The Hybrid Origin of Two Cultivars of Crocus (Iridaceae) Analysed by Molecular Cytogenetics including Genomic Southern and in situ Hybridization

The origin of the two common cultivars of Crocus, C. 'Stellaris'(2n = 2x = 10) and C. 'Golden Yellow' (2n = 3x = 14) was investigatedby fluorescent in situ hybridization using both total genomicDNA and cloned DNA sequences as probes. The clear differentiationbetween the chromosomes after genomic in situ hybridizationsupports the proposals of a hybrid origin of the cultivars andshows that they have the same parental genomes originating fromC. flavus (2n = 8) and C. angustifolius (2n = 12). C. 'Stellaris'has four chromosomes of C. flavus origin and six chromosomesof C. angustifolius origin. C. 'Golden Yellow' has eight chromosomesof C. flavus origin and six chromosomes of C. angustifoliusorigin. The number and location of 18S-5·8S-26S rRNAgenes on the chromosomes of the hybrids and of the parentalspecies agree with the results from the genomic probings. Hybridizationto Southern membranes also supports the hybrid origin of C.'Golden Yellow'.Copyright 1995, 1999 Academic Press Taxonomy, cytology, rDNA sites, in situ hybridization, Southern hybridization, Crocus     

FIELD STUDIES OF HOMING IN THE PULMONATE SLUG LIMAX PSEUDOFLAVUS (EVANS)

Excursions of Limax pseudoflavus (Evans) were recorded over9 days using time lapse cinematography. Excursions were madeat night, ending before sunrise, and were significantly morefrequent in wet than in dry weather. The homes of these slugsare species rather than population or individual specific. Animalstended to home upwind but the direction in which they left homewas not significantly correlated with wind direction. Trailfollowing may be involved in homing. All but one example ofhoming may be interpreted in terms of distant chemoreception,rheotaxis and trail following. Using these mechanisms alonea slug's best strategy for feeding and homing is discussed. (Received 15 March 1979;     

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.     

FORAGING AND SPAWNING RHYTHMS OF THE PULMONATE LIMPET SIPHONARIA SIRIUS (PILSBRY): SWITCHING OF ACTIVITY PERIOD BY A DIURNAL FORAGER

Foraging and spawning rhythms of the intertidal pulmonate limpetSiphonaria sirius were studied at Shirahama, Wakayama Prefecture,Japan. Continuous 24 h observations were made five times, andtwo series of daytimeobservations were conducted for over 10days almost successively. This species inhabited the lower intertidalzones and had a diurnal habit in spring to autumn. At springtide most marked individuals showed foraging activity when awashand submerged both in ebb and flood tides before and after thetime of lowest water. When the tide progressed towards neaps,the activity peaks became ca. 30 min later per day and smaller.A new activity peak appeared early in the morning at neap tidein waxinghalf moon, and in summer, many adult limpets copulatedduring the morning activity. Simultaneous spawning by such limpetsoccurred one or two days after the peak of copulation. S. siriusswitched the activity period from late evening back to earlymorning at neap tide. The adaptive significances of such activitypatterns are discussed focusing on the responses against daytimedesiccation and nocturnal aquatic predators. (Received 5 September 1994; accepted 30 October 1994)     

THE EARLY DEVELOPMENT OF THE MARINE PROSOBRANCH NASSARIUS (HINIA) RETICULATUS (LINNAEUS)

The early development up to the end of gastrulation of the marineprosobranch Nassarius (Hinia) reticula-tus (Linnaeus) has beenexamined by scanning and transmission electron microscopy. Thesynchrony of the cleavage divisions ends with the formationof the second quartet. The somatoblast 2d and the mesen-toblast4d appear earlier than the other micromeres of their quartets.From the 16- to the 32-cell stage the turret cells have an outgrowth.At the end of cleavage, Nassarius shows a typical sterroblastula.During gastrulation, the epibolic encirclement of the yolk macromeresby the micromeres is produced by an active flattening of themicromere cap and at the end of gastrulation the blastoporeis completely closed. The nuclei of the four yolk macromeresmigrate from the animal cell regions towards the vegetativepole. The development of Nassarius reticulatus is very similarto that of the related species llyanassa obsoleta (Say). (Received 19 December 1990; accepted 18 August 1991)     

SPERMOGENESIS AND SPERM STRUCTURE IN THREE SPECIES OF PATELLOIDA AND ONE SPECIES OF NIPPONACMAEA (PATELLOGASTROPODA: ACMAEOIDEA)

