OF BEE SPECIES (HYMENOPTERA, OF LVIV CITY PART FAMILIES COLLETIDAE LEPELETIER, 1841; HALICTIDAE THOMSON, 1869; MEGACHILIDAE LATREILLE, AND MELITTIDAE MICHENER,

Background . The article presents the results of the research on bees (Hymenop -tera, Apoidea) that occur in the city of Lviv. Bees are one of the most important pollina tors of many species of angiosperm plants. Research on species diversity of bees is very important not only on the wild nature territories, but also on the urbanized areas. Cities have a significant impact on bee species diversity, their biology and conservation. A comprehensive all Apoidea territory city Lviv conducted for the first time in more than 80 years and we hope that the presented ma terials will lay the foundation for further more detailed studies in this area. Conclusions . All species from the six families are native for the territory of Europe. The majority of them are polylectic (≈ 61 %), while the number of oligolectic species (≈ 23 %), or species that do not need to collect pollen (≈ 16 %) is much smaller. The Shannon’s diversity index is approx. 3.718 and the Shannon evenness measure is 0.799 (the honeybee Apis mellifera was excluded in both calculations). Analysis of the impact of urbanization and various environmental factors on the species diversity of bees requires further detailed studies.


INTRODUCTION
Bees are one of the most important pollinators of many species of wild angiosperm plants, so they are an integral component of many ecosystems. However, apart from wild plants, bees are also effective pollinators of many crops, orchards and ornamental flower beds on the farmlands and cities.
Research on species diversity of bees is very important not only for the wild nature territories, but also for urbanized areas. Research of wild bees in urban context started recently [3]. Over the past two decades, numerous contributions on the implications of urbanization for biodiversity conservation have been published [5,12].
Cities have a significant impact on bee species diversity, their biology and conservation. For example, the effects of pesticides, emerging pathogens from managed bees, climate change and land-use change are negatively correlated with bee species richness [6,7,9,10,11]. Higher diversity of flowering plants due to domestic orchards and ornamental flowers attract many polylectic species, but the abundance of oligolectic species could decrease at the same time. Urbanization often degrades nesting habitats for ground-nesting bees, but various structures like buildings and fences, can lead to an increase in abundance of cavity-nesters in urban habitats [6]. Despite a large number of investigations, many urbanization factors that influence biodiversity and pollination remain unstudied [13]. We are only beginning to understand the possible effects of habitat fragmentation on bees [4].
Significant research on bees on the territory of Western Ukraine was conducted by Maximilian Nowicki, Antoni Wierzejski (19th century), Jan Noskiewicz (the beginning of 20th century) and by Hanna Osychnyuk (the second half of the 20th century) [27]. A comprehensive study of all Apoidea on the whole territory of the city of Lviv has been conducted for the first time in more than 80 years and we hope that the presented materials will lay the foundation for further more detailed studies in this area.

MATERIALS AND METHODS
A brief description of the territory of Lviv City is given in the first part of the study [27]. The objects of our research were bees (Hymenoptera, Apoidea) that occur on the territory of the city of Lviv. We collected the specimens during the warm period of 2017-2019. We used the Moericke (yellow) pan traps and the entomological nets. Moericke yellow trap is a type of attraction traps (insects are attracted by colour) [17]. We used pans of 18 cm in diameter and 7 cm in depth as the most affordable. Traps were filled with water and a few drops of detergent were added.
Also, we collected dead bees (mostly killed by traffic) along the roads. Besides, we analyzed the entomological collection of Zoological Museum of Ivan Franko National University of Lviv (ZMD), collected during 2001-2016 by students and faculty staff.
We used the Shannon's diversity index (H) to assess species diversity. We also calculated the Shannon evenness measure (J) (the ratio of the observed diversity to maximum possible diversity of a given number of taxa) to facilitate the interpretation of the result [14]: where S is the total number of species; N is the total number of secimens and n i is the number of specimens in species i. Statistical analysis of the data was performed by the PAST (PAleontological STatistics, Version 2.17c) program.
In our collection, the Colletidae family is presented only by 3 species from a single genus -Colletes Latreille, 1802 ( Table 1).

Comments: Species conservation (IUCN Red List Categories): LC -Least concern
Примітки: Охорона видів (категорії Червоного списку МСОП): LC -"Найменший ризик" Colletidae is the poorest family in the number of species in our collection. All three species are native for the territory of Europe, solitary and nesting in soil. These species are listed in the category "Least concern" of the IUCN Red List. One species is polylectic and two other species are oligolectic.
Among the collected Halictidae, 11 species are solitary, 10 are primitively eusocial and 1 species is a kleptoparasite. 17 species nest in soil, and for 4 species, the mode of nesting is unknown. Polylectic species predominate in our collection of Halictidae (18 species or ≈ 82 % of all collected Halictidae), the number of oligolectic species is significantly lower (3 species or ≈ 14 %) and one species (≈ 4 %) does not need to collect pollen, because of its kleptoparasitism.
Bees of the Megachilidae family occurring on the territory of the city of Lviv  All collected Megachilidae species are native for the territory of Europe, solitary cavity-nesters and listed in the category "Least concern" of the IUCN Red List. Seven species (≈ 64 % of all collected Megachilidae) are polylectic and four species (≈ 36 %) are oligolectic.
In our collection, the Melittidae family is presented by 5 species from 3 genera -Dasypoda Latreille, 1802, Macropis Panzer, 1809, Melitta Kirby, 1802 ( Table 4).  All collected Melittidae species are native for the territory of Europe, solitary and nesting in soil. Four of them are listed in the category "Least Concern" and one -in the category "Near Threatened" of the IUCN Red List. Melittidae species are pollen specialists and forage on the plants from one family, genus or even species.
The summarized data for all six families of bees show a predominance of polylectic species (≈ 61 %), while the number of oligolectic species (≈ 23 %), or species that do not need to collect pollen (≈ 16 %) is much smaller. The Shannon's diversity index is ≈ 3.718 and the Shannon evenness measure is ≈ 0.799 (the honeybee Apis mellifera was excluded in both calculations).

CONCLUSIONS
The current composition of the bees' fauna within the city of Lviv includes 106 species, which belong to 25 genera and 6 families (Apidae, Andrenidae, Colletidae, Halictidae, Megachilidae and Melittidae).
The family Apidae is presented by 33 species and is the richest by the number of species among all the six families. The family Andrenidae is presented by 32 species, Halictidae -22 species, Megachilidae -11 species and Melittidae -5 species. The fami ly Colletidae is presented by 3 species only and is the poorest family in the number of species in our collection.
All species discussed above are native for the territory of Europe. The majority of them are polylectic (≈ 61 %), while the number of oligolectic species (≈ 23 %), or species that do not need to collect pollen (≈ 16 %) is much smaller.
The Shannon's diversity index is ≈ 3.718 and the Shannon evenness measure is ≈ 0.799 (the honeybee Apis mellifera was excluded in both calculations). This index indicates a high species diversity that can be associated with the variety of habitats and food sources.
Analysis of the impact of urbanization and various environmental factors on the species diversity of bees requires further detailed studies. This research can lay the basement for further studies in this field.

ACKNOWLEDGMENTS
We express the deepest thanks to Mykola Skyrpan, Kateryna Nazaruk and Oleksiy Malovanyi for the help with the sampling of the materials.

Сonflict of Interest:
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Human Rights: This article does not contain any studies with human subjects performed by any of the authors.
Animal studies: All institutional, national and institutional guidelines for the care and use of laboratory animals were followed.