The late Pleistocene/Holocene and recent Bosmina (Eubosmina) fauna (Crustacea: Cladocera) of the pre-alpine Starnberger See (FRG)

An analysis of the remains of Bosmina (Eubosmina) in a sedimentcore from the pre-alpine, mesotrophic Starnberger See showedthat the lake was inhabited by B. longispina since the OldestDryas. In the Subatlantic- -1900 years ago — the kesslerimorph of B. coregoni invaded the lake and both taxa have sinceco-existed. Although there was considerable morphological variation,B. longispina clearly differed from Circumbaltic populationsthrough most of the late Pleistocene and Holocene periods. Inthe recent Bosmina fauna of the lake two morphologically wellseparated taxa (B. longispina ruehei and a morph of B. coregoni)occur which differ clearly from the Bosmina remains found inthe core up to the uppermost sample from 7 cm sediment depth.B. coregoni f. kessleri appeared in the lake in a period whenit was supposedly still oligotrophic. The Bosmina successionobserved in the Starnberger See resembles the pattern foundin deep north German lakes.     

LEARNING AS A FACTOR IN DIET SELECTION BY ELYSIA VIRIDIS (MONTAGU) (OPISTHOBRANCHIA).

Elysia viridis (Montagu) occurs naturally in populations feedingon the fleshy, siphonalean green alga Codium or on the coarse,filamentous green alga Chaetomorpha. Only about half of theE. viridis transferred from Codium to Chaetomorpha in the laboratorywere able to learn to feed on this alga. Handling time decreasedsignificantly during the learning-period. All E. viridis transferredfrom Chaetomorpha to Codium in the laboratory were able to learnto feed on the latter alga. Handling time also decreased withexperience in these animals. Ingestive conditioning occurredin animals transferred from Chaetomorpha to Codium. These animalshad to go through a learning-period again when they were offeredChaetomorpha after 6–9 weeks with Codium Ingestive conditioningwas also evident from preference experiments; animals preferredthe food they had been kept on prior to the experiments. Thesefindings are discussed in relation to optimal diet theory. (Received 14 December 1987; accepted 22 March 1988)     

EASTERN MEDITERRANEAN OPISTHOBRANCHIA: DOTIDAE (DENDRONOTOIDEA), ARMINIDAE AND MADRELLIDAE (ARMINOIDEA)

An account is given of Doto, Armina and Madrella species collectedon diving and dredging expeditions to the Ligurian, Tyrrhenian,Adriatic, Ionian and Aegean Seas during the period 1973–1988,supplemented by material collected around Naples (southern Italy)and Banyuls (French Côte Vermeille). In all, 5 speciesof Doto, 3 of Armina and 1 of Madrella were investigated, yielding5 new records for the eastern Mediterranean Sea and one speciesnew to science, Armina tricuspidata from the Tyrrhenian Sea.The common arminid on the American coast from North Carolinato Texas is not A. tigrina as claimed by Abbott(1954) and byEyster (1981), but is a new species, for which we propose thename Armina abbotti. Consideration of world-wide records of Madrella leads to theconclusion that the senior Madrella sanguinea Angas, 1864, embracesM. ferruginosa Alder & Hancock, 1864, M. aurantiace Vayssière,1903 and M. granularis Baba, 1949 (but not the Japanese M. gloriosaBaba, 1949, which is probably distinct). ^*T.E. Thompson died in a car accident 1 January 1990. (Received 2 May 1989; accepted 4 November 1989)     

