CONSPECT OF THE CLADOCERAN SPECIES...

Romanian Journal of Aquatic Ecology 1.1 (2011)

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CONSPECT OF THE CLADOCERAN SPECIES

(CRUSTACEA, BRANCHIOPODA)

IDENTIFIED IN THE POORLY KNOWN URBAN TINERETULUI LAKE

(BUCHAREST, ROMANIA)Ştefan NEGREA 1 and Oriana HURDUGAN-IRIMIA 2

Keywords: urban limnic ecosystem, cladocerans, taxonomy, ecology,

zoogeography.

Abstract

The paper presents the cladoceran species (Crustacea, Branchiopoda) found in

the Tineretului Lake of Bucharest, an urban lake founded 40 years ago from a

rheocrene swamp and underestimated by specialists, no limnology studies being

carried yet on this water body. During two years (October 2007 - October 2009)

zooplankton samples were taken every month, in which 12 species of cladocerans

were identified, belonging to two orders, Anomopoda (11 species) and Ctenopoda

(1 species). Each species is briefly presented with an up to date taxonomical status,

with chorological references and ecological data resulting from the analysis of the

physical and chemical parameters measured in the Tineretului Lake. The quality of

bioindicator species was mentioned were necessary. For many species the pH

tolerance limits are higher than those mentioned in the literature. Three of the

species and subspecies were found for the first time in the Romanian Plain

region (Camptocercus uncinatus, Chydorus sphaericus caelatus and Alona costata). The

paper closes with some considerations regarding the species indicating the good

water quality of the lake and a possible explanation of the relatively small number

of species from this lake rich in submerged vegetation compared with other

Romanian eutrophic plain lake.

Résumé: Les espèces de Cladocères (Crustacea, Branchiopoda) identifiées dans

un lac urbain méconnu, le lac Tineretului (Bucarest, Roumanie).

Dans cet article sont présentées les espèces de cladocères (Crustacea,

Branchiopoda) trouvées dans le Lac Tineretului de Bucarest, un lac intra urbain

aménagé il y a 40 ans à partir d’un marécage d’origine rhéocrène et pas encore étudié

par les limnologistes, malgré sa richesse faunistique. Pendant deux and (d’Octobre

2007 en Octobre 2009) des échantillons mensuels de zooplancton ont été prélevés,

Rom. J. Aquat. Ecol. 1.1 (2011); Ş. Negrea & O. Irimia – Tineretului Lake Cladocerans, pp. 121-138

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dans lesquels 12 espèces de cladocères ont été identifiées, appartenant à deux

ordres, Anomopoda (11 espèces) et Ctenopoda (1 espèce). Chaque espèce est

brièvement présentée, avec un état taxonomique à jour, des références chorologiques

et des données d’ordre écologique résultant de l’analyse des paramètres physiques

et chimiques mesurés dans le Lac Tineretului. La qualité d’espèce bio indicatrice a

été indiquée là où a été le cas. Pour beaucoup d’espèces, les limites de la tolérance

pH sont plus grandes que celles indiquées dans la littérature. Trois des espèces et

sous-espèces ont été trouvées pour la première fois dans la région de la Plaine

Roumaine (Camptocercus uncinatus, Chydorus sphaericus caelatus and Alona costata).

L’article se termine avec quelques considérations sur les espèces de cladocères

indicatrices de la bonne qualité de l’eau du lac et une possible explication pour le

nombre relativement bas des espèces de ce lac riche en végétation submergée

par comparaison avec d’autres lacs eutrophs de plaine de la Roumanie.

Rezumat: Conspectul speciilor de cladocere (Crustacea, Branchiopoda)

identificate într-un lac intraurban nestudiat, Lacul Tineretului (Bucureşti, România).

Sunt prezentate speciile de cladocere (Crustacea, Branchiopoda), găsite în

Lacul Tineretului din Bucureşti, un lac intraurban, amenajat cu 40 de ani în urmă

dintr-o mlaştină de origine reocrenă, şi încă nestudiat de limnologi, în ciuda bogăţiei

sale faunistice. Pe parcursul a doi ani, (octombrie 2007 - octombrie 2009), au

fost prelevate lunar eşantioane de zooplancton, în care au fost identificate 12 specii

de cladocere, aparţinând la două ordine, Anomopoda (11 specii) şi Ctenopoda (1

specie). Fiecare specie este prezentată succint, cu statutul taxonomic la zi, cu referiri

la chorologie, precum şi cu date de ordin ecologic, rezultate din analiza parametrilor

fizico-chimici, măsuraţi în Lacul Tineretului. S-a menţionat calitatea de specie

bioindicatoare, unde a fost cazul. La multe specii, limitele toleranţei la pH sunt mai

mari decât cele menţionate în literatura de specialitate. Trei dintre specii şi subspecii

au fost găsite, pentru prima oară, în Câmpia Română (Camptocercus uncinatus,

Chydorus sphaericus caelatus şi Alona costata). Lucrarea se încheie cu câteva

consideraţii privind speciile de cladocere indicatoare a bunei calităţi a apei, din

Lacul Tineretului şi cu o posibilă explicaţie a numărului relativ redus de specii din

acest lac, bogat în vegetaţie submersă în comparaţie cu alte lacuri eutrofe de câmpie

ale României.


