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Silva Balcanica, 16(1)/2015

NEW RECORDS OF DOLICHOPODIDAE (DIPTERA) FOR BULGARIA. COMPARISON OF DOLICHOPODID DIVERSITY ON RIVER BANKS

AND IN SOME FORESTS OF THE UPPER THRACIAN PLAIN

Mihail Kechev 1, 2, Mariyana Ivanova11 University of Agribusiness and Rural Development – Plovdiv

2 Bulgarian Scientific Selection-Technical Union – Plovdiv

Abstract

The paper gives information about 35 dolichopodid flies collected in a small woodland and aquatic site situated in the Upper Thracian Plain (Bulgaria). Ac-cording to the abundance in the investigated ecosystem samples are divided in five groups: eudominant – Poecilobothrus regalis (54.17%), dominant – Hercostomus thraciensis (13.38%), subdominant – Hercostomus plagiatus (8.52%), rare – 8 spe-cies (1 – 5%), subrare – 24 species (

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pilot examination showing the need of investigations on ecosystem level searching for the reasons of diversities and similarities and explaining geographical and sea-sonal distribution of dolichopodid on a scientific basis.

STUDIED AREA

The investigated site (Fig. 1, 2 and 3), called Basha, is situated in the Upper Thracian Plain, 3 km southwest of the town of Chirpan (Bulgaria). Geographical coordinates – 42°10’39”N, 25°17’58”E, 149 m a. s. l. The sampling site represents a small pond (fig. 3), overgrown by different hygrophilous plants. The size of the pond is about 30 m length and 20 m width, depth – 1-1.5 m. The entire site is surrounded by agricultural lands, only a small stream flows on the south of it.

The trees are presented by Populus sp., Salix fragillis L., Salix triandra L., Juglans regia L., Sambucus nigra L., Morus alba L., Ailanthus altissima (Mill.) Swingle. The most dominant shrubs and grasses are presented by Urtica dioica L., Mentha aquatica L., Arctium lappa L., Aristolochia clematitis L., Conium macula-tum L., Cirsium vulgare (Savi) Ten., Rosa canina L., Rubus ceasius L., Cardamine sp. The plant species in the water are Typha latifolia L., Carex sp., Berula erecta (Huds.) Coville.

Most common vertebrate species in this place are marsh frog – Rana ridibun-da (Pallas, 1771) and European pond turtle – Emys orbicularis (Linnaeus, 1758).

MATERIAL AND METHODS

The material for the present work was collected by sweeping in the period from May 2013 to April 2014 (24 collecting trips from 2 May 2013 to 21 April 2014). The studied site was visited three times per month and insects were collected for 1 h per trip (from 5 to 6 p.m.). Adults collected in the field were put in vials con-

Fig. 1-3. Studied area: 1. Map of Bulgaria with an indication of investigated area; 2. Google Earth map of the site; 3. Picture of the studied site.

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taining 75% ethanol. The specimens were sorted in the laboratory with a binocular microscope. The faunistic list gives the following information: date of collecting, number of collected specimens per date (males and females), name of collector and distribution. One species is given with its generic name (Medetera sp.), because only female was collected. However, without male in one sample, the determination is difficult. Studies of Negrobov (1991), Pollet (2004) and Grichanov (2007) are used for species’ distribution. Google Earth software (version 7.1.1.1888) was used for Fig. 2, geographical coordinates and altitude.

The dominance structure is evaluated according to Heydemann’s classifica-tion of five degrees of dominance: eudominant species (>30% of all collected speci-mens), dominant (10-0%), subdominant (5-10%), rare (1-5%), subrare (

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where again pi is the proportion of individuals found in species i.For a finite community, this is

Interpretation: D is a measure of dominance, so as D increases, diversity (in the sense of evenness) decreases. Thus, Simpson’s index is usually reported as its complement 1-D (or sometimes 1/D or –lnD). Since D takes on values between zero and one and approaches one in the limit of a monoculture, (1-D) provides an intuitive proportional measure of diversity that is much less sensitive to species richness.

Simpson’s index: D The probability that two randomly selected individuals in the community be-

long to the same category (e.g., species). Simpson’s index of diversity: 1 – DThe probability that two randomly selected individuals in a community be-

long to different categories (e.g., species). Simpson’s reciprocal index: 1/DThe number of equally common categories (e.g. species) that will produce the

observed Simpson’s index. D is influenced by two parameters – the equitability of percent of each species

present and richness. For a given species richness, D will decrease as the percent of the species becomes more equitable.

