QUALITATIVE COMPOSITION OF COMMUNITIES OF AQUATIC MACROINVERTEBRATES ALONG THE COURSE OF THE GOLIJSKA MORAVICA RIVER ( WEST-CENTRAL SERBIA )

As the largest and most significant river of the Moravica region, the Golijska Moravica river arises below the highest peaks of the Golija Mountains. Faunistic-ecological research on aquatic macroinvertebrates was carried out during 2003 and 2004. Macrozoobenthos communities of the Golijska Moravica had not previously been the subject of any hydrobiological studies, and this was the main reason why we conducted their systematic and complex investigation. A list of taxa of aquatic macroinvertebrates is presented and their qualitative composition analyzed. during the period of investigation, a total of 13 groups and 147 taxa were found.


IntroductIon
the composition of macrozoobenthos communities of the Golijska Moravica river duing the years 2003 and 2004 is analyzed in the present faunisticecological study.A total of 73 samples of the bottom fauna were taken along the entire length of the watercourse.complex investigation of macrozoobenthos in river ecosystems of Serbia from the faunistic and ecological aspects has been conducted before by B a r a č k o v (1973), Đ u k i ć (1975), Đ u k i ć et al. (1986,1992,1997), Đ u r k o v i ć et al. (1998), F i l i p o v i ć (1954,1957,1965,1966,1969,1976), J a k o v č e v (1983,1986,1989), J a n k o v i ć (1976, 1981, 1983a, 1983b, 1987, 1998), J o v a n o v i ć (1998), K a r a m a n (1964,1995,1998), K o n t a (1997), M a r i n k o v i ć -G o s p o d n e t i ć (1975), M a r k o v i ć (1995, 1998a, 1998b), M a r k o v i ć et al. (1997a,b, 1998, 1999), M a r k o v i ć and J a n k o v i ć (1986,1989), M a r k o v i ć and M i l j a n o v i ć (1995), M a r t i n o v i ć -V i t a n o v i ć et al. (1995, 1998a, 1998b), M i l j a n o v i ć (2001), M i t r o v i ćtu t u n d ž i ć (1973), o b u š k o v i ć et al. (1994), P a u n o v i ć et al. (1998,2003,2006), S i m i ć (1993,1996,1998), S i m i ć et al. (1993,1994,1997), S t a n k o v i ć et al. (1995), and Ž i v i ć et al. (2000,2001,2005).
the Moravica region has pronounced highland characteristics with distinctly broken relief.owing to a predominance of silicate rocks in the geological substrate, there are numerous springs of varying strength on the region's surface.the region is rich in rivers, rivulets, and mountain brooks (G a j i ć , 1989).Located in Western Serbia, it occupies an area of 3,116 km 2 , i.e., 3.41% of the area of Serbia (K o v a č e v i ć et al., 1997).
the largest river of this region is the Moravica or Golijska Moravica, which arises below a "ridge" of massifs where the Golija and Javor Mountains meet at the place called "Kozja Stena".the river is 98 km long and has a drainage area of 1 486 km 2 .density of the river's network within its watershed is high and comprises a value of 1 252 m/km 2 .the Moravica flows to the north and receives a considerable number of tributaries.the best-known righthand tributaries are the rivers Pakašnica, nošnica, Grabovica, and Ličanska reka. the most significant left-hand tributaries are the rivers Budoželjska reka, Lučka reka, Veliki rzav (Big rzav), and Mali rzav (Little rzav).
Brook trout (Salmo trutta L.) occurs throughout the entire length of streams belonging to the Moravica's watershed, i.e., it represents a clean salmonid region (report oI Ivanjica, 2005).
the Golijska Moravica is a right-hand tributary of the Western Morava.the confluence of the Moravica and Đetinja rivers gives rise to the Western Morava, whose total length is 211 km (G a v r i l o v i ć and d u k i ć , 2002).
the main purpose of the present work was to establish the qualitative composition of macrozoobenthos communities of the Golijska Moravica river and thereby make a significant contribution to our knowledge of the biodiversity of Serbia and neighboring regions.