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Introduction

The Tineretului Lake in Bucharest is a poorly known urban lake, in spite of

the rich biocenosis that inhabits it. Although an artificially modeled lake, it is fed

by natural sources, meaning several subterranean springs in its narrow NW end as

well as by precipitations. It discharges through a pipeline into the collector stream

of Dâmboviţa at an estimated flow of 24,911.66 ft3/h (6.855 m3/s). The lake has a

surface of approximately 13 ha and an average depth of 1.9 m, with measured

depths ranging from 0.5 m to 3.1 m. From October 2007 to October 2009 monthly

sampling campaigns took place, measuring the physical and chemical parameters

and identifying the cladoceran fauna of the lake. During this period, the lake has

frozen over in January 2008 and from March to April 2008 it was visited by

migratory water fowl.

In the same spring period, the lake was almost completely covered with a

very rich present macrophytic association, Potamogetoneto-Myriophylletum spicati.

On the 4th of May in 2008, this rich vegetation was harvested and removed from

the lake area. From this period on, during the warm season, the lake suffered of

a large phytoplankton bloom that altered its chemical and physical parameters.

All the surveyed physical and chemical parameters have gradually returned to the

normal values in September 2008. The situation was repeated the following year,

2008-2009.

Materials and Methods

The cladoceran fauna was sampled by qualitative methods, with the use of a

planktonic net, Ø17 cm, 35 cm long, with a 0.65 mm mesh, in different fixed sampling

stations as well as in transects of the superficial layer carried on the entire length of the

lake (1070 m) (Fig. 1).

The fixed stations were chosen from different ecological qualities: macrophytic

submerged vegetated substrata, barren muddy substrata, floating trunks used as resting

space by waterfowl and turtles, populated by filamentous algae, barren concrete lake

banks, also populated by filamentous algae. In order to sample the vertical profiles and

the muddy substrata, we used a weight-pulled planktonic net. Each sample is formed of

three consecutive complete profiles of the same station, from the bottom up to the

surface.


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Fig. 1 - Sampling schedule of the Tineretului Lake, Bucharest (Photo Google Earth,

2007). TA - Actors Teraces, PE - Fishing Farm; Artificial islands made of floating logs =

stations 2 and 4, sampling points = stations 1 - 6. I - western sector of the lake,

closer to the subteranean springs, II - eastern sector of the lake.

For floating trunks and concrete banks we used a plastic scraper to scrape around

10-15 cm2 of the filamentous algae that were swapped on the planktonic net and bottled.

The macrophytic vegetation was collected (2-3 entire plants, up to 2 m long) and

washed in the planktonic net. We also collected floating debris, like feathers, dead

leaves, empty plastic containers that were washed in the net separately.

We also sampled the temporary water pools from the two main islands of the

lake, 10-20 cm deep, situated on rich humic substrata. All the samples were fixed with

formaldehyde 40% used to obtain a final concentration of 4% formaldehyde.

The identification of the species was made according to the identification keys of

Negrea (1983) and Van Damme et al. (2010) for the Alona genus and the classification is

according to Dumont & Negrea (2002). Photos 2 - 13 are made by the second author

using a Sony digital camera adapted to a Zeiss microscope and a Zeiss binocular

magnifier. The body contour and the morphological characters were enhanced by the

first author on all photos.


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As the ecological aspect is one of the main concerns of the present study/article,

the sampled specimens were photographed in a glass dish with the natural material

on which they were collected, instead of being isolated and photographed separate on a

slide.

Results and Discussions

So far, twelve cladocerans species have been identified, belonging to

the Anomopoda order, with one exception, Sida crystallina of the Ctenopoda order.

All the identified cladocerans are planktonic, phytophylic species, except Ilyocryptus

agilis and also Macrothrix laticornis, illiophylic and benthic species. The identified

species and subspecies are presented below (all taxa are presented in alphabetical

order).

Phyllum CRUSTACEA

Class BRANCHIOPODA

Superorder CLADOCERA

1. Order ANOMOPODA

1.1. Family BOSMINIDAE

1.1.1. Bosmina longirostris (O. F. Müller, 1785) (Fig. 2)

According to Negrea (1983), this species is mostly planktonic and frequent in the

Romanian Plain region. Other authors (Jeppesen et al., 1998), describing the species in

different world ecosystems, consider that the species is equally macrophytophylic as it is

planktonic.

