ABUNDANCE AND PRODUCTION OF BRANCHIURA SOWERBYI (OLIGOCHAETA: TUBIFICIDAE) IN TWO TYPICAL SHALLOW LAKES (HUBEI, CHINA)

ＩＮＴＲＯＤＵＣＴＩＯＮＢｒａｎｃｈｉｕｒａｓｏｗｅｒｂｙｉ,ａｃｏｓｍｏｐｏｌｉｔａｎｔｕｂｉｆｉｃｉｄ,ｉｓａｐｒｅｄｏｍｉｎａｎｔｚｏｏｂｅｎｔｈｏｓｉｎｍａｎｙｓｈａｌｌｏｗｌａｋｅｓｉｎＣｈｉｎａ(Ｌｉａｎｇ,1979).Ｉｎ1984,ｔｈｅｐｒｏｄｕｃｔｉｏｎｒａｔｅｓｏｆｔｈｅｓｐｅｃｉｅｓｗｅｒｅｆｉｒｓｔｅｓｔｉｍａｔｅｄｉｎＤｏｎｇｈｕＬａｋｅ,Ｗｕｈａｎ(Ｌｉａｎｇ,1984).Ａｆｔｅｒｔｈａｔ,ｎｏｄａｔａｏｎｐｒｏｄｕｃｔｉｏｎｏｆｔｈｉｓｗｏｒｍｏｒｏｔｈｅｒｚｏｏｂｅｎｔｈｏｓｗｅｒｅｐ…     

Annual production ofBranchiura sowerbyi (Oligochaeta: Tubificidae) in the Donghu Lake,Wuhan, China

Branchiura sowerbyi in the Donghu Lake (Wuhan, China) completes its life cycle in one year. Its production rates were 6.7 g m⁻² yr⁻¹ (wet weight) during the period from April 1962 to May 1963 and 8.6g m⁻² yr⁻¹ during the period from August 1963 to August 1964. The standing stocks in corresponding periods were 1.9g m⁻² (wet weight) and 1.1g m⁻², and theP/B ratios were 3.6 and 7.8. Based on the standing stock during 1973–1975, an evaluation of recent productin levels ofB. sowerbyi in Donghu Lake has also been made (i.e. 5.7–33.5g m⁻² yr⁻¹).     

Energy flow in Branchiura sowerbyi (Oligochaeta: tubificidae) in a shallow macrophyte-dominated lake, Biandantang Lake

The energy flow ofBranchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (12.5241kJ/m²a), egestion (517.7302kJ/m²a), metabolism (38.3273 kJ/m²a), and excretion (4.3798kJ/m²a). The net growth efficiency of the species is about 22.7%, which accords well with the generally reported value for oligochaetes. In addition, the relationship between starvation respiration (R, mgO₂/ind·d), wet weight (Ww, mg) and temperature (T, °C) were also measured, with the regression function beingR=0.008Ww^0.736 e^0.050T. Project supported by NSFC (30270278, 3960019), the foundation of the government of Hubei Province (No. 2000J109), and the foundation of Ecological Station, CAS in the Institute of Hydrobiology.     

ABUNDANCE AND PRODUCTION OF LIMNODRILUS HOFFMEISTERI （OLIGOCHAETA ： TUBIFICIDAE） IN ALGAE-DOMINATED LAKE HOUHU （WUHAN, CHINA）

April, 1996 to March, 1997 studies on the abundance and secondary production of Limnodrilus hoffmeisteri in an algae-dominated lake showed that the worm density and biomass peaked in December at 152 ind/m^2 and 0.087 g/m^2 , respectively. The secondary production of the animal was 0.294g/m^2 fresh wt/a. The turnover rate (P/B ratio) was 11.4.     