The indices described above are calculated for two more sites described in previous studies (Kechev, 2012b; Kechev et al., 2014) and Sørensen index, also known as Sørensen similarity coefficient, is calculated:

a – common species in region A and B, b – number of species in region A that do not exist in region B, c – number of species in region B that do not exist in region A.

RESULTS

Faunistic listDIAPHORINAE Schiner, 1864Argyra argyria (Meigen, 1824)Material examined: 02.V.2013, 3♂♂; 10.V.2013, 1♂; 20.V.2013, 3♂♂;

03.VI.2013, 1♂; 10.VI.2013, 4♂♂; 10.VIII.2013, 1♂; 14.IV.2014, 2♂♂; 21.IV.2014, 1♂, leg. M. Kechev.

Distribution: Europe; North Africa: Morocco.

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Argyra leucocephala (Meigen, 1824)Material examined: 01.VII.2013, 1♂; 10.VII.2013, 2♂♂; 20.VII.2013, 1♂♂;

01.VIII.2013, 1♂; 10.VIII.2013, 1♂; 20.VIII.2013, 6♂♂, 2♀♀; 01.IX.2013, 2♂♂; 10.IX.2013, 2♂♂; 20.IX.2013, 1♀, leg. M. Kechev.

Distribution: Europe; North Africa: Algeria, Tunisia. Chrysotus femoratus Zetterstedt, 1843. New to Bulgaria.Material examined: 10.V.2013, 2♂♂; 03.VI.2013, 1♂, 2♀♀; 10.VI.2013,

2♀♀; 20.VI.2013, 1♂, leg. M. Kechev. Distribution: Europa; Transpalaearctic species. DOLICHOPODINAE Latreille, 1809Dolichopus griseipennis Stannius, 1831Material examined: 07.X.2013, 1♂, leg. M. Kechev. Distribution: Europe; North Africa: Algeria; Middle Asia. Dolichopus nitidus Fallèn, 1823Material examined: 20.VIII.2013, 1♀, leg. M. Kechev. Distribution: Europe; Transpalaearctic species; Oriental China.Dolichopus nubilus Meigen, 1824Material examined: 10.V.2013, 1♂♂; 10.VII.2013, 2♂♂; 20.VII.2013, 1♀;

20.VIII.2013, 1♀, leg. M. Kechev.Distribution: Europe; Asia: China, Kazakhstan, Tajikistan, Uzbekistan.Dolichopus salictorum Loew, 1871Material examined: 20.V.2013, 3♂♂, 3♀♀; 03.VI.2013, 1♂; 10.VI.2013,

5♂♂, 4♀♀; 20.VI.2013, 1♂, 1♀; 01.VII.2013, 1♂, leg. M. Kechev.Distribution: Bulgaria, Czech Republic, Hungary, Italy, Poland, Slovakia. Gymnopternus metallicus (Stannius, 1831)Material examined: 10.VI.2013, 1♂; 20.VI.2013, 2♂♂, 10.VII.2013, 1♂,

01.VIII.2013, 1♂, 1♀; 10.VIII.2013, 1♂, 1♀, 20.VIII.2013, 2♂♂, leg. M. Kechev. Distribution: Europe; Asia: Iran, Kazakhstan, East Russia: Altai.Hercostomus convergens Loew, 1857Material examined: 01.VII.2013, 1♂; 20.VII.2013, 1♀, leg. M. Kechev. Distribution: Europe.Hercostomus nanus (Macquart, 1827)Material examined: 02.V.2013, 2♂♂; 10.V.2013, 9♂♂, 5♀♀; 20.V.2013,

2♂♂, 5♀♀, leg. M. Kechev. Distribution: Europe.Hercostomus plagiatus (Loew, 1857). New for Bulgaria.Material examined: 10.V.2013, 1♂; 20.V.2013, 9♂♂, 25♀♀; 03.VI.2013,

7♂♂, 19♀♀; 10.VI.2013, 5♂♂, 2♀♀; 20.VII.2013, 1♂; 01.VIII.2013, 1♂; 10.VIII.2013, 4♂♂; 20.VIII.2013, 8♂♂, 6♀♀; 01.IX.2013, 1♂; 10.IX.2013, 1♂, 1♀; 20.IX.2013, 1♂; 07.X.2013, 1♀, leg. M. Kechev.