In the Tineretului Lake, this species was collected in the open water as well

as in the epiphyton covering the submerged willow logs that serve as bird refuge

in the NW end of the studied lake. The species registered two density maximums,

one during the spring period (March and April 2008) and the other during the

autumn period (August and October 2008 and 2009) in the open water samples as

well as an autumn maximum in the Miriophyllum spicatum samples (27.10.2007).

Meanwhile, the transect samples did not recorded any of the planktonic cloudes

usually formed by the individuals of this species. The two density peaks contained

two different morphs, B. longirostris f. typica in the spring samples and B. longirostris

f. similis in the autumn samples, accompanied by an yearlong morph, B. longirostris

f. cornuta.


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a) b)Fig. 2 - Bosmina (Bosmina) longirostris f. cornuta. a. female with two embrios

and b. male collected in transect sampling of 28.10.2007 in the Tineretului Lake.

First mention for the Romanian Plain: in a plankton sample from the fish pond of

Pipera area, Bucharest (Buşniţă & Luca, 1938, cited by Negrea, 1962, p. 435 and 485).

1.2. Family CHYDORIDAE Dybowski & Grochowski, 1894 emend. Frey, 1967

A. Subfamily ALONINAE Dybowski & Grochowski, 1894 emend. Frey, 1967

1.2.1. Alona affinis (Leydig, 1860) (Fig. 3a)

Negrea (1983) considers that the Romanian populations belong to the Alona

affinis ornata subspecies, sensu Smirnov 1971, although most of the recent authors are

reticent, considering the fact that the European populations to belong to the type species,

Alona affinis, as the original material for the Alona affinis ornata was described from

lake Titicaca by Stingelin and not reexamined since 1895 (Van Damme et al., 2010).

Acording to Negrea (1983, p. 337), in Romania the species is eurthermal (8-

26˚C), favouring the large shallow waters, the dead meanders and the very slow flowing

river arms from the Danube inferior flood plain and the Danube Delta as well as the

glacial lakes of the Southern Carpathians and some mountain reservoirs. It is less

frequent in some deep lakes and big rivers. Only exceptionally found in saline lakes and

temporary pools. Predilection biotopes are: emerged vegetation periphyton, open water

within vegetation patches, submerged, floating vegetation. Shore lines with rich detrital

matter or filamentous algae within the proximity of macrophytic vegetation. In the

Carpathians it is mentioned up to 2040 m of altitude (the glaciar lakes of Bucura and

Bâlea). It is cited from March to December. Negrea (1983) mentions the pH limits to be

5 - 7.7. Cosmopolitan species, found everywhere in Europe.


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a) b)Fig. 3 - a) Alona affinis. Female with 2 embrios collected in Tineretului Lake in April

2008; b) Alona costata. Female with one embrio, decomposing specimen collected in

April 2008.

In Tineretului Lake, the species was frequent, never dominant, found in plankton

from April to October in epiphyton and in macrophytic samples in the first half of

March. Most of samples had a pH of 8-8.3.

First mention for the inferior Danube sector: as Alona affinis by Spandl (1926) in

the inferior Danube River region, in lakes and channels of Insula Brăilei. First mention

for the Romanian Plain: Negrea (1983) in the Snagov Lake, as Biapertura affinis.

1.2.2. Alona costata Sars, 1862 (Fig. 3b)

Macrophytophylic species, preferes the flooded plains and the Danube Delta with

shallow and vegetated water surfaces. Less frequent in the rest of the Romanian territory

(Negrea, 1983). It dwells only in the emerged, floating and submerged vegetation

patches and in the open water spaces within. According to Negrea (1983) the species is

present from February to November, the maximum density being reached in June and

July in the Potamogeton patches.

In the Tineretului Lake the species was present in January 2009 as well as in

April, May and in October samples.

First mention for the Romanian Plain: Tineretului Lake, Bucharest (Hurdugan-

Irimia, 2008).

1.2.3. Camptocercus uncinatus Smirnov 1971 emend. Negrea 1982 (Fig. 4. a-b)


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Rare species, never dominant, as the other representatives of its genus. The

species is considered by Smirnov (1998) as benthic, present in Europe, the eastern and

the southern limits of its areal being yet to be discovered. Negrea (1983) identified the

species only from pools and shallows from the flooded plain of the Danube and the

Delta. The species is generally connected to macrophytic habitats and found in the

aquatic vegetation, emerged, submerged or floating, on the silt bottoms and in

filamentous algae patches. Found by Negrea (1975) at a pH = 7.1 - 7.4, it was collected

in the Tineretului Lake at pH = 8.