The spermatozoa of Patelloida profunda albonotata, P. saccharina,P. pygmaea and Nipponacmaea schrenkii (Lottiidae) are describedby transmission electron microscopy. All have ect-aquasperm,typical of invertebrates using external fertilization. The spermof all four species have a cylindrical nucleus (length: breadth> 4: 1 in P. p. albonotata and P. saccharina; <4: 1 inP. pygmaea and N. schrenkii) which tapers towards the roundedanterior end. All have an acrosome with a posterior acrosomallobe which extends into the centre of the subacrosomal space.In P. p. albonotata and P. saccharina the acrosomal contentsare undifferentiated and the posterior lobe extends to the nucleus,being separated from it by flocculent material. In P. pygmaeathe acrosomal contents are differentiated, the lobe is relativelyshort and the subacrosomal space is filled with material witha fibrous appearance. The acrosome of N. schrenkii is undifferentiatedand the posterior lobe is no more than a bulge. The sperm ofP. p. albonotata and N. sacchrina have a small (0.25 µmlong) cytoplasmic collar which surrounds the axoneme anteriorlywhereas in P. pygmaea and N. schrenkii the cytoplasmic collaris longer (1 µm) and is swollen by an electron-dense vesicle.The composition and function of this vesicle is unknown. Thespermatozoa of Patelloida and Nipponacmaea have structural featureswhich are similar to sperm of the Lottiidae providing some supportfor the placement of these genera in the Lottiidae as proposedby Lindberg & Hedegaard (1996) and Sasaki & Okutani(1993) respectively. The similarities of the sperm of P. pygmaeato N.schrenkii raise some doubts about the tax-onomic statusof the former species. Spermiogenesis in all four species issimilar to that described for other Acmaeoidea and Patelloidea.In P. pygmaea and N. schrenkii, however, in addition to theacrosomal vesicle, the Golgi body produces a number of electron-densevesicles which fuse and eventually form a single vesicle inthe collar of the mid-piece. (Received 24 October 1996; accepted 10 February 1997)     

ALLOZYME SIMILARITY OF ATLANTIC AND PACIFIC SPECIES OF LITTORINA (GASTROPODA: LITTORINIDAE)

Four Littorina species from the Pacific (L. sitkana, L. brevicula,L. mandshurica, L. squalida) and four from the Atlantic (L.mariae, L. obtusata, L. saxatilis and L. littorea) were comparedelectrophoretically using 17 loci. Analysis of genetic identities showed that there were threegroups. The first group comprises L. sitkana, L. mariae, L.obtusata and L. saxatilis The second group consists of L. breviculaand L. mandshurica and the third one includes L. squalida andL. littorea. Our results support Reid's hypothesis of the originof Atlantic littorines from two Pacific ancestors. (Received 18 December 1991; accepted 30 March 1992)     

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...     

Ribulose-1,5-bisphosphate carboxylase from plants adapted to extreme environments

The K_m and V_max of ribulose-1,5-bisphosphate carboxylase (RuBPCase)in selenium absorbing plants (Astragalus flavus Barn., Astragalusrafaelensis Barn. and Stanleya pinnata Bril.) were similar toRuBPCase from tomato (Lycopersicon esculentum L. var. tropic).The pH optima for RuBPCase activity was 8.0 for L. esculentumand A. flavus and 7.0 for A. rafaelensis and S. pinnata. TheActivation Energy (E) values for the enzymes were as follows:A.flavus (21.37), S.pinnata (19.85), A. rafaelensis (19.12)and L. escudentum (18.58). The energy of activation was higherfor the desert plants as compared to the tomato. The Arrheniusplot curves were linear to 50?C far the desert plants as comparedto 45?C for tomato. Enzyme kinetics of RuBPCase from halophytic plants (Salicorniapacifica Stand., var. utahensis (Tidestrom) Munz. and Salicorniarubra Nels.) indicated the enzyme was at least as sensitiveto NaCl concentrations as the enzyme from tomato. (Received November 9, 1976; )     