MAterIAL And MethodS
the material for analysis was collected during 2003 and 2004.the entire length of the Golijska Moravica was investigated at a total of eight localities, from the source region to the lower part of the watercourse (Fig. 1).Material was collected every 20-25 days from november to the end of May.
the following parameters were determined on site: geographic coordinates, elevation above sea level, river width, average depth, throughput, and substrate type.data on geographic coordinates and elevation above sea level were assembled with a GPS hand station of the Garmin etrex type in the WGS 1984 system (with a measuring error of 6-10 m, 8 m on the average).river width was determined by means of visual estimation or by extending a graduated string from one bank to the other at places where it was possible to do so.depth was determined with a weighted graduated string or using data obtained from oI Ivanjica.the flow rate was determined by measuring the speed of movement of a leaf or small ball downstream over a known (i.e., measured) distance.

Sampling localities
I. Vučačka reka.together with numerous neighboring brooks on the slopes of the Golija Mountains, the stream Vučačka reka forms the Golijska Moravica river.Measuring 4 km in length, Vučačka reka has a channel width that varies from 2 to 4 m and depth of up to 90 cm.this torrential stream has a throughput of 1.2 m 3 /sec, elevation of 952 m a.s.l., and geographic coordinates of 43e 19' 88.3'' n and 20e 11' 33.4'' e. II.Golijska reka. the stream Golijska reka is a right-hand tributary of the Golijska Moravica.It is a watercourse of the torrential type with a length of 10 km, channel width of 4-7 m, and depth of 10-22 cm. the throughput of this stream is 0.94 m 3 /sec.elevation of the stream is 666 m a.sl., while its geographic coordinates are 43e 27' 36.8''n and 20e 13' 21.3'' e. III.Pakašnica.this stream is a right-hand tributary of the Moravica.A torrential watercourse with a length of 5 km, it has a channel width of 4-6 m, depth of up to 25 cm, and throughput of 0.98 m 3 /sec.the stream is at an elevation of 646 m a.s.l. and has geographic coordinates of 43e 28' 15.2'' n and 20e 14' 0.90'' e.
IV.A locality just below the place where the Pakašnica empties into the Moravica.Width of this part of the river's channel varies in the range of 5-7 m, its depth in the range of 15-30 cm. the river at this point has a throughput of 1.23 m 3 /sec.the given locality is at an elevation of 638 m a.s.l. and has geographic coordinates of 43e 28' 28.5'' n and 20e 14' 46.2'' e.
V. the rimski Most locality on the Moravica.the channel on this part of the watercourse is 6-7 m wide and has a depth ranging from 15 to 32 cm. the stream here has a throughput of 1.3 m 3 /sec.Lying at an elevation of 629 m a.s.l., this locality has geographic coordinates of 43e 28' 13.3'' n and 20e 14' 08.2'' e.
VI. the Međurečje locality on the Moravica.the river's channel here has a width ranging from 6.5 to 9 m and depth that varies from 15 to a maximum value of 140 cm. the Moravica's throughput at this locality is 0.93 m 3 /sec.At an elevation of 556 m a.s.l., the locality's geographic coordinates are 43e 31' 16.2'' n and 20e 13' 28.9'' e.
VII. Pećine, a settlement on the Moravica between the Međurečje locality and the town of Ivanjica.the channel is 13 to 26 m wide here, and depth varies from 15 to 95 cm. the river's throughput is 0.95 m 3 /sec.Lying at an elevation of 512 m, Pećine has geographic coordinates of 43e 32' 38.2'' n and 20e 15' 19.0'' e.