First mention for the Romanian Plain: this is the first citing of the species for the

Romanian Plain region, with one specimen found in a Myriophyllum sample from May

2008 in the Tineretului Lake, Bucharest. The specimen was accidentally deteriorated

after identification. The first mention for Romania was made by Negrea (1983), who

identified the species in a temporary pool from Ieşelniţa, in the Crapina-Jijila lake

complex, in the Împuţita fleet of the Danube Delta and in the Northern Bay of Sulina (the

mixing zone), so it was to be expected in the Tineretului Lake as well.

a) b)Fig. 4 - Camptocercus uncinatus, a) female with one embrio; b) postabdomen (Negrea,

1983, fig. 126-I) and the distal end of the postabdomen (idem, fig. 126-J).

B. Subfamily CHYDORINAE Dybowski & Grochowski, 1894 emend. Frey,

1967

1.2.4. Chydorus sphaericus (O. F. Müller, 1776) s. str. emend. Frey, 1980 (Figs.

5a-b)


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a) b)Fig. 5 - Chydorus sphaericus s. str., female collected in Tineretului Lake

in 20.04.2008.

a) habitus; b) postabdomen.

Chydorus sphaericus s. str. has a clear preference for the submerged vegetationand the bottom detritus of eutrophic waters, being the most frequent cladoceran speciesin Romania (Negrea, 1983). Frey (1980) considers that C. sphaericus s. lat. is a speciescomplex for now containing as valid species C. sphaericus s. str. and C. brevilabris) andhe states that it is certainly not a true cosmopolitan species (with an universalgeographical distribution).

In the Tineretului Lake, the species did not manifested a particular preference tothe vegetation, either macrophytic or algal and it was the dominant species during the 2years of study (October 2007 - October 2009), being present in all collected samplescontaining cladocerans, with densities comprised between 5 and 135 individuals/cubicmeter.

First mention for the inferior Danube River sector was in the Greaca Lake(Dumitriu, 1934, cited by Negrea, 1962, p. 457, 486). First mention for the RomanianPlain was at Brăneşti pond (Murgoci & Vasiliu 1943, cited by Negrea, 1962, p. 458,485).

1.2.5. Chydorus sphaericus (O. F. Müller, 1776) caelatus Schoedler 1862 (Fig. 6.

a)


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a) b)Fig. 6 - a) Chydorus sphaericus caelatus. Two decomposing specimens

collected in Tineretului Lake in 20.10.2007. The caracteristic excavations (foveae)

are distinguishable on the ventral part of the valve (arrow). b) Pleuroxus aduncus

aduncus. Female with two embrios, collected in Tineretului Lake in July 2008.

This subspecies’ status is uncertain, incertae sedis (Smirnov, 1996). The ecology

is similar to the Chydorus sphaericus s. str. species as it cohabits with the latter. The C.

s. caelatus is diferentiated from the Chydorus sphaericus s. str. by the presence of

obvious excavations (foveae) on the valve, disposed in a paralel pattern to the ventral rim

of the valve, as well as on the cephalic shield, in the eye and ocellum area.

In Tineretului Lake the specimens were found in a plankton sample of October

2007 and it is the first mention for the Romanian Plain. Until now it was known from the

Surduc reservoir (Banat), some temporary pools of Argineşti forest and a temporary pool

of Cornet-Olt (Oltenia), the lake Jijila (inferior Danube River flood plain) and the

Somovelu backwater (Danube Delta) as Chydorus cf. sphaericus, vide Negrea, 1983, p.

267.

1.2.6. Pleuroxus aduncus aduncus Jurine, 1820 (Fig. 6b)

Negrea (1983) considers it a macrophytophylic subspecies, its favourite biotope

being the dense patches of floating or emerged aquatic vegetation during its maximum

development including the vegetal detritus and algae covered bottom; other biotopes:

silty or sandy bottoms less than 3 m deep, epiphyted rocks in the river beds. Frequent in

the waters of the Danube flood plain and Danube Delta, especially in the vegetated

shallows, the dead meanders, slow running rivers, fish ponds. The species was also


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identified in temporary pools and frequent in the plain waters, in flood plains (shallows,

backwaters, swamps, ponds and pools); it is relatively frequent in the litoral area of the

great plain lakes covered with vegetation and in shore lakes, having a good tolerance of

the salt contents. An eurithermal - thermophylic species, it has an optimum development

at 17˚-23˚C. The pH tolerance according to Negrea (1983) is between 6.5 and 7.8 but it

was found at a pH of 8.1 in the Chiriţa Lake, department of Iaşi (Calistru et al., 2000). In

Tineretului Lake it was present at a pH value of 8.