大和切叶蜂对其蜜源植物披针叶黄华的盗蜜行为

【目的】调查和观测内蒙古毛乌素沙地大和切叶蜂Megachile (Xanthosaurus) japonica Alfken对其蜜源植物披针叶黄华Thermopsis lupinoides (L.)的盗蜜行为。【方法】在披针叶黄华花期内, 设置样方观测披针叶黄华的主要访花昆虫。采用目测, 拍照等方法对大和切叶蜂盗蜜行为进行观测, 记录和统计花被盗蜜后留下的盗蜜孔的数量和在花上的位置。【结果】大和切叶蜂在披针叶黄华传粉蜂中数量上占有绝对的优势。作为初级盗蜜者时, 用上颚在花基部切割出一个纵向裂口, 将口器伸入孔内吸取花蜜。作为次级盗蜜者时, 利用已有的孔洞来吸蜜。在盗蜜时没有表现出寻找已经存在的盗蜜孔来吸蜜的现象, 同时其个体在盗蜜时表现出“偏好”花基部一侧的行为。在13个样地, 已开放花朵被盗蜜率最低为95.4%, 最高达到100%, 而未开放花朵的被盗蜜率最高则达到64.7%。【结论】在毛乌素沙地大和切叶蜂既是披针叶黄华的主要传粉者, 也是其初级盗蜜者和次级盗蜜者。     

Pollination Ecology ofChloranthus serratus(Thunb.) Roem. et Schult. andCh. fortunei(A. Gray) Solms-Laub. (Chloranthaceae)

Flowering and pollination biology ofChloranthus serratusandChloranthusfortuneiwere studied. Flowering took place from early Marchto mid–April inCh. fortunei, and from April to September,the whole growth period, inCh. serratus.The flowering periodof an inflorescence ofCh. serratusaveraged about 8 d and anthesisof a single flower was 5–6 d. Flowers are slightly protogynous.The flower emitted fragrance when the androecium became white.Both species are entomophilous with thrips as exclusive pollinators.Under natural conditions, fruit set occurs mainly as a resultof cross-pollination, but self-pollination and agamospermy mayoccur in some cases. In flowers ofCh. fortuneiandCh. serratus,theincurved androecium, the carpel and the spike axis form a nearlyclosed chamber that contains the anthers and stigma. The developmentof a floral-axial chamber may be an important step towards amore economical and effective pollination system. Floral morphology,pollination biology and fossil evidence suggest that the mainevolutionary trend in the genusChloranthusis towards developmentof ‘closed’ flowers. The fidelity of the relationshipbetweenChloranthusand thrips is regarded as a specialized featureof pollination biology and this relationship may have originatedearly in the evolutionary lineage.Copyright 1999 Annals of BotanyCompany Chloranthaceae,Chloranthus, Thysanoptera,flowering, floral-axial chamber, pollination, evolution trends.     

Feeding selectivities and food niche separation of Acartia clausi, Penilia avirostris (Crustacea) and Doliolum denticulatum (Thaliacea) in Blanes Bay (Catalan Sea, NW Mediterranean)

Selectivity-size spectra, clearance and ingestion rates andassimilation efficiencies of Acartia clausi (Copepoda), Peniliaavirostris (Cladocera) and Doliolum denticulatum (Doliolida)from Blanes Bay (Catalan Sea, NW Mediterranean) were evaluatedin grazing experiments over a wide range of food concentrations(0.02–8.8 mm³ L^–1 plankton assemblages from BlanesBay, grown in mesocosms at different nutrient levels). Acartiaclausi reached the highest grazing coefficients for large algae>70 µm (longest linear extension), P. avirostris forintermediate food sizes between 15 and 70 µm, and D. denticulatumfor small sizes from 2.5 to 15 µm. Penilia avirostrisand D. denticulatum acted as passive filter-feeders. Acartiaclausi gave some evidence for a supplementary raptorial feedingmode. Effective food concentration (EFC) decreased linearlywith increasing nutrient enrichment for D. denticulatum andfollowed domed curves for A. clausi and for P. avirostris withmaximum values at intermediate and high enrichment levels, respectively.Clearance rates of crustacean species showed curvilinear responseswith narrow modal ranges to increasing food concentration. Clearancerates of D. denticulatum increased abruptly and levelled intoa plateau at low food concentrations. Mean clearance rates were13.9, 25.5 and 64.1 mL ind.^–1 day^–1, respectively.No clearance could be detected for A. clausi at food concentrations<0.1 mm³ L^–1 and for P. avirostris at food concentrations     

THE DISTRIBUTION OF SOME ANTARCTIC NUDIBRANCHS (OPISTHOBRANCHIA)