VIII.Senjak, a place on the Moravica between the towns of Ivanjica and Arilje.Width of the channel hare ranges from 7.5 to 18 m.the river's depth varies from 35 to 40 cm, while its throughput is 2.83 m 3 /sec.this locality lies at an elevation of 442 m a.s.l. and has geographic coordinates of 43e 36' 20.2'' n and 20e 12' 15.5'' e. Biological material, i.e., samples of the bottom fauna, was collected using standard sampling procedure.A total of 73 samples were collected.A hand-held benthos net with mesh size of 500 μm was used to collect qualitative samples.Sampling with the aid of this net was carried out by a combined procedure involving stirring the bottom up by foot and collecting the disturbed material with the net (the "kick and sweep" technique).Macrozoobenthic organisms were also collected individually by hand and rinsed to get rid of particles of various solid substrates.to ensure habitat heterogeneity or multihabitat sampling, samples were taken from different substrate types, then combined in a single composite sample.Immediately after sampling, the biological material was immersed in 4% formalin on site for preservation.
Further processing of the collected and conserved material was carried out in the Laboratory of hydrobiology, department of hydroecology and Water Protection, Siniša Stanković Institute for Biological research, Belgrade.Analysis of representatives of the bottom fauna was performed with the aid of binoculars from carl Zeiss with magnification of 0.63-6.3xand an olympus 235536 binocular microscope with ocular magnification of 10x and objective magnification of 10, 40, and 100x.the collected macrozoobenthic organisms were identified  the following groups were best represented in composition of the community of macroinvertebrates: ephemeroptera, trichoptera, oligochaeta, Plecoptera, chironomidae, diptera, and coleoptera.the other identified groups (nematoda, turbellaria, hirudinea, Gastropoda, Amphipoda, odonata, and heteroptera) were found in a small number of samples.
the number of taxa at individual localities ranged from 17 (at locality 1) to 94 (at locality 3) taxa.
In regard to dominance, the species Leuctra fusca (Plecoptera), Rhitrogena semicolorata, and Baetis vernus (ephemeroptera) Ibisia marginata and Riolus cupreus (coleoptera) were constant in the bottom fauna of the Golijska Moravica throughout the two-year period of investigation.At all the described localities, the insect component was best represented and characterized by the greatest of groups.Increased representation and diversity of members of the groups oligochaeta and diptera (especially the family chironomidae) was recorded at the downstream loclities 7 and 8. there the river's current slows down, the channel widens, sedimentation is greater, and soft types of substrate (silt and sand) are present to a greater extent, all of which together contribute to alteration of the qualitative composition of macrozoobenthos communities in favor of oligochaeta and chironomidae.dIScuSSIon A total of 147 taxa from 13 groups were found during two-year investigation of the Golijska Moravica river.
With respect to the nature of its current and physico-chemical characteristics, the Golijska Moravica belongs to the category of distinctly ritronic watercourses.throughput values vary from 0.93 to 2.83 m 3 / sec, which puts the investigated watercourse in the group of fast streams and corresponds to the range (0.6-3.5 m 3 /sec) given by We t z e l (1975) as the framework within which rheophilic organisms of the bottom fauna can remain firmly fixed to the substrate.
dominant in the composition of macrozoobenthos communities of the investigated watercourse were larvae of the insect groups ephemeroptera, trichoptera, Plecoptera, chironomidae, diptera, coleoptera, and heteroptera.Such a nature of macrozoobenthos communities was dictated by the varied composition and structure of the bottom substrate, as well as by suitable features of the terrain and characteristics of the river's current.In comparison with Serbian highland streams whose macrozoobenthos communities have been analyzed to date (B a r a č k o v, 1973; K o n t a , 1997; M a r k o v i ć , 1995, 1998a, 1998b , 1998; S i m i ć , 1993; S i m i ć et al., 1994, 1997, 2003, 2006; Ž i v i ć et al., 2005), the Moravica river does not differ significantly, i.e., larvae of insect groups are dominant in it.
the animal population of the investigated highland stream is diverse and rich.the bottom fauna is characterized by special life forms that are adapted to conditions of fast water: a flattened body shape, as in Ecdyonurus sp. and Epeorus sp.(ephemeroptera), Dugesia sp.(turbellaria), Perla sp.(Plecoptera), Elmis sp.(coleoptera), and Ancylus sp.(Gastropoda); and close adherence to the substrate, as in Sericostoma sp., Glossossoma sp., Goera sp., and Lepidostoma sp.(trichoptera) and members of the family chironomidae.