The species is cosmopolitan; in Europe is present everywhere except Iceland, the

northern Sweden and generally in the tundra biome. Although in Romania is present only

up to an altitude of 440 m it is cited in sites at 1400 m in the Alps and 1800 m in the

Caucasians.

First mention for the inferior Danube River sector: Spandl, 1926, p. 571, has

identified it in samples from this sector but he does not mention the exact location.

Regarding the Romanian Plain first mention: Negrea (1983, p. 239) has identified it in

samples from the Corbii Ciungi spring complex, lake Snagov and lake Ciolpani, Ialomiţa

River at Slobozia and Ţăndărei and the Frăsinet ponds.

1.3. Family DAPHNIIDAE

1.3.1. Simocephalus exspinosus (Koch, 1841) (Fig. 7a)

a) b) c)

Fig. 7 - Simocephalus exspinosus. a). Parthenogenetic female (6 embrios) from a

temporary pool, the small island from the Tineretului Lake, collected in July 2008.

b). Simocephalus vetulus. Parthenogenetic female with 12 eggs collected in 20th of April

2008 in Tineretului Lake in a Miriophyllum spicatum patch: habitus;

c) idem, detail of the head with the characteristic form of the ocellum.


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Macrophytophylic species, cohabiting with S. vetulus. It favours shallow water

bodies, heavily vegetated, ponds, pools, either permanent or temporary, dead meanders

in the flooded plains up to 950 m (Lacu Roşu - Negrea, 1983); also present in limnocrene

springs and some wells, in eutrophic and oligotrophic Sphagnum swamps as well as in

the shallows of the great plain lakes and reservoirs. Generally present in small numbers,

from April to November.

A holarctic, ethiopian and neotropical species, it is cited at 1130 m of altitude in

the Tatra Mountains and at 1920 m altitude in the Caucasian Mountains (Negrea, 1983).

In Europe it was cited on the entire territory except the Pirinees and the tundra biome.

Although it is considered a eurithermal-thermophylic species, in the Tineretului

Lake this species was collected starting with the month of March (the 7th of March

2008), unlike S. vetulus, that appeared only in April. Negrea (1983) gives for this species

a pH tollerance between 6.1 and 8, but it was found in Tineretului Lake at a pH value of

8,4 (Actors Teraces, 20th of April 2008).

First mention for the inferior Danube River sector: at Giurgiu (Spandl, 1926, p.

560). First mention for Romanian Plain: as „Simocephalus exspinosus” in the Nucet

fishing ponds, Danube River basin (Vasiliu & Nicolau, 1947, cited by Negrea, 1962,

p. 427).

1.3.2. Simocephalus vetulus (O. F. Müller, 1776) (Figs. 7b-c)

Acording to Negrea (1983) it is a macrophytophylic species, eurithermal

thermophylic (11-28.5°C), very tolerant regarding the pH values (5 to 8.1). It is

considered as one of the most frequent species of Daphniids in Romania, excepting the

high altitudes (maximum altitude of 950 m, at Lacu Roşu).

Probably a cosmopolitan species, it is mostly encountered in the flood plains and

the Danube Delta (lakes, backwaters and temporary pools as well as the main stream); it

favour ponds, dead meanders, flooded plains and macrophytic vegetation invaded lakes

and eutrophic swamps. It is less frequent in springs and their collectors, in wells, periodic

pools and it was mentioned for the Danube sea-river water mixing zone.

In the Tineretului Lake the species is frequent in the temporary pools, maximum

15 cm deep, formed by the water level rising in the spring and summer period (May to

July) on the small island in the NW part of the lake, as well as in the rich submerged

macrophytic vegetation starting with the month of April (20.04.2008).


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It was first mentioned for the inferior Danube River sector area in the Greaca

Lake, (Spandl, 1926, p. 560). It was first mentioned in the Romanian Plain, in the

Danube River basin in the Nucet fishing ponds (Vasiliu & Nicolau, 1947, cited by

Negrea, 1962, p. 428).

1.4. Family ILYOCRYPTIDAE

1.4.1. Ilyocryptus agilis (Kurz, 1878) (Fig. 8)

The morphology of Ilyocryptus agilis species is an indication of its

favourite habitat, the muddy bottoms on which it moves with the help of antennae

and fornix. As it usual filters small detrital particles, the species is also present

in the epiphyton of the vegetation patches that are building silt deposits on

their leaves and stems and on plant bioderma (the typical biotope according to

Negrea, 1983). The species is less frequent in the water bodies from the Danube

River flood plain and delta, in rivers and small reservoirs from the Romanian Plain.

This species is considered rare in Sphagnum swamps in Poiana Stampei and the

mixing area of the Danube and Black Sea. Occasionally it is cited in temporary

plain pools.

