variaBLe morphoLogy: first record in the repuBLic of montenegro

Abstract The genus Lemanea and a species belonging to this genus, Lemanea fucina Bory 1808, are reported for the first time in the republic of montenegro (southeast europe, in the river Tara, at one locality “Splavište” (n-43° 07’ 721”, e 019° 18 ‘609”). This is a new finding, and also the southernmost point of occurrence of this species in europe. The species is characteristic mostly for rivers of the countries of northern and western europe. The variable morphological characteristics of this species are described and illustrated in this work.

The aim of this work is to provide the latest information on the new findings of L. fucina from the republic of montenegro, as well as the data on the ecology and morphology of this species.
Samples were fixed immediately in 4% formaldehyde.The following environmental variables were measured for each sampling site: temperature (°C), current velocity (cm s-1 ), ph, oxygen concentration (mg l -1 ), saturation of oxygen (%), conductivity (measured with a digital conductometer of the hA-nAeP-3 type and expressed in μS cm -1 ), depth (cm) and type of substratum.In addition, the percentage cover of the alga on the substratum was estimated for the sampling site.Preserved material is stored in the collection of the Department of Biology and ecology in Kragujevac, Serbia.For taxa identification the material was magnified 160-640 times and analyzed with a Carl Zeiss-Amplival microscope.
In the laboratory we recorded the following morphological characteristics: presence of a stalk, presence and incidence of branched plants, plant length, nodal diameter (nD), internodal diameter (ID), presence of axial cortical filaments, arrangement of spermatangial sori, length and diameter of carpospores, presence of a Chantransia stage; length and diameter of cells of Chantransia (vis and Sheath, 1992;Sheath et al., 1996;Kumano, 2003).

reSULTS AnD DISCUSSIOn
Plants of Lemanea fucina were found in sections of the river Tara where the riverbed is 10-20 m wide.Thalli were found on calcareous big stones in sunny sites, at 0.5-1 m depth, water temperature 10.9°C, current velocity 50-70 cm s -1 , ph 8.4, conductivity 202 μS cm -1 , oxygen concentration 9.76 mg l -1 , and saturation of oxygen 96.6%.Percentage coverage varied between 1% (may 2007) and 5% (may 2009).Samples were found in community with Nostoc coeruleum (Lyngbye) Bornet and Flahault.On a grownup thallus and the Chantransia stage, Chamaesiphon incrustans is a common epiphyte.
The morphological and anatomical characteristics of the L. fucina found in the river Tara are summarized in Table 1.The plants were found growing individually or in tufts.The height was from 1.5 to 16 cm.(Fig. 1-2).Olive-green to purple-green in color.non-branching to densely branching (up to 19 branches), thalli narrowing towards the top into thin threads of capillary appearance, whose width is only 10 μm.At the base, they have a thin cylindrical stem 1.5 -2cm wide; stalk diameter from 180 to 320 μm.The diameter of node is from 280 to 700 μm, and of the internode from 160 to 510 μm (node : internode ratio is 1.4).The number of spermatangial papillae in the node is from 2 to 7, most often 4.There is no cortex around the central axis cell.The length of carpospores is from 13.2 to 33.3, and diameter from 8 to 19.8 μm.The primary stadium (Chantransia stage) was found at the base of the stalk.Its height is from 231 to 386 μm, cloddy, branching, with no hairs on top.The cells are 39.6 to 62.7μm long and 9.9 to 19.8 μm wide (length: width ratio from 4.4 to 7.6).monosporangia are unknown.
By comparing these characteristics of L. fucina as well as the presence and appearance of the Chantransia stage on them, it was noticed that this alga shows considerable differences in morphological appearance during the same period of the year at the same locality and the same period of the life cycle (Table 1).There is congruence with the basic diagnostic characteristics of the species L. fucina Bory 1808 (Kumano 2003;john et al., 2008) and L. mamillosa Kützing 1845 (Kumano, 2003) (Table 1).Thalli were individual in may 2007 (diagnostic characteristic of L. fucina), in tufts in may 2009 (characteristic of L. mamillosa); the number of sec- Based on the analysis of the existing works dealing with the characteristics and taxonomic status of the species L. fucina Bory and L. mamillosa Kützing and their synonyms (Table 1), it is concluded that there are numerous problems related to the taxonomy of the entire genus and species and no clear consensus among researches.In light of available data, the authors have retained the name of this species Lemanea fucina Bory.