SEASONAL CYCLE AND POPULATION DYNAMICS OF THE SEA HARE APLYSIA OCULIFERA IN THE NORTHERN GULF OF EILAT (AQABA), RED SEA

Populations of the sea hare, Aplysia oculifera (Adams &Reeve, 1850) (Gastropoda: Opistho-branchia), were studied inthe northern coast of the Gulf of Eilat (Aqaba) between April1988 and March 1992. Recruitment occurred from December to February,synchronized with the blooming of green algae (Enteromorphaintestinalis and Ulva sp.). A single recruitment event occurredeach year, while a secondary recruitment was rarely, observedand was related to acute catastrophic disturbance of the habitat.Adult sea hares inhabited the inter- and subtidal zones fromDecember-January to April-June, feeding on E. intestinalis andUlva sp. Populations disappeared in April-June which coincidedwith disappearance of these green algae. Mean maximum body livemass of adult sea hares (MMBLM, that is the highest mean bodymass recorded at specific site within the season) ranged from0.77 to 33 g MMBLM, varied significantly among populations inhabitingthe various study sites, and was significantly and inverselycorrelated with water movement intensity. Abundance of sea haresvaried among sites and among years and was related to the amountof green algae during the recruitment season. ²Present address: Department of Biology, University of Haifaat Oranim, Tivon 36006, Israel. E-mail: plaut{at}research.haifa.ac.il (Received 29 April 1997; accepted 26 July 1997)     

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.     

REMOTE BIOMINERALIZATION IN DIVARICATE RIBS OF STRIGILLA AND SOLECURTUS (TELLINOIDEA: BIVALVIA)

Deposits composed of aragonite prisms, which were formed afterthe outer shell layer, have been found at the posterior steepslopes of divaricate ribs in two species of Strigilla and anothertwo of Solecurtus. These prisms have their axes oriented perpendicularto the outer shell surface and differ in morphology from fibresof the surface-parallel composite prisms forming the outer shell.They display crystalline features indicating that, unlike crystalsforming the outer shell surface, their growth front was free,unconstrained by the mantle or periostracum. These particulardeposits are called free-growing prisms (FGPs). In these generathe periostracum is clearly not the substrate for biomineralizationand, upon formation, does not adhere to the steep slope of ribs,but detaches at the rib peak and reattaches towards the posterior,just beyond the foot of the posterior scarps of ribs. In thisway, a sinus or open space developed between the internal surfaceof the periostracum and the outer shell surface along each steeprib slope. These spaces could remain filled with extrapallialfluid after the mantle advances beyond that point during shellsecretion. FGPs grow within this microenvironment, out of contactwith the mantle. Other species with divaricate ribs do not developFGPs simply because the periostracum adheres tightly to both ribslopes (which are never so steep as in Solecurtus and Strigilla).FGPs constitute one of the rare cases of remote biomineralizationin which aragonite is produced and direct contact with the mantlenever takes place. (Received 22 November 1999; accepted 20 February 2000)     

GENETIC SIMILARITY IS HIGH BETWEEN INTERCONTINENTAL DISJUNCT SPECIES OF SENECIO (ASTERACEAE)

Senecio flavus (Decne.) Schultz-Bip. of the Saharo-Arabian and Namibian deserts and Senecio mohavensis Gray of the Mojave and Sonoran deserts form a pair of closely related disjunct annual taxa. The two species exhibit slight morphological differences and have different ploidy levels: all North American populations examined are tetraploid, while African and Asian populations are diploid. Senecio flavus comprises two morphologically and geographically distinct subspecies, subsp. flavus and subsp. breviflorus Kadereit. Electrophoretic examination of 13 enzymes revealed that the subsp. breviflorus has two additional isozymes relative to subsp. flavus, and that 5. mohavensis has four additional isozymes relative to subsp. breviflorus. Senecio flavus subsp. breviflorus and S. mohavensis are identical at 20 of the 21 (I = 0.952) remaining homologous loci. This value is much higher than the genetic identity values observed in other taxa with disjunct intercontinental distributions such as members of Agastache, Datisca, Liriodendron, and Styrax. This suggests that the Senecio disjunction may be of recent origin. Senecio flavus subsp. flavus from North Africa and Namibia has lower genetic identity values with S. mohavensis (0.857 and 0.805, respectively), implicating S. flavus subsp. breviflorus as the progenitor of 5. mohavensis. The complete lack of heterozygosity confirms that the plants are highly autogamous, and thus could have attained their disjunct distribution through long distance dispersal.     