The most often the species is perennial, with a peak of density in the months

of August and also September. From the temperature point of view the species

is stenothermal, with a large pH tolerance, from 3.6 to 7.9 according to Negrea

(1983).

In the Tineretului Lake it was found at a pH value of 8, in muddy and sandy

bottom samples from the end part of the lake, but was never found on vegetation

samples.

The species is palearctic, present in all the Europe with the exception

of the Pirenees Mountains, the Panonic Plain, the northern Carpathian Mountains, Island

and also the tundra region. In the Caucasian Mountains it was cited at an altitude of

2021 m.

The first mention for the Romanian Plain area for this taxon it was in a sample

from the Vedea River, in the Dâmbovnic River at Slobozia, and a temporary pool at

Roşu, near Bucharest (Negrea, 1983, p. 194).


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Fig. 8 - Ilyocryptus agilis. Decomposing specimen collected in the Tineretului Lake, in

07th of March 2008. Dorsal view, evidentiating the disparate proportion between

the head with the strong antennae and the rest of the body.

1.5. Family MACROTHRICIDAE

1.5.1. Macrothrix laticornis (Fischer, 1848) (Figs. 9a-b)

Smirnov (1976) considers the fact that as a first description acceptable of the

species, accompanied by figures, the one made by Fisher in 1848, under Daphnia

curvirostris, even if the name of laticornis was given later by Desmarest in 1825, as

Lynceus laticornis.


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This is the European species of the Macrothrix laticornis complex according

to Silva-Briano et al. (1999), possibly western palearctic (Smirnov, 1992), present

all over the Europe except Iceland and northern Sweden. The species is stenothermic,

found even under ice (according to Negrea, 1983). It is relatively frequent in all size

hill and plain rivers in Romania, including in the ponds and pools of their flood plains;

in the Danube River, including the stagnant water bodies of the Delta and the Danube

Plain. It is less frequent in reservoirs and rare in large plain lakes. The main biotope:

silty, shallow bottoms, devoided of macrophytic vegetation and rich in organic

substances of eutrophic, vegetated lakes. Other biotopes: sandy, rocky bottoms

with accumulations of organic detritus or epiphytal algae; emerged, submerged or

floating vegetation near the bottom.

In Romania is cited up to 1250 m altitude. Perennial species, relatively

frequent but always in small numbers, a density peak being reached in September

(Negrea, 1983).

a) b)Fig. 9 - Macrothrix laticornis, colected in the Tineretului Lake in 07.03.2008,

female with empty incubator chamber. a) general appearance; b)

detail of the postabdomen.


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In Tineretului Lake, only one specimen of the species was found so far, in atransect sample from March 2008.

First mention for the Romanian Plain: numerous samples from the rivers Vedea,Dâmbovnic, Neajlov, Argeş, the Podişor pond, a temporary pool from Pantelimon (nearBucharest) and Greaca Lake (for the inferior Danube River sector) (Negrea, 1983, p.208).

2. Order CTENOPODA2.1. Family SIDIDAE2.1.1. Sida crystallina crystallina (O. F. Müller, 1776) (Figs. 10a-b)Macrophytophilic subspecies, specific to stagnant waters from the Palearctic

region. Acording to Korovchinsky (1992) the areal includes Europe, Iceland, Siberia andMongolia and excepting the Iberic Peninsula and the far eastern part of Siberia.According to Negrea (1983), in Romania it is found up to 910 m of altitude (in PoianaStampei). Here it prefers the vegetated area of the plain eutrophic lakes; it reachesmaximum densities during the summer (June to July) in compact Potamogeton thicket; itprefers the deep, clear water bodies, with a good oxygen content, where it attaches itselfon plants with its nucal organ and filters small particles of nutrient. It is a thermophyliccladoceran with an optimum development at 16-26˚C; it survives at different pH values(ranging from 5 to 8.4) with a preference for neutral pH. It is an indicator species forclean waters.

In the Tineretului Lake, the species was present from April to May as well as in

October, in small numbers, in vegetation thickets.

a) b)Fig. 10 - Sida crystallina crystallina. a) the head with the nucal organ and the eye;

b) the postabdomen and the terminal claws.

First mention for the inferior Danube River sector: Greaca Lake (Dumitriu, 1934,

cited by Negrea, 1962, p. 413). First mention for the Romanian Plain: samples from

Cernica reservoir (near Bucharest), Ciolpani Lake and Snagov Lake and Ialomiţa River

at Micşuneştii Mari (Negrea, 1983, p. 77).


