Hexarthra jenkinae (de Beauchamp, 1932)

Mis, Didem Özdemir, Ustaoğlu, Mustafa Ruşen, Online, Published & Version, Final, 2017, Distribution of rotifers of high mountain lakes in the Eastern Black Sea Range of Turkey, Turkish Journal of Zoology 41 (3), pp. 674-685 : 680-682

Hexarthra jenkinae (de Beauchamp, 1932)

Familia: Filiniidae

Filinia longiseta (Ehrenberg, 1834)

Filinia terminalis (Plate, 1886)

Ordo: Collothecaceae

Familia: Collothecidae

Collotheca sp.

A list of the 63 rotifer taxa collected from the study area is given in Table 4. Notholca squamula (46 stations, 77.97%), Keratella quadrata (44 stations, 74.58%), Lecane lunaris (38 stations, 64.41%), Euchlanis dilatata lucksiana (29 stations, 49.15%), Lepadella patella (25 stations, 42.37%), and Lecane flexilis (18 stations, 30.51%) were the dominant species.

The rare taxa ( Asplanchna priodonta , Brachionus quadridentataus , Collotheca sp. , Conochilus dossuaris , Dissotrocha macrostyla , Euchlanis deflexa , Euchlanis incisa , Euchlanis lyra , Hexarthra cf. bulgarica , Keratella valga , Lecane clara , Lecane hamata , Lecane kluchor , Lecane latissimi , Lecane quadridentata , Lecane stichaeta , Lepadella triptera , Mytilina ventralis brevispina , Testudinella mucronata , Testudinella patina , Trichocerca rattus , Trichocerca tenuior , Trichocerca vernalis ) were observed in only one station (lake) (1.69%) each ( Table 4).

The highest number of taxa was found in the lakes in Fırtına Stream (39 taxa) and the lowest number of taxa in Lake Arhavi Karagöl (Kabisra Stream) (7 taxa) ( Figure 4 ).

Based on the saprobic system ( Sladecek, 1973), the rotifer taxa were evaluated as follows: 54% oligosaprobic (o), 26% oligosaprobic/beta-mesosaprobic (o-β), 16% beta-mesosaprobic (β), and 4% beta-mesosaprobic/ oligosaprobic (β-o). We propose that 80% of the rotifer taxa were indicators of oligotrophic conditions and the remaining 20% were indicators of mesotrophic conditions ( Figure 5).

When the dendrogram, which gives the similarities of the examined localities, was created, the stations named İ7 and F21 had obvious differences that caught our attention when they were compared with other stations. Moreover, a station named K1 closely shared features with those two stations. Concerning the variety of species, the most similar localities are the stations coded İ11 and İ3. Similar to those, the stations coded İ8 and F6 also have various similarities concerning the variety of species. In other localities, the rates of similarity are about 70% or lower (Figure 6).

When altitudes of the lakes that we studied and rotifer species diversity were compared, a decrease was not observed in species diversity as altitude increased ( R 2 = 0.067) (20 species in Lake Uzungöl with an elevation of 1100 m and 4 species in Lake Deniz with an altitude of 3370 m) ( Figure 7 ) .

70

60

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N 30

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β-o; 4

β; 16

o; 54 o-β; 26

0 Çoruh Fırtına İy dere Kab sra Maçka Solaklı Total Bas ns

Percent S m lar ty

Figure 6. UPGMA dendrogram illustrating the relationship of rotifers in studied lakes.

Figures

Figure 4. Taxa distributions of rotifers in the studied lakes.

Figure 7. Rotifer species richness for different altitudinal distributions of lakes (n = 58) except Lake Uzungöl (1100 m a.s.l.).