Distribution: Europe; North Africa: Algeria, Tunisia. Hercostomus thraciensis Kechev & Negrobov, 2015

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Material examined: 02.V.2013, 51♂♂, 12♀♀; 10.V.2013, 15♂♂, 12♀♀; 20.V.2013, 1♂; 01.IV.2014, 3♂♂; 14.IV.2014, 10♂♂, 14♀♀; 21.IV.2014, 15♂♂, 13♀♀, leg. M. Kechev.

Distribution: Bulgaria.Poecilobothrus regalis (Meigen, 1824)Material examined: 20.V.2013, 16♂♂, 3♀♀; 03.VI.2013, 123♂♂, 47♀♀;

10.VI.2013, 83♂♂, 35♀♀, 20.VI.2013, 52♂♂, 48♀♀; 01.VII.2013, 42♂♂, 31♀♀; 10.VII.2013, 32♂♂, 17♀♀; 20.VII.2013, 26♂♂, 9♀♀; 01.VIII.2013, 11♂♂, 4♀♀; 10.VIII.2013, 7♂♂; 20.VIII.2013, 4♂♂, 1♀, leg. M. Kechev.

Distribution: Europe. Sybistroma impar (Rondani, 1843)Material examined: 20.VI.2013, 1♂; 01.VII.2013, 1♂, 1♀; 10.VII.2013,

2♂♂, 5♀♀; 20.VII.2013, 1♂, 4♀♀; 01.VIII.2013, 1♂, 2♀♀; 10.VIII.2013, 1♀, leg. M. Kechev.

Distribution: Bulgaria, Greece, Hungary, Israel, Italy, Romania, Russia (Krasnodar), Turkey.

Sybistroma nodicornis Meigen, 1824Material examined: 02.V.2013, 2♂♂, leg. M. Kechev. Distribution: Europe; North Africa: Egypt; Asia: Iraq, Israel. MEDETERINAE Lioy, 1864Chrysotimus molliculus (Fallén, 1823)Material examined: 01.VIII.2013, 1♂, leg. M. Kechev.Distribution: Europe.Medetera sp.Material examined: 20.VI.2013, 1♀, leg. M. Kechev. RHAPHIINAE Bigot, 1852Rhaphium auctum Loew, 1857Material examined: 10.VII.2013, 2♂♂, 1♀, leg. M. Kechev.Distribution: Europe; Asia: Afghanistan. Rhaphium caliginosum (Zetterstedt, 1843)Material examined: 02.V.2013, 1♀; 10.V.2013, 1♂, 1♀; 20.V.2013, 1♀;

03.VI.2013, 1♂; 10.VI.2013, 1♀; 20.VI.2013, 3♂♂, 1♀; 01.VII.2013, 1♂, 1♀; 10.VII.2013, 3♂♂, 1♀; 20.VII.2013, 1♂; 01.VIII.2013, 2♂♂, 1♀; 10.VIII.2013, 1♀; 20.VIII.2013, 2♂♂, 1♀; 10.IX.2013, 1♂; 20.IX.2013, 1♂; 14.IV.2014, 1♂, 1♀; 21.IV.2014, 1♂, 1♀, leg. M. Kechev.

Distribution: Europe; North Africa: Algeria. Rhaphium monotrichum Loew, 1850Material examined: 10.VII.2013, 3♂♂, 2♀♀, leg. M. Kechev. Distribution: Europe; East Palaearctic: Baikal. Rhaphium pectinatum (Loew, 1859). New to Bulgaria.Material examined: 03.VI.2013, 1♂; 01.VII.2013, 1♂; 10.VII.2013, 2♂;

01.IX.2013, 1♂; 21.X.2013, 1♂; 19.III.2014, 1♀; 01.IV.2014, 1♂, leg. M. Kechev.