The circumpolar distribution of the four revised species ofdoridacean nudibranchs: Aegires albus, Bathydoris hodgsoni,B. clavigera and Austrodoris kerguelenensis, is demonstrated,taking into consideration the known data from the literatureand new localities from the Atlantic sector of the Antarctic.A. albus and B. hodgsoni are restricted to the High AntarcticZone. A. kerguelenensis is widely distributed in the High Antarcticand Subantarctic Zone, whereas localities of B. clavigera arerestricted to the High Antarctic Zone and the Atlantic sectorof the Subantarctic Zone. (Received 13 November 1986;     

Ecological investigations on the zooplankton community of Balsfjorden, northern Norway: population dynamics of the euphausiids Thysanoessa inermis (Kroyer), Thysanoessa raschii (M.Sars) and Meganyctiphanes norvegica (M.Sars) in 1976 and 1977

The population dynamics of the euphausiids Thysanoessa inermis(Kröyer), T. raschii (M.Sars), and Meganyctiphanes norvegica(M.Sars) have been followed in Balsfjorden in 1976 and 1977.Seasonal variations in length-frequency distributions, growthin carapace length, sex-ratio, and spermatophore productionand attachment are presented and discussed in relation to changesin hydrography and phytoplanlcton standing-crop. An annual generationof T. inermis and T. raschii was spawned in April and May. Eggsand larvae of M. norvegica were not found in Balsfjorden, indicatingthat recruitment occurs from outside the fjord. T. inermis andT. raschii reached maximum carapace lengths of 7–8 mmand 6–7 mm respectively and had life-spans of c. 2 years3 months. M. norvegica had a life-span of c. 2 years 6 monthsand reached a maximum carapace length of c. 12.5 mm. In bothT. inermis and T. raschii 0-group underwent the greatest lengthincreases from May to October, I-group from March to Augustand II-group from April to June. The population structure, growthpatterns and growth periods of M. norvegica were difficult todiscern. The phytoplanlcton cycle appears to be the dominantfactor regulating both growth and spawning of the Thysanoessaspp in Balsfjorden, while temperature has no obvious influence.     

SYSTEMATIC REVISION OF THE EPIMENIIDAE (MOLLUSCA: SOLENOGASTRES)

The species of Epimeniidae (Solenogastres: Cavi-belonia) arecompared and revised according to available type material. Structuresof particular interest include the differentiation of the foregut,the pharyngo-buccal nervous system and the blood cells. Sevenspecies are recognized in the family. Of these, six are placedin the genus Epimenia: E. australis (Thiele) (synonym Dinomeniaverrucosa Nierstrasz), E. ohshimai Baba, E. arabica Salvini-Plawen& Benayahu, and the three new species E. babai from offKyushu, Japan (synonym E. verrucosa in Baba 1939–1951),E. allohaemata from off Korea and E.indica from the Maldives. E. vixinsignis Salvini-Plawen is transferred to Epiherpia gen.nov. (Received 2 February 1996; accepted 19 September 1996)     

NUTRITION OF TRIDACHIA CRISPATA (MORCH) (SACOGLOSSA)

Autotrophic nutrition plays an important role in adult Tridachiacrispata in the western Atlantic Ocean and results from an endosymbioticassociation between the sacoglossan and the kleptoplastids ofChlorophyta. A series of living specimens 7-80 mm in length was studied inthe laboratory. After a body length of 10 mm has been attained,the parapodial lobes of the two sides meet and fuse. Microscopicexamination of faecal strings of specimens undergoing this transitionrevealed that algal remains were produced only by juvenilesless than 13 mm long. Larger specimens defaecated only rarelyand the diminutive faecal strings contained no recognizablealgal debris. This transition probably parallels the physiologicaltransition between juvenile heterotrophic nutrition and adultautotrophic nutrition. Microscopic examination of the radulae of transitional specimensshowed no diminution of the size, number or morphology of theteeth. This indicates that in an emergency heterotrophic nutritionmay be resumed. Growth rates of Tridachia were measured in the laboratory, withand without light and the provision of algal foods. Unfed animalslost weight rather rapidly in captivity, whereas those fed uponsuitable algae (Halimeda discoidea, Caulerpa verticillata, C.racemosa and Chaetomorpha sp) did not.Caulerpa sertularioideswas suitable for food for a limited time, but proved toxic afterabout a week. Of the other species tested, Caulerpa verticillatawas the least suitable, while Halimeda, Chaetomorpha and Caulerparacemosa were the best. Ironically, C. verticillata was theonly one of the algal species tested which is known to be takenin the natural diet in Floridean waters. These experiments confirmedthat heterotrophic feeding will be resumed in Tridachia if theculture-conditions do not favour autotrophic nutrition.     