Energy flow in Branchiura sowerbyi （Oligochaeta： tubificidae） in a shallow macrophyte-dominated lake, Biandantang Lake

The energy flow of Branchiura sowerbyi was studied for the first time in China in a shallow macrophytic lake, Biandantang Lake, Hubei Province. The energy flow was calculated from the measurement of flesh production (12.5241kJ/m^2a), egestion (517.7302kJ/m^2a), metabolism (38.3273 kJ/m^2a), and excretion (4.3798kJ/m^2a). The net growth efficiency of the species is about 22.7%, which accords well with the generally reported value for oligochaetes. In addition, the relationship between starvation respiration (R, mgO2/ind‘d), wet weight (Ww, mg) and temperature (T, ℃) were also measured, with the regression function being R=0.008 Ww^0.736 e^0.050T.     

Response of rotifer community to environmental changes in five shallow lakes in the middle reach of Changjiang River,China

We evaluated the response of a rotifer community to environmental changes in five shallow lakes in the middle reach of the Changjiang （Yangtze） River in summer and autumn 2010. These five lakes differed in trophic status and rotifer community structure. Twenty-nine rotifer species were collected, of which Keratella cochlearis, Polyarthra dolichoptera, and Trichocerca elongate were dominant. The mean density, Shannon-Wiener diversity, and equitability among the five lakes differed significantly （P〈0.05）. The mean rotifer density was positively correlated with trophic state. The diversity was higher in lakes with high macrophyte coverage. The composition of rotifer species was closely associated with the trophic gradient. Five environmental variables, Secchi depth, conductivity, TN, NHa-N, and TP, significantly affected the composition of rotifer species. Keratella quadrata, Brachionus calyciflorus, and B. forficula were more common in eutrophic conditions. Our results suggest that eutrophication has a significant influence on the rotifer community structure and highlight the potential for using rotifer community structure as an indicator of trophic status in subtropical lakes.     

Life cycle and production of chironomidae (diptera) in Biandantang, a typical macrophytic lake (Hubei, China)

ＩＮＴＲＯＤＵＣＴＩＯＮＡｌｔｈｏｕｇｈｄｅｓｃｒｉｐｔｉｏｎｏｆｌｉｆｅｈｉｓｔｏｒｙａｎｄｅｓｔｉｍａｔｅｓｏｆａｎｉｍａｌｐｒｏｄｕｃｔｉｏｎｈａｖｅａｌｏｎｇｈｉｓｔｏｒｙ (Ｌｉｎ ｄｅｇａａｒｄ ,1 989) ,ｆｅｗｓｔｕｄｉｅｓｏｎｔｈｅｐｒｏｄｕｃｔｉｏｎｒａｔｅｏｆｂｅｎｔｈｉｃｍａｃｒｏｉｎｖｅｒｔｅｂｒａｔｅｓｗｅｒｅｃａｒｒｉｅｄｏｕｔｉｎＣｈｉｎｅｓｅｗａｔｅｒｓ (Ｌｉａｎｇ ,1 984 ) .Ｗｉｔｈｔｈｅｄｅｖｅｌｏｐｍｅｎｔｏｆｆｉｓｈｅｒｉｅｓａｎｄｔｈｅｄｅｔｅｒｉｏｒａｔｉｏ…     

ENERGY FLOW OF BELIAMYA AERUGINOSA IN A SHALLOW ALGAL LAKE, HOUHU LAKE （WUHAN, CHINA）

The energy budget ofBellamya earuginosa in a shallow algal lake, Houhu Lake (Wuhan, China) was investigated by the measurement of flesh production (32.8 kJ/(m²·a)), egestion (337.7 kJ/(m²·a)), metabolism (246.7 kJ/(m²·a)), and estimation of excretion (21.4kJ/(m²·a)). The net growth efficiency of the species is about 10.9%, which accords with the generally reported value for gastropods. In addition, the relationships between starvation respiration (R, mgO₂/(Ind·d)), body weight (Wd, mg in dry wt) and temperature (T, °C) were also determined. The regression equationR=0.044Wd ^0.537 e ^0.061T was obtained by the least square method, The measured SDA of the species is 26.51% of its gross metabolism. Project No. 3960019 and 39430101 supported by NSFC and also a granted for the East Lake Ecological Experimental Station, CAS, Wuhan.     