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Distribution: Europe. HYDROPHORINAE Lioy, 1864Scellus notatus (Fabricius, 1781)Material examined: 20.V.2013, 1♂, leg. M. Kechev. Distribution: Europe.SCIAPODINAE Becker, 1917Sciapus frater (Parent, 1927)Material examined: 01.VIII.2013, 4♀♀; 10.VIII.2013, 1♀, leg. M. Kechev. Distribution: Austria, Bulgaria, France, Slovakia, Russia (South). SYMPYCNINAE Aldrich, 1905Campsicnemus curvipes (Fallén, 1823)Material examined: 10.VIII.2013, 1♂, leg. M. Kechev.Distribution: Europe; Canary Islands; North Africa: Algeria. Campsicnemus simplicissimus Strobl, 1906Material examined: 02.V.2013, 1♂; 10.V.2013, 2♂♂, 5♀♀; 10.VI.2013, 1♂,

leg. M. Kechev. Distribution: Europe; Asia: Tajikistan. Lamprochromus bifasciatus (Macquart, 1827). New to Bulgaria.= Lamprochromus elegans (Meigen, 1830)Material examined: 01.VIII.2013, 1♂ male, leg. M. Kechev. Distribution: Europe.Micromorphus albiceps (Zetterstedt, 1843)Material examined: 20.V.2013, 3♂♂, 1♀, leg. M. Kechev. Distribution: Europe; Asia: Mongolia; North Africa: Algeria, Morocco. Sympycnus pulicarius (Fallén, 1823)Material examined: 20.V.2013, 3♂♂; 10.VI.2013, 1♂, leg. M. Kechev. Distribution: Europe; Nearctic: California. Syntormon denticulatus (Zetterstedt, 1843)Material examined: 07.X.2013, 1♂; 13.II.2014, 1♂, leg. M. Kechev. Distribution: Europe; Asia: Afghanistan. Note: The specimen of S. denticulatus collected on 13.II.2014 was found

around the brook, running on the south side of the studied ecosystem. Syntormon fuscipes (von Roser, 1840)Material examined: 14.IV.2014, 1♂, leg. M. Kechev. Distribution: Europe; Africa: Burundi, Kenya. Syntormon mikii Strobl, 1899Material examined: 20.V.2013, 1♂, leg. M. Kechev. Distribution: Europe; North Africa: Morocco, Tunisia. Syntormon pallipes (Fabricius, 1794)Material examined: 03.VI.2013, 3♂♂, 2♀♀; 10.VI.2013, 10♂♂, 5♀♀;

20.VI.2013, 8♂♂, 5♀♀; 01.VII.2013, 2♂♂; 20.IX.2013, 1♂, 2♀♀; 07.X.2013, 3♂♂, 4♀♀, leg. M. Kechev.

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Distribution: Europe; Asia: Afghanistan; Oriental China; North Africa: Alge-ria; Afrotropics: Madagascar, Tanzania.

Teuchophorus cristulatus Meuffels & Grootaert, 1990Material examined: 10.VIII.2013, 1♂; 20.VIII.2013, 1♂, leg. M. Kechev. Distribution: Bulgaria, Italy (Sicily), Turkey.Teuchophorus momacanthus Loew, 1859Material examined: 20.VII.2013, 1♂, leg. M. Kechev. Distribution: Europe.Teuchophorus spinigerellus (Zetterstedt, 1843)Material examined: 01.VIII.2013, 5♂♂, 1♀; 20.VIII.2013, 1♂, 3♀♀;

07.X.2013, 1♀, leg. M. Kechev.Distribution: Europe; Asia: Kazakhstan.

DISCUSSION

The total number of the collected dolichopodid flies in the investigated period was 1091. There were no flies during the last visit for 2013 (31st October) and on the 20th February 2014, due to the cold weather and the dry vegetation. About half of the total number was due to Poecilobothrus regalis (Meig.) – 591 specimens (54.17%).

According to Heydemann’s classification five groups of species are found (Table 1): eudominant - Poecilobothrus regalis (54.17%), dominant – Hercostomus thraciensis (13.38%), subdominant – Hercostomus plagiatus (8.52%), rare – Syn-tormon pallipes, Rhaphium caliginosum, Hercostomus nanus, Argyra leucocephala, Dolichopus salictorum, Sybistroma impar, Argyra argyria, Teuchophorus spinigerel-lus (very common in different types of ecosystems in the Upper Thracian Plain), and subrare – Gymnopternus metallicus, Campsicnemus simplicissimus, Chrysotus fem-oratus, Rhaphium pectinatum, Dolichopus nitidus, Rhaphium monotrichum, Sciapus frater, Micromorphus albiceps, Sympycnus pulicarius, Rhaphium auctum, Hercos-tomus convergens, Sybistroma nodicornis, Syntormon denticulatus, Teuchophorus cristulatus, Dolichopus griseipennis, Dolichopus nubilus, Chrysotimus molliculus, Medetera sp., Scellus notatus, Campsicnemus curvipes, Lamprochromus bifasciatus, Syntormon fuscipes, Syntormon mikii, Teuchophorus momacanthus. The species T. cristulatus was described with one male specimen from Sicily (Meuffels & Groot-aert, 1990). Another male specimen was found in the Asian part of Turkey (Tonguc et al., 2010). In the summer of 2011 Kechev collected insects along the banks of Tekirska River (around the town of Chirpan) and found three males of T. cristulatus (Kechev, 2012a). Both specimens discovered in this survey show that the species is widely distributed in this part of the Upper Thracian plain.