PHYLLODESMIUM GUAMENSIS (NUDIBRANCHIA: AEOLIDOIDEA), A NEW SPECIES FROM GUAM(MICRONESIA)

A new species of Phyllodesmium (Aeolidoidea) from Guam (Micronesia)is described. Phyllodesmium guamensis n.sp. is characterizedby having two rows of denticles in the radular teeth, this beingdifferent from the previously described species of the genus.The shape of the teeth, however, is identical in all the speciesof the genus, and unique among aeolids. Furthermore, P. guamensispossesses a double row of cerata in the precardiac cluster andup to 10 post-cardiac ceratal rows. Also, P. guamensis showsa very dense accumulation of zooxanthellae in the ceratal digestivegland, which is ramified inside the cerata. This species feedson at least three species of the soft coral Sinularia: S. polydactyla,S. maxima and a third, undescribed species. The aeolid matchesthe colour of its prey and is cryptic on the soft coral surface. (Received 3 October 1996; accepted 28 April 1997)     

B型烟粉虱和温室白粉虱热激蛋白90基因（hsp90）的全长cDNA克隆与系统发育分析

B型烟粉虱Bemisia tabaci (Gennadius) biotype B和温室白粉虱Trialeurodes vaporariorum均为全球普遍发生的重要害虫。本研究以其他昆虫热激蛋白90基因（hsp90）保守区域设计兼并引物扩增两种粉虱hsp90中间片段, 然后利用RACE技术获得全长cDNA。温室白粉虱hsp90全长cDNA的开放性阅读框2 166 bp, 编码722个氨基酸; 烟粉虱hsp90全长cDNA的开放性阅读框2 160 bp, 编码720个氨基酸。两种粉虱HSP90的完整氨基酸序列相似性高达92.94％, 并均具有定义HSP90家族签名序列的5个氨基酸保守区域和末尾基序“MEEVD”。通过real-time PCR技术, 探测到两个基因在mRNA水平上皆能高温诱导表达。采用昆虫纲所有完整HSP90氨基酸序列进行Kimura双参数遗传距离分析并构建NJ进化树, 结果显示hsp90在昆虫纲低级阶元水平和高级阶元水平系统进化上能得到一个较理想结果。本研究结果为B型烟粉虱和温室白粉虱抗逆适应性研究提供基础, 并进一步验证保守的功能基因hsp90可以作为研究生物系统发育的手段之一     

氟虫脲对东亚飞蝗和中华稻蝗几丁质合成酶基因表达的影响

为了探讨氟虫脲可能的作用靶标及毒性机制, 本研究以重要农业害虫东亚飞蝗Locusta migratoria manilensis (Meyen)和中华稻蝗Oxya chinensis (Thunberg)为材料, 采用简并引物扩增中华稻蝗几丁质合成酶1基因（OcCHS1）的部分cDNA序列; 以氟虫脲浸渍法处理2龄中期中华稻蝗及1, 2和3龄东亚飞蝗若虫为处理组, 丙酮处理为对照组, 使用RT-PCR和实时荧光定量PCR方法分析氟虫脲对蝗虫几丁质合成酶基因mRNA表达的影响。结果获得的OcCHS1部分cDNA序列, 其长度为312 bp, 编码104个氨基酸, GenBank登录号为HM214491, 与东亚飞蝗几丁质合成酶1基因（LmCHS1）在氨基酸水平上相似度达95％。RT-PCR结果显示, 处理组几丁质合成酶1扩增带均强于对照组。实时荧光定量PCR结果表明: 与对照组相比, 处理组中华稻蝗2龄中期若虫OcCHS1 mRNA表达提高了1.02倍, 东亚飞蝗1, 2, 3龄若虫LmCHS1 mRNA表达分别提高了34%, 82%和89%, 差异显著（P<0.05）。分析基因表达提高的原因是几丁质合成受阻后基因表达水平的一种代偿性增加, 由此推测几丁质合成酶可能是氟虫脲作用的靶标之一。     