Seasonal fluctuation of Myxobolus gibelioi（Myxosporea） plasmodia in the gills of the farmed allogyno—genetic gibel carp in China

The seasonal fluctuation of the plasmodia ofMyxobolus gibelioi Wu et Wang, 1982 in the gill filaments of the allogynogenetic gibel carpCarassius auratus gibelio (Bloch) in a fish pond in Hubei Province of China was investigated from August 1999 to July 2000. A total of 445 fish was examined; the overall prevalence of the plasmodium infection in the fish was 64.94% and mean abundance of plasmodia was 11.65±27.85 (mean±SD). Significant seasonal changes in prevalence and mean abundance, with higher levels of the plasmodia infection from late spring to autumn, were observed. This research was financially supported by the Projects for Knowledge Innovation of the Chinese Academy of Sciences (No. KSCX2-1-04 and No. 1999051) and the Science & Technology Commision of Wuhan City (No. 995004095G).     

Life history, secondary production and trophic basis of two dominant mayflies in a subtropical stream of China

Mayflies constitute a major part of macroinvertebrate biomass and production in Iotic ecosystems, and play an important role in material cycle and energy flow. There are more than 250 species of mayflies in rivers and streams of China. In order to learn their ecological functions, an investigation on life cycle, production and trophic basis of dominant species of mayflies in a second-order branch of Hanjiang River basin, Hubei, China was carried out during June 2003 to June 2004. The results showed that the dominant mayfly species Epeorus sp. and Caenis sp. developed two generations per year; in term of Epeorus sp., pupation mainly occurred in spring and then from late summer to early autumn, while Caenis sp. pupated in spring and autumn. The abundance and biomass of the Epeorus sp. population peaked twice （1 226 ind/m^2, 3.142 5g/m^2） in April and June. Caenis sp. also had two peaks （307ind/m^2, 1.590 g/m^2）, but in February and June. Cohort production and cohort P/B ratio of Epeorus sp. were 161.009 g/m2 wet weight and 7.7, respectively, and annual production and P/B ratio were 267.46g/m^2.a wet weight and 15.4, respectively; cohort production and P/B ratio of Caenis sp. were 26.7995g/m^2 wet weight and 4.7, its annual production and P/B ratio were 53.60 g/m2.a wet weight and 9.4, respectively. For Epeorus sp., the proportions contributing to secondary production of the main food types were： amorphous detritus, 33.46%; fungi, 10.83%; vascular plant detritus, 1.80%; diatoms, 53.90%; for Caenis sp., the proportions were 70.79%, 6.90%, 3.52% and 18.77%, respectively.     

REPORT ON PONTONIINE SHRIMPS（CRUSTACEA：DECAPODA）COLLECTED BY JOINT CHINESE—GERMAN MARINE BIOLOGY EXPEDITIONS TO HAINAN ISLAND,SOUTH CHINA SEA i.ANCHISTUS,CONCHODYTES,CORALLIOCARIS

The present paper reports 7 species of pontoniine shrimps collected from Hainan Island,South China Sea,by the Joint Chinese-German Marine Biology Expeditions,in which,Conchodytes nipponensis(De Haan,1844)and Coralliocaris brevirostris Borradaile,1898 are new records from Chinese waters.     

Effects of salinity, light and temperature on growth rates of two species of Gracilaria （Rhodophyta）

Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G. tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32°C, 30 and 240 μmol/(m²·s) for G. lichenoides, and 24°C, 20 and 200 μmol/(m²·s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30°C, 32.10, and 287.23 μmol/(m²·s) for G. lichenoides (16.26%/d), and 25.38°C, 21.10, and 229.07 μmol/(m²·s) for G. tenuistipitata (14.83%/d), respectively. Supported by the 908 Special Program (908-02-04-07), the National Basic Research Program of China (973 Program, No. 2006CB400608), and K. C. Wong Magna Fund in Ningbo University     