134

Conclusions

Twelve cladoceran species and subspecies have been identified, belonging to the

Ctenopoda order, Sida crystallina crystallina, and Anomopoda order: Bosmina

longirostris, Alona affinis, Alona costata, Camptocercus uncinatus, Chydorus sphaericus

s. str., Chydorus sphaericus caelatus, Pleuroxus aduncus aduncus, Simocephalus

exspinosus, Simocephalus vetulus, Ilyocryptus agilis and Macrothrix laticornis.

Looking into the ecological significance of the identified cladoceran species, we

can assess that the presence of relatively important densities of the Sida crystallina,

Chydorus sphaericus (oxyphylic species) as well as the presence of the species

Pleuroxus aduncus, Alona affinis, Alona costata and Simocephalus vetulus are indicating

a good or a very good water quality for the Tineretului Lake during the months of

October 2007 - May 2008, which is also corroborated with the physical and chemical

parameter analysis of the lake water during the same period (e.g. dissolved oxygen

content over 7 mg/l). The situation was repeated in the winter and spring of 2009. The

saprobity indicators were not analyzed due to the lack of financial means.

Instead, the euplanktonic species of daphniids from the Daphnia and

Ceriodaphnia genera are missing entirely from this lake.

Dumont & Negrea (2002) are indicating an average of 50 cladoceran species for

an average size eutrophic lake of the plain region in the Holarctic region, which signifies,

at a present rate, that the Tineretului Lake has a low cladoceran diversity.

The comparison with the available data provided by other authors on Romanian

lakes of the same or larger size as those sampled in the area of Iaşi by Calistru et al.

(2000) have a smaller average of species, going from 1 to 15 species which indicates a

high species richness factor for the Tineretului Lake, despite its position in the center of

Bucharest. Some of the species and subspecies were never indicated previously in this

area: Camptocercus uncinatus, Alona costata and Chydorus sphaericus caelatus.

Acknowledgements

The authors would like to thank Mrs. Marinela Năzăreanu for the China ink

copies of the contours in Figs. 2-10.


135

References

ANTONIU MURGOCI A., VASILIU G. D., 1943, Vergleichende anatomisch-physiologische Untersuchungen bei einem Fall von Kopfmissbildung beiCarassius auratus Bloch. An. Inst. Cerc. Pisc. Rom., 2, vol. 2, 141-151.

BUŞNIŢĂ T., LUCA V., 1938, Variaţiile sezonale ale planctonului în eleştee. Bul. Soc.Nat. România, 12, 11-17.

CALISTRU M., NEGREA Ş., MUSTAŢĂ G., 2000, The structure and dynamics of someCladocera living in Ciric and Chiriţa Lakes, Analele Ştiinţifice ale Universităţii“Al. I. Cuza” Iaşi, s. Biologie animală, XLVI, 52-62.

DUMITRIU M., 1934, Lacul Greaca. Contribuţie la o monografie hidrobiologică cuaplicaţie la pescărie. An. Instit. Cerc. Agr. Rom., 5, vol. 6, 419-448.

DUMONT H. J., NEGREA Ş., 2002, Brachiopoda in: Guides to the Identification ofMicroinvertebrates of the Continental Waters of the World, vol. 19, Leiden,Belgium, 398.

FREY D. G., 1980, On the plurality of Chydorus sphaericus (O. F. Muller) and thedesignation of a neotype from Sjaelsø, Denmark, Hydrobiologia, 69, 1-2, 83-123.

HURDUGAN-IRIMIA O., 2008, Influenţa macrofitelor acvatice (Potamogeton crispus,Myriophyllum spicatum) asupra factorilor fizico- chimici din Lacul Tineretului,Bucureşti, Oltenia. Studii şi comunicări. Ştiinţele Naturii, XXIV, 237-242.

JEPPESEN E. T., LAURIDSEN T., KAIRESALO T., PERROW M. R., 1998, Impact ofmacrophytes on fish-zooplankton interactions in lakes. In: The structuring role ofsubmerged macrophytes in Lakes. JEPPESEN E., SØNDERGAARD M.,CHRISTOFFERSEN K., (eds.), Springer, New York, 91-114.

KOROVCHINSKY N. M., 1979, On intraspecific taxonomy of Sida crystallina(Crustacea, Cladocera) of Holarctics, Zool. Jurn., 58, 12, 1777-1789.

KOROVCHINSKY N. M., 1992, Sididae and Holopediidae (Crustacea: Daphniiformes)in: Guides to the Identification of the Microinvertebrates of the ContinentalWaters of the World, 3 Leiden, Belgium, 86.

MOTAŞ C., BOTOŞĂNEANU, L., NEGREA Ş., 1962, Cercetări asupra biologieiizvoarelor şi apelor freatice din partea centrală a Câmpiei Române, Ed. Acad. R.P. R, Bucureşti, 366.