横断山地区果蝇三新种(双翅目：果蝇科)

横断山地区果蝇三新种（双翅目：果蝇科）张文霞,梁醒财（北京大学生命科学学院北京１００８７１）（中国科学院昆明动物研究所昆明６５０２２３）’果蝇属果蝇亚属Ｄｒｏｓｏｐｈｉｌａ（Ｄｒｏｓｏｐｈｉｌａ）的ｍｅｌａｎｄｅｒｉ种组由Ｗｈｅｅｌｅｒ１９４９年建立...     

Molecular phylogeny of mangrove oysters (Crassostrea) from Brazil

As a result of phenotypic plasticity, the cupped oysters (Crassostrea)are difficult to identify by means of their morphology. However,molecular DNA markers are a useful means of discriminating amongthese species. Cupped oysters are one of the most widely culturedmarine invertebrates and correct species identification is importantin aquaculture. Moreover, the molecular phylogeny of the genusCrassostrea and the subfamily Crassostreinae is still not clear.In order to identify the Brazilian cupped oysters and to clarifythe phylogenetic relationships of these species, we sequenceda fragment of mitochondrial DNA (16S rRNA gene) from 120 specimenscollected at nine different sites distributed along the Braziliancoast. The results identified two native species of oyster:Crassostrea gasar, from the Amazon to the Parnaíba delta;and Crassostrea rhizophorae, from the northeast (Fortim) tothe south of Brazil. An exotic Crassostrea species, closelyrelated to Indo-Pacific Crassostrea, was found in one locationin the north of Brazil. Crassostrea showed monophyly and theAtlantic oysters are clearly separated from the Indo-Pacificcluster. (Received 30 May 2006; accepted 12 April 2007)     

B型烟粉虱与温室白粉虱不同虫态的碱性磷酸酶性质比较

为了探明B型烟粉虱Bemisia tabaci B-biotype 和温室白粉虱Trialeurodes vaporariorum体内的碱性磷酸酶(alkaline phosphatase,ALP)在两者竞争替代中所起的作用,以对硝基苯磷酸二钠 (pNPP)为底物,采用个体测定和群体测定的方法,研究比较了2种粉虱不同虫态中该酶的性质。结果表明：2种粉虱的碱性磷酸酶比活力在整个发育历期均逐渐增加,成虫期达到最大。温室白粉虱2至4龄若虫（伪蛹）期的碱性磷酸酶比活力分别是B型烟粉虱对应龄期酶比活力的2.58、2.68和3.14倍; B型烟粉虱雌雄成虫的碱性磷酸酶比活力分别是温室白粉虱雌雄成虫酶比活力的1.24和1.26倍,且2种粉虱雌虫的酶比活力显著大于其雄虫。2种粉虱2龄若虫到成虫的碱性磷酸酶最适pH均为7.8,最适温度均为47℃;在1龄若虫中均未能检测到该酶活性。测定并比较2种粉虱不同虫态碱性磷酸酶动力学特征参数的结果显示,温室白粉虱碱性磷酸酶在3、4龄若虫的亲和力以及在2, 3, 4龄若虫的酶蛋白浓度均显著大于B型烟粉虱的对应值,而在成虫期2种粉虱的亲和力、酶蛋白浓度无差异,B型烟粉虱的活化能显著小于温室白粉虱。据此推测,B型烟粉虱利用碱性磷酸酶在若虫期进行组织骨化和生长发育不如温室白粉虱,但羽化为成虫后利用其进行解毒代谢则可能强于温室白粉虱。     