Three new species of Batrachospermum Roth （Batrachospermaceae, Rhodophyta） in China

Three new species of Batrachospermum Roth (Batrachospermales, Rhodophyta) from China are described in this paper. B. yunnanense sp. nov. has long-cylindrical trichogynes with long stalks and is diagnostic of section Virescentia. Within this section, B. yunnanense is similar to B. helminthosum Bory emend. Sheath et al., but it is dioecious and has curved carpogonial branches, while the latter is monoecious and has straight carpogonial branches. It is also similar to B. transtaganum Reis, but it differs from the latter in long carpogonia,big carposporophytes and carposporangia. It is considered that B. nothocladoideum sp. nov. is assigned to section Contorta, subsection Kushiroense, because its carpogonial branches are twisted and gonimoblast filaments are loosely agglomerated. This new species similar to B. iriomotense Kumano, but with short fascicles, long-ovoid or subpyriform cells, numerous terminal hairs, long-ellipsoid trichogynes, big carposporophytes and small carposporangia. The plant is quite tough and cartilaginous and similar to Nothocladus in gross morphology, but its carposporophytes are compact instead of diffuse. This shows that it may be a transitional species between section Contorta and genus Nothocladus. So, B. transitorium sp. nov. should belong to section Contorta, subsection Kushiroense, because of its curved or twisted carpogonial branches and loosely agglomerated gonimoblast filaments, with globose or subglobose cells in fascicles similar to B. spermatiophorum Vis et Sheath, but no colourless spermatiophores. In terms of small and numerous carposporophytes, B. transitorium sp. nov. is similar to some species of section Batrachospermum. However, their other features are unique, indicating its transitional nature between section Contorta and Batrachospermum.     

Two new species of the genusDorylaimopsis Ditlevsen, 1918 (Nematoda: Adenophora,Comesomatidae) from the Bohai Sea,China

Two nematode species of the genusDorylaimopsis (Family Comesometidae) from the Bohai Sea are described.Dorylaimopsis rabalaisi n. sp. similar toD. punctata Ditlevsen, 1918 from which it can be separated by the small size, short and simple spicules without ventral apophyses or joint line.Dorylaimopsis turneri n. sp. differs from the closest speciesDorylaimopsis angelae (Inglis, 1967) by its higher values of de Man ratio ‘a’, much shorter spicules and higher ratio of gubernacular to spicules length. A key to species of the genus based on the key by Jensen (1979) is given. This project was supported by the National Science Foundation, No: 3860804     

Hypoglossum fujianensis sp. nov. (Delesseriaceae, Rhodophyta) from Fujian Coast, China

Hypoglossum fujianensis sp. nov. is an epiphytic alga in the intertidal zone. Plants are light red, 0.9–2 cm high. Margin of branches gives rise to uniseriate hair-like rhizoids, formed outward from the fusion of the second-and third-order cells. Blades are single layered (except the midrib) and uncorticated. Tetrasporangial sori are formed on the middle part of blades. The globular tetrasporangia are developed from lateral pericentral cells. Project 39391800 supported by the NSFC.     

Notes on Two Marine Ciliates from the Yellow Sea,China： Placus salinus and Strombidium apolatum（Protozoa, Ciliophora）

The living morphology and infraciliature of two rare marine ciliates, Placus salinus Dietz, 1964 and Strombidium apolatum Wilbert and Song, 2005, collected from the coastal waters near Qingdao, China, were investigated by in vivo observation and protargol impregnation technique. The improved diagnosis for Placus salinus is as follows: medium-sized marine Placus, in vivo (50–60)μm×(30–40)μm; cell elliptical to barrel-shaped; 28–31 somatic kineties; single macronucleus usually ellipsoid and one micronucleus located in the indention of the macronucleus; one contractile vacuole posteriorly positioned. Strombidium apolatum is characterized by: marine strombidium (40–60)μm×(30–45)μmm in vivo, cordiform in shape with somewhat pointed posterior end and conspicuous apical protrusion; extrusomes prominent, about 15μm in length and evenly arranged along the circle kinety; about 16 collar and 5–6 buccal membranelles; one elongate macronucleus and one micronucleus; circle and ventral kineties consisting of about 53 and 45 dikinetids respectively.     