Structure of the bottom fauna is highly varied.occurring most frequently are macrozoobenthos communities of the lithorheophilic type (ephemeroptera, trichoptera, Plecoptera, coleoptera, Amphipoda, Gastropoda, and turbellaria), followed by ones of the psammorheophilic (nematoda, chironomidae, certain representatives of ephemeroptera and Plecoptera, and Spirosperma of the group oligochaeta) and psam-mopelorheophilic (oligochaeta, chironomidae, and certain representatives of trichoptera) types.the insect groups found at downstream localities, e.g., ephemeroptera, trichoptera, diptera, and coleoptera, together with the groups oligochaeta and chironimidae, characterize the macrozoobenthos communities collected on the Moravica river at the beginning of november of the year 2003.certain representatives of the groups ephemeroptera, oligochaeta, and chironomidae were represented at the end of november of the same year.Bottom fauna samples collected in the middle of december of 2003 along the course of the Moravica river were characterized by the presence of the species Baetis vernus and Rhitrogena semicolorata (ephemeroptera), in addition to the species Psammoryctides albicola of the group oligochaeta and representatives of chironomidae.
the best represented forms in bottom fauna samples collected during the winter of 2004 were the species Rhitrogena semicolorata, Baetis vernus, and Ephemera danica from the group ephemeroptera, followed by Brachyptera risi from the group Plecoptera; Psammoryctides albicola, Limnodrilus hoffmeisteri, and Nais elinguis from the group oligochaeta; Lepidostoma sp.(trichoptera); and representatives of chironomidae.Along the entire course of the Moravica, bottom samples collected in the spring were characterized by dominance of representatives of the groups Plecoptera (Protonemura meyeri), ephemeroptera (Rhitrogena semicolorata, Ephemera danica, and E. vulgata), trichoptera (Sericostoma sp.), coleoptera (Riolus cupreus), oligochaeta (Propappus volki, Lumbriculus variegatus, Nais elinguis, Limnodrilus hoffmeisteri, and L. claparedeanus), and chironomidae.the ecological characteristics and living requirements of representatives of the bottom fauna groups collected along the watercourse dictate a pattern of constant seasonal dynamics.numerous bottom fauna groups were present during both the autumnwinter and spring periods, i.e., throughout the entire period of investigation of the Moravica river, and the insect component played a significant part in formation of characteristic macrozoobenthos com-munities of the given river as a highland stream.
In the course of the conducted investigation, we identified both macrozoobenthos representatives that were here found for the first time in the waters of our country, i.e., species new to the fauna of Serbia (Tatriella slovenica hrabĕ, 1936; and Baetis alpinus Picte, 1843); and ones that according to I l l i e s (1978) have to date been rarely found in this part of the Balkan Peninsula (Acylus fluviatils Müller, 1774; and Dinocras cephalotes curtis, 1827).
In addition to this, the presence of forms that according to t i m m ( 1980

Fig. 1 .
Fig. 1.Localities where sampling of the bottom fauna was conducted in the Golijska Moravica river (map scale of 1:100,000 c oziexplorer 3.93.3b).
; M a r k o v i ć et al., 1997, 1998; M a r k o v i ć and M i l j a n o v i ć , 1995; o b u š k o v i ć et al., 1994; P a u n o v i ć et al.

Table 1 .
List of taxa of aquatic macroinvertebrates of the Golijska Moravica River.