Analyzing number of species found per month and number of specimens per month (Fig. 4, 5), it can be concluded that during the period May-August the eco-system has the biggest numbers of species which could be easily explained by the weather conditions. June is the month with the highest specimens’ number mostly

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Table 1Number (ni – number of individuals in each species) and proportion (in %) of species

of Dolichopodidae found at Basha site

No Species

05/2

013

06/2

013

07/2

013

08/2

013

09/2

013

10/2

013

02/2

014

03/2

014

04/2

014

ni %

Eudominant

1 Poecilobothrus regalis 19 388 157 27 0 0 0 0 0 591 54.17

Dominant

2 Hercostomus thraciensis 91 0 0 0 0 0 0 0 55 146 13.38

Subdominant

3 Hercostomus plagiatus 35 33 1 19 4 1 0 0 0 93 8.52

Rare

4 Syntormon pallipes 0 33 2 0 3 7 0 0 0 45 4.12

5 Rhaphium caliginosum 4 6 7 7 2 0 0 0 4 30 2.75

6 Hercostomus nanus 23 0 0 0 0 0 0 0 0 23 2.11

7 Argyra leucocephala 0 0 4 10 5 0 0 0 0 19 1.74

8 Dolichopus salictorum 6 12 1 0 0 0 0 0 0 19 1.74

9 Sybistroma impar 0 1 14 4 0 0 0 0 0 19 1.74

10 Argyra argyria 7 5 0 1 0 0 0 0 3 16 1.47

11 Teuchophorus spinigerellus 0 0 0 10 0 1 0 0 0 11 1.01

Subrare

12 Gymnopternus metallicus 0 3 1 6 0 0 0 0 0 10 0.92

13 Campsicnemus simplicissimus 8 1 0 0 0 0 0 0 0 9 0.82

14 Chrysotus femoratus 2 6 0 0 0 0 0 0 0 8 0.73

15 Rhaphium pectinatum 0 1 3 0 1 1 0 1 1 8 0.73

16 Dolichopus nubilus 1 0 3 1 0 0 0 0 0 5 0.46

17 Rhaphium monotrichum 0 0 5 0 0 0 0 0 0 5 0.46

18 Sciapus frater 0 0 0 5 0 0 0 0 0 5 0.46

19 Micromorphus albiceps 0 4 0 0 0 0 0 0 0 4 0.37

20 Sympycnus pulicarius 3 1 0 0 0 0 0 0 0 4 0.37

21 Rhaphium auctum 0 0 3 0 0 0 0 0 0 3 0.27

22 Hercostomus convergens 0 0 2 0 0 0 0 0 0 2 0.18

23 Sybistroma nodicornis 2 0 0 0 0 0 0 0 0 2 0.18

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No Species

05/2

013

06/2

013

07/2

013

08/2

013

09/2

013

10/2

013

02/2

014

03/2

014

04/2

014

ni %

24 Syntormon denticulatus 0 0 0 0 0 1 1 0 0 2 0.18

25 Teuchophorus cristulatus 0 0 0 2 0 0 0 0 0 2 0.18

26 Dolichopus griseipennis 0 0 0 0 0 1 0 0 0 1 0.09

27 Dolichopus nitidus 0 0 0 1 0 0 0 0 0 1 0.09

28 Chrys otimus molliculus 0 0 0 1 0 0 0 0 0 1 0.09

29 Medetera sp. 0 1 0 0 0 0 0 0 0 1 0.09

30 Scellus notatus 1 0 0 0 0 0 0 0 0 1 0.09

31 Campsicnemus curvipes 0 0 0 1 0 0 0 0 0 1 0.09

32 Lamprochromus bifasciatus 0 0 0 1 0 0 0 0 0 1 0.09

33 Syntormon fuscipes 0 0 0 0 0 0 0 0 1 1 0.09

34 Syntormon mikii 1 0 0 0 0 0 0 0 0 1 0.09

35 Teuchophorus momacanthus 0 0 1 0 0 0 0 0 0 1 0.09

Fig. 4. Number of dolichopodid species found per month at Basha site

because of Poecilobothrus regalis and Hercostomus plagiatus from the dominant species group (Fig. 6) and Syntormon pallipes, Dolichopus salictorum, Rhaphium caliginosum, Argyra argyria from the group of rare species (Fig. 7). Sybistroma im-par shows its biggest number in July, Argyra leucocephala and Teuchophorus spini-gerellus – in August. The great number of subrare species found, although not so

