarek Ł.

It Preferred deciduous forest. Found on meadows, roadsides, forest edges. Flower visited: Berberis vulgaris, Crataegus, Tilia cordata, Ranunculus etc. Found to be active in June and July. Larvae described from aphid galls on Malus (Speight, 2011).

Material: 02.05.2014, Ujków Stary, 1F, leg. Mielczarek A.

Species occur in the conifer and deciduous forest. They visit flowers of Salix repens, Prunus padus, Ranunculus ficaria. Adults can be found during the period from May to June. Larvae undescribed (Speight, 2011). Threat category – VU on the Red List of Endangered Animals in Poland.

Material: 19.05.2015, Ujków Stary, 1M, leg. Mielczarek Ł.; 10.06.2021, Ujków Stary (Armeria), 10M, 4F, leg. Mielczarek Ł.

It occupies open, thermophilic forests and dry, open, calcareous grasslands rich in vegetation. Flight period is from May to July and it is a rare species. Larvae, probably phytophagous, develop in bulbs or rhizomes of host plants. Imagines visit flowers (Vujić et al., 2020).

Material: 26.07.2015, Ujków Stary, 1M, leg. Mielczarek A.

Found in deciduous riverside forests with the participation of poplars, willows and birches. Flight period runs in April/May and July/August. Imagines visit flowers from the Asteraceae, Euphorbia, Nartecium, Salix, Sorbus and Stellaria. Aphidophagous larvae are found on aphids on Cirsium arvense (Vujić et al., 2020).

Material: 18.05.2015, Klucze (Czubatka), 2F, leg. Mielczarek A.

It is found in coniferous forests with Abies, Picea and Pinus. It visit flowers of various plant eg. Calluna vulgaris, Cirsium vulgare, Crataegus, Prunus spinosa, Stellaria sp. in the period from May to September (Speight, 2011). Although sparse, locally occurring populations tend to be numerous.

Material: 02.05.1994, Pustynia Błędowska, 1F, leg. Soszyński B. det. Soszyński B. det. Mielczarek Ł.

This is new for Poland, but known in Great Britain (Scottish highlands), Denmark, Netherlands, Germany, Czech Republic, France, Switzerland, and Italy (Speight, 2011). Despite probably being associated with Scots Pine forest, it is a rarely collected species. Stubbs and Falk (2002) stated that species occur in native woods of Scots Pine but also in a fen far away from stands with pines. In Sweden occur in alpine heaths close to Pinus mugo (Bartsch, 2009b). Features of our specimen fit well with existing identification keys to Melangyna species although in general appearance (e.g. broader abdomen) it resembles more M. lucifera and M. lasiophthalma than the summer M. umbellatarum. Stubbs and Falk (2002) stated that the posterior part of the fore and middle femora should have black hairs. In our specimen, the second femur has completely white hairs and the first one only a few. Melangyna are presumably univoltine in Europe and occurrence of M. ericarum in spring in Poland is quite confusing despite records from the Western Europe show summer months. In our opinion, it is worth to review scarce M. ericarum material to check if it is the only one probable bivoltine species or it is a complex of two or more species differing in flight period.

Material: 10.04.2021, Pazurek, 2M, leg. Mielczarek Ł.; 10.04.2021, Pazurek, 1F, leg. Mielczarek Ł.; 11.04.2021, Kuźnica Błędowska, 1F, leg. Mielczarek Ł.; 01.03.2020, Pazurek, 3M, leg. Mielczarek Ł.; 01.03.2020, Pazurek, 2F, leg. Mielczarek Ł.

It is a common species, inhabiting forest clearings, forest edges, parks and thickets. It occurs in March and April. Larvae are aphidophagous; adults feed on pollen and nectar. The species behaves like an invasive and recently recorded as new for Europe (Bygebjerg, 2011; Mielczarek, 2011) and rapidly extending its range in other countries (van de Meutter et al., 2015). Recorded from Belgium, Denmark, Netherlands, Slovakia; France (Langlois and Speight, 2020), Asiatic Russia (Sakhalin) and Japan.

Material: 01.05.2020, Bukowno (Diabla Góra), 1F, leg. Mielczarek Ł.

It occurs in wetlands, fens, marshes, poorly-drained pastures, along woodland streams or field drains, beside lakes, ponds and rivers. Adults visit white umbellifers, Caltha, Euphorbia, Iris pseudacorus, Menyanthes, Mimulus guttatus, Potentilla erecta, Pyrus communis Ranunculus, Sorbus aucuparia, Taraxacum and Viburnum opulus. Flight period: end April/July. Larvae aquatic, associated with various aquatic plants, including Glyceria and Typha (Speight, 2011). The species was recorded only at Białowieża Primeval forest in Poland by Soszyński (1999). This record was based on one specimen reported by Theo Zeegers and Sander Turrnhout (Dijkstra and Kalkman, 1996). Record of this Atlantic species from Białowieża PF is unlikely and needs further study. The specimen from Diabla Góra was collected on flowering Crataegus monogyna at the top of the hill. Areas with marshes – potential habitat of Melanogaster larvae are present very close to Diabla Góra, in old sand mine Szczakowa where other aquatic hoverflies were present in numbers.

Material: 01.05.2020, Bukowno (Diabla Góra), 1F, leg. Mielczarek Ł.

Environment: open ground/forest/freshwater; close to water-bodies in river-flood plain grassland and alluvial forest. Adults visit flowers of umbellifers, Caltha, Crataegus, Prunus spinosa, Ranunculus, Rhamnus cathartica and Taraxacum. Flight period: Mid May/Mid August, with peak in June. Larvae: undescribed (Speight, 2011).