NEGREA Ş., 1959, Contribution à l’étude des Cladocères des eaux roumaines de la MerNoire. Lucrările sesiunii ştiinţifice (15-17 septembrie 1956) a Staţiunii zoologicemarine “Prof. Ioan Borcea» Agigea, Univ. «Al. I. Cuza», Iaşi, 223-256.

NEGREA Ş., 1962, Conspectul faunistic şi chorologic al Cladocerilor (Crustacea,Cladocera) din R. P. România, Probleme de biologie, Ed. Academiei, Bucureşti,403-511.

NEGREA Ş., 1966, Contribuţii critice la cunoaşterea cladocerilor (Crustacea) dinTransilvania existenţi în colecţia lui E. Daday (1884) din Cluj, St. Cercet. Biol.Zool. Bucureşti, 305-313.


136

NEGREA Ş., 1974-1975, Clef dichotomique pour les principales espèces de Cladocères(Crustacea, Cladocera) de Roumanie. Travaux de la Station «Stejarul»,Limnologie, 11-37.

NEGREA Ş., 1983, Cladocera. Fauna Republicii Socialiste România, Editura AcademieiRomâne, Bucureşti, 4: 12, 399.

NEGREA Ş., 2007, Cladocera, (Crustacea: Branchiopoda). In: Lista faunistică aRomâniei (specii terestre şi de apă dulce), MOLDOVAN, O. T. et al. (eds.), Cluj-Napoca, 84-85.

NEGREA Ş., 2004, Mic dicţionar de termeni pentru mediile subterane terestre şiacvatice şi fauna lor. In: NEGREA Ş., NEGREA A., ARDELEAN A. –Biodiversitatea în mediile subterane din România, Arad, 217-244.

NEGREA Ş., NEGREA A, 1975, Ecologia populaţiilor de cladoceri şi gasteropode dinzona inundabilă a Dunării, Ed. Academiei Republicii Socialiste România,Bucureşti, 232.

NEGREA Ş., Pîrvu C., 1977, Studiul cladocerilor din mlaştinile Stegardin, Bîlbîitoarea şiFăget, Hidrobiologia, Bucureşti, 15, 193-204.

NEGREA Ş., PÎRVU C., 1980, Contribuţii la ecologia cladocerilor din mlaştinile Manta,Benii V şi lacul Vitioara, Hidrobiologia, Bucureşti, 16, 167-173.

SILVA-BRIANO M., DIEU N. Q., DUMONT H. J., 1999, Redescription of Macrothrixlaticornis (Jurine, 1820) and description of two new species of the M. laticornis-group. Hydrobiologia, 403, 39-61.

SMIRNOV N. N., 1976, Macrothricidae I Moinidae faunî Mira. Fauna SSSR, 1, 3 (n. s.112), 237.

SMIRNOV N. N., 1992, Guides to identification of the microinvertebrates of continentalwaters of the world. 1. The Macro-thricidae of the world. The Hague, SPBAcademic Publishing, 143.

SMIRNOV N. N., 1996, Cladocera: Chydorinae and Sayciinae (Chydoridae) of theWorld, Guides to the Identification of the Microinvertebrates of the ContinentalWaters of the World vol. 11, SPP Academic Publishing, Amsterdam, Netherlands,198.

SPANDL H, 1926, Wissenschaftlische Forschungs ergebnisse aus dem Gebiete derunteren Donau und des Schwarzen Meeres, II Die Süsswasser-Mikrofauna. Arch.f. Hydrobiol., 16, 528-603.

VAN DAMME K., DUMONT H. J., 2008, The ‘true’ genus Alona Baird, 1843(Crustacea: Cladocera: Anomopoda): position of the A. quadrangularis - groupand description of a new species from the Democratic Republic of Congo,Zootaxa, 1–25.

VAN DAMME K., KOTOV A. A., DUMONT H. J., 2010, Names checklist in AlonaBaird 1843 (Crustacea: Cladocera: Chydoridae) and their current status: ananalysis of the taxonomy of a lump genus, Zootaxa 2330, 1-63.


137

VASILIU G. D., Nicolau A., 1947, Contributions à la connaissance de la variation

qualitative et quantitative du plancton des bassins de Nucet au cours de l’année

1944. An. Inst. Cerc. Pisc. Rom., (3-6), 3, 5-35.


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Authors1 Ştefan NEGREA

[email protected] Institute “Emil Racoviţă”,

13 Septembrie Street 13, Bucharest, Romania, RO-050711.2 Oriana IRIMIA-HURDUGAN

[email protected]“Alexandru Ioan Cuza” University, Faculty of Biology,

Bd. Carol I, nr. 20A, Iaşi, Romania, RO-700505.

mailto:[email protected]

mailto:[email protected]

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