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Fig. 7. Number of rare dolichopodid species found at Basha site

Fig. 5. Number of dolichopodid specimens found per month at Basha site

Fig. 6. Number of dominant (eudominant, dominant and subdominant) dolichopodid species found at Basha site

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abundant, show that maybe at the site the environmental conditions are good enough for those dolichopodid flies too but the relations and the interaction on the ecosystem level should be carefully examined in order to make any further statements.

It is worth noting that four of the species (Chrysotus femoratus, Hercostomus plagiatus, Rhaphium pectinatum and Lamprochromus bifasciatus) are newly record-ed to the fauna of Bulgaria. Hercostomus plagiatus falls in the group of subdominant species, while Chrysotus femoratus, Rhaphium pectinatum and Lamprochromus bi-fasciatus are subrare according to the current investigation findings (Table 1).

Calculations of the biodiversity measures as described in Material and Meth-ods section are made for the studied area and for other two described in some previous studies (Kechev, 2012b; Kechev et al., 2014) in order to make comparison (Table 2).

Species richness is the biggest in Basha site (as number of species found) but biodiversity indices taking into account the proportion of each species within the local aquatic community are the lowest. The Shannon-Wiener index is greater than 4 in Gradina Floodplain Forest showing greater richness and evenness of the community. In it there is no eudominant species, 2 dominant species, 5 subdominant species, 7 rare species and 10 subrare species (Table 3, Fig. 8). In Omurovska River site there are 1 eudominant species, 1 dominant species, 6 subdominant species, 5 rare species and 15 subrare species (Table 4, Fig. 8). The species found in three sites are 54 altogether as presented on Table 5 showing 12 species found only at Basha,

Table 2Dolichopodidae species richness, Shannon-Wiener Diversity Index and Simpson Index calculations

for three Bulgarian sites

Site SShannon-Wiener Diversity

Index Simpson Index

H’ Hmax E D 1-D 1/DBasha 35 1.84 3.56 0.52 0.32 0.68 3.10Gradina Flood-plain Forest 24 5.07 3.18 1.60 0.11 0.89 9.50

Omurovska river 28 2.37 3.33 0.71 0.16 0.84 6.13

Fig. 8. Dominance structure of dolichopodid flies in three Bulgarian sites

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Table 3Number and proportion of species of Dolichopodidae found at Gradina Floodplain Forest

No Species ni %Dominant

1. Gymnopternus metallicus 100 19.722. Dolichopus nubilus 86 16.96

Subdominant3. Syntormon mikii 45 8.884. Dolichopus salictorum 40 7.895. Teuchophorus spinigerellus 40 7.896. Hercostomus thraciensis 38 7.507. Dolichopus latilimbatus 35 6.90

Rare8. Hercostomus fulvicaudis 24 4.739. Campsicnemus simplicissimus 20 3.9410. Rhaphium caliginosum 15 2.9611. Sciapus frater 14 2.7612. Syntormon pallipes 12 2.3713. Poecilobothrus chrysosygus 9 1.7814. Poecilobothrus regalis 9 1.78

Subrare15. Campsicnemus curvipes 5 0.9916. Hercostomus convergens 4 0.7917. Chrysotus sp. 2 0.3918. Sybistroma nodicornis 2 0.3919. Syntormon metathesis 2 0.3920. Argyra leucocephala 1 0.2021. Dolichopus signifer 1 0.2022. Medetera sp. 1 0.2023. Sciapus platypterus 1 0.2024. Sybistroma setosa 1 0.20

7 species – only at Gradina Floodplain Forest, and 9 species – only in Omurovska river site. There are 5 common species for the three sites, 17 common species for Basha and Gradina, 11 common species for Basha and Omurovska, and 9 common species for Gradina and Omurovska. The number of subrare species is the biggest for the three sites, especially for Basha site (24) in comparison to Gradina (10) and Omurovska (15).