Material: 25.05.2018, Klucze (Czubatka), 1M, leg. Mielczarek Ł.; 10.06.2021, Ujków Stary (Armeria), 6M, leg. Mielczarek Ł.; 10.06.2021, Ujków Stary (Armeria), 3F, leg. Mielczarek Ł.

It is a rare species. It develops in open ground; sparsely-vegetated, dry, rocky ground appropriate for ant nests; unimproved pasture and grassy clearings in forest. It occurs in May to July. Larvae develop in colonies of Formica ants, feeding on their eggs and larvae (Speight, 2011).

Material: 18.05.2015, Klucze (Czubatka), 2F, leg. Mielczarek A.

The species found in clearings in deciduous and mixed forests (Bartsch, 2009a). It is an undescribed larvae, collected by Ł. Mielczarek from spruce galls.

Material: 13.07.2014, Ujków Stary, 1F, leg. Mielczarek A.; 13.07.2014, Ujków Stary, 1M, leg. Mielczarek A.

The larvae of the species are predators found in the Dreyfusia piceae colonies on fir trees and on coccidia on the black poplar, Italian form. A typical habitat is forest paths and forest edges. It flies from May to October with peak occurrence in June and July (Stubbs and Falk 2002).

Material: 03.05.2021, Bukowno (sand mine), 2F, leg. Mielczarek Ł.; 01.05.2020, Bukowno (Sztoła), 4M, leg. Mielczarek Ł.

It is a Spring species, often found on the edge of forests with Salix or Alnus spp. (Bartsch, 2009a). It prefers mid-forest lakes, springs and periodically flooded area (Żóralski and Trzciński, 2015).

Material: 13.09.2015, Ujków Stary, 1F, leg. Mielczarek A.; 05.2019, Bukowno (Diabla Góra), 9F, leg. Mielczarek Ł.

They prefer coniferous forests, especially Pinus. Adults flight in open woodland, clearings etc. They visited flowers of Myosotis, Cerastium and Potentilla in June/September. Larvae are apparently phytophagous (Speight, 2011).

Material: 13.09.2015, Ujków Stary, 1F, leg. Mielczarek A.; 07.2018, Bukowno (Spacerowa), 1M, leg. Mielczarek Ł.; 10.06.2021, Bolesław (Armeria), 1M, leg. Mielczarek Ł.; 23.05.2021, Bolesław (Staw na “Pasterniku”), 1M, leg. Mielczarek Ł.

Species found in conifer forests, tracksides, clearings etc. They visited flowers: Calluna vulgaris, Cirsium palustre, Hieracium, Ranunculus and Sedum acre. Fly period is from June to September (Speight, 2011).

Material: 13.07.2014, Ujków Stary, 1M leg. Mielczarek A.; 13.07.2015, Ujków Stary, 1M, leg. Mielczarek A.; 26.07.2015, Ujków Stary, 1F, leg. Mielczarek A.; 02.07.2015, Ujków Stary, 2M, leg. Mielczarek Ł.; 02.07.2015, Ujków Stary, 1F, leg. Mielczarek Ł.; 16.08.2015, Ujków Stary, 1F, leg. Mielczarek Ł.; 26.07.2015, Ujków Stary, 2M, leg. Mielczarek Ł.; 26.07.2015, Ujków Stary, 1F, leg. Mielczarek Ł.

Rare thermophilic species, and can therefore be found on xerothermic grasslands (Stennis and Stennis, 1997).

Material: 19.05.2015, Ujków Stary, 1F, leg. Mielczarek A.

Occurs in deciduous forests; scrub-invaded clearings in woodland and forests, scrub-edged tracks in woodland. Adults visit flowers: Acer pseudoplatanus, Crataegus, Prunus mahaleb, P. spinosa, Pyrus communis, male flowers of Salix spp. (including S. repens), Sorbus aucuparia, Viburnum. Flight period: beginning April/end May. Larva is aphidophagous (Speight, 2011).

Material: 07.05.2019, Klucze (Czubatka), 1F, leg. Mielczarek Ł.; 01.05.2014, Klucze (Czubatka), 1M, leg. Mielczarek A. (data published in Żóralski, 2018).

Species is connected with coniferous forests of Pinus spp. Adults often drink at damp mud in hot weather. They visited flowers of Crataegus, Salix etc. in the period May to June (Speight, 2011).

Material: 16.08.2015, Ujków Stary, 2F, leg. Mielczarek Ł.; 02.05.2014, Ujków Stary, 1F, leg. Mielczarek A.

Species connected with deciduous forest and scrubs with rich grand flora. Flies visiting flowers in small glades: Centaurea, Cirsium, Geranium, Hypericum and Veronica. Flight period is from May to August (Speight, 2011).

Material: 14.06.2021, Bukowno, 1F, leg. Mielczarek Ł.

The species occurs in moist, deciduous forests with birch and coniferous trees. Adults visit pignut flowers and possibly other umbellifers. It occurs in June and July (Stubbs and Falk, 2002). Larva is undescribed (Bartsch, 2009a).

Material: 26.07.2015, Klucze, 1F, leg. Mielczarek Ł.; 23.07.2017, Ujków Stary, 1F, leg. Mielczarek Ł.

Species is similar to S. manicata. Imagines visit flowers such as Angelica sylvestris. It occurs in mixed and deciduous forests with old aspen in the period from July to August. The larvae develop in rotten hollows of deciduous trees (Bartsch, 2009a).