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New records of Chironomus MEIGEN species (Diptera, Chironomidae) in the Novohradské Mountains (South Bohemia)
Matěna, Josef ; Matěnová, V.
C. longistylus Goetghebuer and C. sp. South Bohemia were found as new species for the Czech Republic. Karyotype of the new species is presented together with preliminary mapping of chromosomal arms A, C, D, E, F. C. cingulatus, melanescens, nuditarsis, uliginosus and C. (Camptochironomus) palidivittatus are recorded for the first time from Novohradské Mountains. Notes about distribution and ecology of these species are given.
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The occurrence of brook lamprey [Lampetra planeri (BLOCH, 1784)] in Novohradské Mountains (South Bohemia, Czech Republic)
Matěnová, V. ; Matěna, Josef
The occurrence of brook lamprey was studied in Novohradské Mountains during 1999-2003. Altogether 83 profiles on 22 second to fourth order brooks and streams were fished by means of electroshockers. The area investigated can be divided into three basins. Significant differences were found between basins with respect to frequency of occurrence and density of lamprey populations. The highest frequency of occurrence was in the Stropnice River basin (6 streams of 8 investigated, average abundance 2598 inds ha-1), followed by the Malše River (4 streams of 8 investigated, average abundance 844 inds ha-1). In the Černá Rivulet basin only in 1 of 6 streams investigated the brook lamprey was found at very low densities - 28 inds ha-1 on average. The lamprey contributed substantially to the whole forming more than 50
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The genus .i.Chironomus./i. MEIGEN (Diptera, Chironomidae) in the Novohradské Mountains (South Bohemia)
Matěna, Josef ; Matěnová, V.
The occurrence of Chironomus species was investigated in Novohradské Mountains during 1999-2001. Fishponds, running waters and small standing waters of both permanent and astatic characters were included. Larvae were identified cytotaxonomically according to polytene chromosomes of salivary glands. Ch. annularius occurred more regularly in fishponds without fishery management, further species were found only in some of these habitats - Ch. balatonicus, bernensis, obtusidens, parathummi, plumosus, sp. - near muratensis and Ch. (C.) tentans. Organically polluted stretches of running waters were characterized by mass occurrence of Ch. riparius. Ch. luridus and Ch. melanotus were the dominant species of small permanent water bodies, further species found in these habitats were Ch. aberratus, commutatus, dorsalis, holomelas, piger and pseudothummi. Astatic habitats - rainpools were inhabited almost exclusively by Ch. dorsalis.
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Ichtyofauna of the border Malše River
Matěnová, V. ; Matěna, Josef
Ichthyological investigation of the border section of the Malše River was performed in 2002 and 2003. The occurrence of brook lamprey larvae and five rheophilous fish species was confirmed – brown trout, common sculpin, grayling, burbot, stoneloach. Species escaping from fishponds – perch and common carp were found in negligible numbers. The brown trout dominated in numbers at all investigated profiles. The length and age analysis of the brown trout population showed the dominance of YOY fish, the population exhibited a harmonical age class composition. Results confirmed successful natural reproduction of trout, grayling, burbot and bullhead. The following investigation in 2003 oriented specially on the occurrence of brook lamprey proved that the population remained unaffected by the floods in 2002. The border Malše River represents an athropogenically slightly affected watercourse with suitable conditions for natural reproduction of all indigenous species found during the study.
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