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Table 4Number and proportion of species of Dolichopodidae found at Omurovska River

Species ni %

Eudominant

1. Poecilobothrus regalis 98 35.25

Dominant

2. Sybistroma impar 30 10.79

Subdominant

3. Rhaphium caliginosum 26 9.35

4. Campsicnemus simplicissimus 16 5.76

5. Lamprochromus strobli 16 5.76

6. Teuchophorus monacanthus 16 5.76

7. Chrysotimus molliculus 15 5.40

8. Hercostomus gracilis 15 5.40

Rare

9. Syntormon denticulatus 10 3.60

10. Teuchophorus spinigerellus 7 2.52

11. Syntormon pallipes 4 1.44

12. Argyra leucocephala 3 1.08

13. Rhaphium auctum 3 1.08

Subrare

14. Rhaphium penicillatum 2 0.72

15. Sciapus platypterus 2 0.72

16. Sympycnus pulicarius 2 0.72

17. Syntormon triangulipes 2 0.72

18. Asyndetus latifrons 1 0.36

19. Campsicnemus curvipes 1 0.36

Fig. 9. Sørensen similarity index for dolichopodid flies in three Bulgarian sites

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20. Dolichopus discifer 1 0.36

21. Dolichopus griseipennis 1 0.36

22. Dolichopus signifer 1 0.36

23. Poecilobothrus chrysozygos 1 0.36

24. Sciapus wiedemanni 1 0.36

25. Syntormon filiger 1 0.36

26. Tachytrechus notatus 1 0.36

27. Teuchophorus medovoensis 1 0.36

28. Xanthochlorus tenellus 1 0.36

Table 5Summary of dolichopodid species found at the sites Basha, Gradina Floodplain Forest

and Omurovska River (species found only at one site and species found in the three sites are highlighted)

No Species Basha Gradina Flood-plain ForestOmurovska

River

1 Argyra argyria X

2 Argyra leucocephala X X X

3 Asyndetus latifrons X

4 Campsicnemus curvipes X X X

5 Campsicnemus simplicissimus X X X

6 Chrysotimus molliculus X X

7 Chrysotus femoratus X

8 Chrysotus sp. X

9 Dolichopus discifer X

10 Dolichopus griseipennis X X

11 Dolichopus latilimbatus X

12 Dolichopus nitidus X

13 Dolichopus nubilus X X

14 Dolichopus salictorum X X

15 Dolichopus signifer X X

16 Gymnopternus metallicus X X

17 Hercostomus convergens X X

18 Hercostomus fulvicaudis X

19 Hercostomus gracilis X

20 Hercostomus nanus X

21 Hercostomus plagiatus X

102

No Species Basha Gradina Flood-plain ForestOmurovska

River

22 Hercostomus thraciensis X X

23 Lamprochromus bifasciatus X

24 Lamprochromus strobli X

25 Medetera sp. X X

26 Micromorphus albiceps X

27 Poecilobothrus chrysosygus X X

28 Poecilobothrus regalis X X X

29 Rhaphium auctum X X

30 Rhaphium caliginosum X X X

31 Rhaphium monotrichum X

32 Rhaphium pectinatum X

33 Rhaphium penicillatum X

34 Scellus notatus X

35 Sciapus frater X X

36 Sciapus platypterus X X

37 Sciapus wiedemanni X

38 Sybistroma impar X X

39 Sybistroma nodicornis X X

40 Sybistroma setosa X

41 Sympycnus pulicarius X X

42 Syntormon denticulatus X X

43 Syntormon filiger X

44 Syntormon fuscipes X

45 Syntormon metathesis X

46 Syntormon mikii X X

47 Syntormon pallipes X X X

48 Syntormon triangulipes X

49 Tachytrechus notatus X

50 Teuchophorus cristulatus X

51 Teuchophorus medovoensis X

52 Teuchophorus momacanthus X X

53 Teuchophorus spinigerellus X X

54 Xanthochlorus tenellus X

103

The Sørensen similarity coefficient is calculated comparing the three sites (Fig. 9). The index has its biggest values for Basha and Gradina Floodplain forest (0.57). It is smaller and comparable to Basha and Omurovska river (0.38) and Gra-dina Floodplain forest and Omurovska river (0.37).