Preliminary studies onIndomysis annandalei (Mysidacea,crustacea) from Karachi waters with a brief account of its larval development

Population, seasonal abundance of the mysidIndomysis annandalei Tattersal (1914) from Karachi waters (northern Arabian Sea) are studied. Occurrence of breeding females is noted and developmental stages are described.     

Proteocephalus sinocyclocheili n. sp. (Cestoda: Proteocephalidae) in a fishSinocyclocheilus grahami tingi Fang from Yunnan, China

A new species ofProteocephalus from the fishSinocyclocheilus grahami tingi, a subspecies endemic to Fuxian Lake in Southwest China,is described. This is the first report of cestode from this host. The new species differs fromP. exiguus, P. Longicollis, P. parasiluri andP. torulosus, the only other species ofProteocephalus currently reported from China, by lacking an apical sucker, fromP. exiguus by having 45–108 rather than 24–54 testes per proglottis, and a maximum of 15 rather than 28 uterine diverticula; fromP.longicollis by having an average of 45–108 rather than 75–115 testes per proglottis and testes being in a single layer instead of 2 layers; and fromP. torulosus by having 45–108 instead of 150 testes per proglottis and testes being in 3–4 layers; and fromP. parasiluri by having 45–108 rather than 180 testes per proglottis. It resemblesP. percae, P. pollanicola, andP. thymalli in number of testes and uterine diverticula, but differs by lacking an apical sucker.Proteocephalus thymalli, like the new species, has a vagina that opens dorsally to the cirrus sac, butP. thymalli slao has postovarian testes, which the new species lacks. The possible significance of parasitological examinations of the other two subspecies ofS. grahami in two lakes close to Fuxian Lake is discussed in relation to host speciation and coevolution of the host-parasite system.     

Preliminary identification of three new isolates in genus Alexandrium (Dinophyceae) from China sea area

The 5.8S ribosomal DNA sequences (5.8S rDNA) and their flanking regions, internal transcribed spacer 1 and spacer 2 (ITS1 and ITS2) of three new isolates in genus Alexandrium (Alexandrium sp. qd1, Alexandrium sp. qd2, Alexandrium sp. gz) from China were amplified, sequenced, and subjected to phylogenetic analysis. Alexandrium sp. gz and Alexandrium sp. qd1 were grouped with high bootstrap values with four strains/species, i.e., A. catenella South Korea strain, A. catenella Japan strain, and two from China, Alexandrium sp. AC03 and Alexandrium sp. AN01 being proposed to be A. catenalla in a previous study. Then Alexandrium sp. gz and Alexandrium sp. qd1 were identified as Alexandrium catenella. As A. catenella was isolated from Qingdao and Guangzhou sea areas, it supposedly distributed at least in these two areas and was genetically different. Alexandrium sp. qd2 differed greatly from species in Alexandrium. It clustered with Symbiodinium californium, Symbiodinium sp. G15 and Gymnodinium sp. Zhao 01 with 100% bootstrap value; so Alexandrium sp. qd2 affiliates to genus Symbiodinium, and is probably a free-living Symbiodinium species.     

A new combination and two varieties of polystigmate Gomphonema (gomphonemaceae bacillariophyta) from Heilongjiang Province, China

The authors discribed a new polystigmate combination,Gomphonema turris Ehr. var.okamurae (Skv.) Fan et Bao. comb. nov., and two new varieties,Gomphonema turris Ehr. var.latum Fan et Wang. var. nov. andGomphonema acuminatum var.obtusum Fan et Bao, var. nov., that were distinguished by frustule morphology under LM. The samples were collected from freshwater of Heilongjiang Province, China. Project No. 39899400 supported by the NSFC.