SYSTEMATIC REVISION OF PATELLOIDA PYGMAEA (DUNKER, 1860) (GASTROPODA: LOTTIIDAE), WITH A DESCRIPTION OF A NEW SPECIES

Patelloida pygmaea (Dunker) and its closely allied species,P. heroldi (Dunker) and P. conulus (Dunker) have caused nomenclaturalconfusion because of their variable shell morphology and distinctivehabitats. According to current nomenclature, these species ofPatelloida have been synonymized and treated as one specieswith two ecological forms. Patelloida pygmaea lives on the shellof Crassostrea gigas (Ostreidae), P. pygmaea form heroldi occurson intertidal rocks on sheltered shores and P. pygmaea formconulus is found on the shell of Batillaria multiformis (Batillariidae).Their taxonomic relationships and possible species status are,however, unclear. Using two mitochondrial genes (fragments ofCOI and 16S ribosomal RNA; total 1192 sites), we analysed 88specimens of P. pygmaea, P. pygmaea form heroldi and P. pygmaeaform conulus from 37 localities in East Asia. In the resultingmolecular phylogenetic trees, the specimens of Patelloida fallinto four clades with high bootstrap probabilities; these cladescorrespond taxonomically to P. pygmaea, P. conulus, P. heroldiand a fourth previously unrecognized taxon, Patelloida ryukyuensisn. sp., described here. A minimum-spanning network for 29 uniquemitochondrial COI haplotypes obtained from 45 specimens in thesame bay in central Japan form three distinct clusters, consistingof P. pygmaea, P. conulus and P. heroldi, respectively. Thissuggests that reproductive isolation has been established betweeneach group. A detailed examination of radular and shell morphologiesof the four taxa clarifies the morphological distinction betweenthese species. The four species form a rather young clade inthe genus Patelloida that diverged during the Pliocene. Theyprovide an example of habitat segregation in a restricted marineenvironment. (Received 21 December 2004; accepted 11 March 2005)     

Electron-probe Microanalysis Studies of Silicon in the Elongating Basal Internodes of Avena sativa (L.), Hordeum sativum (Jess.) and Triticum aestivum (L.)

Silicon deposits in the elongating basal internodes of almostmature, field grown specimens of Avena sativa, Hordeum sativumand Triticum aestivum were investigated using electron-probemicroanalysis. In A. sativa and H. sativum silicon was foundto be confined to the cells in the endodermal layer, being presentwithin the inner tangential and radial walls, and occasionallyin the outer tangential wall. In T. aestivum some silicon wasalso located in walls of cells surrounding the vascular bundles. The anatomy of the internodal tissues is discussed for the threespecies from light micrographs. The endodermal layer is discontinuousin A. sativa and H. sativum, in the former species it partlyextends around individual vascular bundles. In T. aestivum itforms a complete cylinder around the stelar region and alsoshows considerably more thickening of the inner tangential wallthan in the other species. The results are discussed in relation to the anatomy of theinternodal tissues and the possible function of silicon in theendodermis. Avena sativa L., Hordeum sativum Jess, Triticum aestivum L., oat, barley, wheat, silicon deposition, electron-probe microanalysis     

Nuclear DNA Content of 26 Orchid (Orchidaceae) Genera with Emphasis onDendrobium

2C DNA content values for 70 orchid species from 26 genera,including 37Dendrobiumspecies from eight taxonomic sections,were analysed using flow cytometry. The resulting nuclear DNAcontent values for species other thanDendrobiumranged from 1.91pg 2C^-1to 15.19 pg 2C^-1nuclei forCadetia tayloriandVanilla phaeantha,respectively.Dendrobiumnuclear DNA content values ranged from1.53 pg 2C^-1to 4.23 pg 2C^-1nuclei forD. cruentumandD. spectabile,respectively. DNA content measurements varied greatly withinDendrobiumsectionsLatouria and Spatulata. Nuclear DNA content values for the sixspecies analysed within Latouria ranged from 1.88 pg 2C^-1nucleiforD. macrophyllumto 4.23 pg 2C^-1nuclei forD. spectabile. NuclearDNA content values for the 16 species analysed within Spatulataranged from 1.69 pg 2C^-1nuclei forD. discolorto 4.05 pg 2C^-1nucleiforD. samoense. The least variation in DNA content was foundwithin the section Phalaenanthe, with nuclear DNA content valuesof 1.79 pg  2C^-1, 1.86 pg 2C^-1and 1.98 pg 2C^-1forD. bigibbum,D.affineandD. phalaenopsis, respectively.Copyright 1998 Annalsof Botany Company Orchidaceae,Dendrobium, flow cytometry, propidium iodide, nuclear DNA, genome size, 2C values.