CONCLUSION

Along with the information provided about 35 dolichopodid flies collected in a small woodland and aquatic ecosystem, this study presents four new species (Chrysotus femoratus, Hercostomus plagiatus, Rhaphium pectinatum and Lampro-chromus bifasciatus) for the fauna of Bulgaria, as well as comparisons in different measures of diversity for the examined site and two other previously studied. The calculations of diversity indices show that at Gradina floodplain forest the richness and the evenness are greater than in other sites being under investigation too but the species richness is the biggest at Basha site showing also the greatest number of species found only at that site (12) when comparing to Gradina Floodplain Forest (7) and Omurovska River (9). The implications of the study lead to the conclusion that for diversity evaluations it is important to prove first the availability of a species in an ecosystem, then to examine it in terms of abundance and relations in the com-munity. Thus, the data presented show that there is a need of further investigation on the ecosystem level into the reasons of the geographical and seasonal distribution of dolichopodid species and the calculated diversity and similarity indices considering environmental factors’ influence.

Acknowledgements: Thanks to Dr Stoyan Georgiev from Agricultural University – Plovdiv for his help with the determination of plant species. The authors are also grateful to Mr Nikolay Genov and Mr Svetoslav Stoychev for their help during the collecting trips. Thanks are due to the anonymous referees, the editors of Silva Balcanica for their critical notes to the manuscript and to Mrs Ekaterina Arabska from the University of Agribusiness and Rural Development for her help in manuscript prepa-ration.

REFERENCES

Google earth V 7.1.1.1888. (June 6, 2012). Chirpan, Bulgaria. 42°10’37.49”N, 25°17’58.65”E, Eye alt 1.16 km. Cnes/Spot Image, DigitalGlobe 2013. http://www.earth.google.com [November 3, 2013].

Grichanov, I.Y. 2007. A checklist and keys to Dolichopodidae (Diptera) of the Caucasus and East Mediterranean. St. Petersburg: VIZR RAAS, Plant Protection News Suppl., 1-160.

Kechev, M. 2011. An improved check-list of Dolichopodidae (Diptera, Brachycera) of the fauna of Bulgaria. - In: Negrobov, O., V. Golub, S.Gaponov, V. Logvinovskii (eds.): Current Problems of Entomology, Voronezh State University, 73-78.

Kechev, M. 2012a. Long-legged flies (Diptera: Dolichopodidae) from the Upper Thracian Plain new to Bulgaria: Habitats and Distribution. Acta zoologica bulgarica, 64 (2), 205-208.

Kechev, M. 2012b. Diversity of Long-legged flies (Diptera: Dolichopodidae) in Gradina Floodplain Forest, Bulgaria. Acta zoologica bulgarica, Suppl. 4, 43-46.

104

Kechev, M., O. Negrobov. 2015. A new species of the genus Hercostomus Loew, 1857 (Diptera: Dolichopodidae) from Bulgaria. Acta zoologica bulgarica, 67(2), 199-202.

Kechev, M., O. Negrobov, I. Grichanov. 2014. Diversity of Long-legged flies (Diptera, Dolichopodi-dae) along the banks of the Omurovska river, with the description of a new species of the genus Teuchophorus Loew. Acta zoologica bulgarica, 66(3), 317-323.

Meuffels, H. J. G., P. Grootaert. 1990. A new species of Teuchophorus (Diptera, Dolichopodidae) from Sicily. Animalia (Catania), 17, 131-135.

Negrobov, O. 1991. Dolichopodidae. - In: Sóos, Á., Papp, L. (Eds.), Catalogue of Palaearctic Diptera. Vol. 7. Dolichopodidae-Platypezidae. Akadémiai Kiadó, Budapest, 11–139.

Pollet, M. 2004. Fauna Europaea: Dolichopodidae - In: Pape, T. (Ed.), Fauna Europaea: Diptera, Brachy-cera. Fauna Europaea version 2.4, http://www.faunaeur.org. [accessed on 20 December 2013].

Tonguç, A., I.Ya. Grichanov, H. Koç, O. Özgül, M. Barlas 2010. Contribution to the Dolichopodidae (Diptera) Fauna of Turkey. J. of Entomological Research Society, 12 (2), 103-107.

Yang, D., Y. J. Zhu, M. Q. Wang, L.L. Zhang. 2006. World catalog of Dolichopodidae (Insecta: Dip-tera). Beijing: China Agricultural University Press, 1-704.

E-mails: mkechev@gmail.com, agricollege.mivanova@gmail.com