COMPARATIVE KARYOLOGICAL ANALYSIS OF FIVE SPECIES OF VIVIPARUS (GASTROPODA: PROSOBRANCHIA)

Karyological analysis was performed on Viviparus ater (Cristofori& Jan, 1832), V. acerosus Bourguignat, 1862, V. mamillatus (Kuster),V. viviparus (Linnaeus, 1758) and V. contectus (Millet, 1813),collected from different freshwater bodies of Switzerland, Hungary,Albania, Italy and Lithuania. The karyotypes of V. acerosusand V. mamillatus are described for the first time. The diploidnumber of chromosomes in V. contectus equals 14, whereas indiploid sets of other studied species, 18 chromosomes are present.The karyotype formula is in V. contectus (5m + 2sm, NF = 28,in V. ater, 7m + 1sm-m + 1 sm, in V. acerosus and V. viviparus,8m + 1sm, NF = 36, in V. mamillatus, 6m + 1m-sm + 1sm-m + 1sm,NF = 36. In females of V. ater, V. mamillatus and V. acerosus,the heteromorphism of chromosome pair no. 8 was observed, witha sex-determining mechanism — ZW female /ZZ male. Although,Z and W chromosomes are metacentric, significant differences(P > 0.05, or P > 0.001) in their size were determined.The interspecific significant differences (P > 0.05) in karyotypesof V. ater, V. mamillatus, V. acerosus and V. viviparus weredetected by using one-way ANOVA and Bonferronis Multiple Comparisontests. Only chromosomes of the pair no. 5 were of similar shapein all of these species. The smallest interspecific differencewas between V. viviparus and V. acerosus. The intraspecifickaryological differences in relative chromosome length and centromericindex of V. contectus from lakes Garda (Italy), Olauka andAsveja (Lithuania) were observed in the chromosome pair no.5. (Received 29 March 1999; accepted 19 October 1999)     

Spatio-temporal distribution and production of calanoid copepods in the central Baltic Sea

The aim of our study was the exploration of species-specificdistribution and production patterns of dominant copepods inthe Central Baltic Sea (Bornholm Basin). Spatio-temporal distribution,egg and secondary production were studied by means of net-samplingand egg production experiments from April to August 1999. Verticaland horizontal distribution patterns appeared to be linked witheach other and were primarily species-dependent. Both Acartiaspp. and Temora longicornis preferentially inhabited the upper30 m of the water column and the shallower marginal regionsof the Bornholm Basin. In contrast, the C4–5 and C6 ofPseudocalanus spp. preferentially inhabited the halocline region(50–70 m) and the deep central part of the area. Observeddifferences in horizontal distribution among these three copepodsappear to result from different depth preferences and depth-dependentwater circulation patterns. Egg production rates (EPR) clearlyexhibited seasonal differences with maximum EPR in May and minimumEPR in July. Mean EPR was significantly different between species,being highest in Acartia spp. and lowest in Pseudocalanus spp.The variability in EPR was related to differences in hydrographyand modelled food environment.     

中国的光肩星天牛类群

该文讨论我国光肩星天牛Anoplophoraglabrlpennis(Motschulsky)类群的外部形态和外生殖器的主要鉴别特征,寄主、地理分布、起源及其演化。光肩星天牛主要分布在山西吕梁山、太行山以东的广大平原地区,寄主广泛,主要有榆、复叶槭、杨、柳、五角枫等。黄斑星天牛主要分布在秦岭以北,山西吕粱山太行山以西的陕甘宁地区,向东已扩展到河南、河北;主要为害杨树,也为害柳、榆。四川星天牛主要分布于秦岭以南的西部地区,北限在陕西太白山到甘肃天水一带;主要为害柳。在秦岭以北到天水之间是黄斑星天牛和四川星天牛的重叠分布区,山西太行山两侧南北走向的狭长地带是光肩星天牛和黄肩星天牛重叠分布区,两个狭长地带交会处,大约在秦岭以北的陕西和(或)山西境内有三个种的重叠分布区域.在云、贵、川地区广泛分布着四川星天牛,至今还没有发现光肩星天牛、黄斑星天牛和蓝角星天牛,后者应该是一个值得怀疑的种。     

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)     

林氏果蝇线粒体DNA分析

本文对Tamura(1988)提纯mtDNA的方法进行改进,建立了林氏果蝇Drosophila lini 线粒体DNA大量制备的方法;对采自原产地台湾省的单雌晶系TAW3146.1的线粒体DNA用10种限制性内切酶进行了酶切,得出了林氏果蝇mtDNA的分子量大小为16.3kb;用双酶切法制作了林氏果蝇线粒体DNA酶切图谱,并与属于同一复合种组的D.Kikkawai的酶切图谱进行比较。所用的内切酶有XbaI、AvaI、EcoRV、ScaI、SacI、EcoR I、HindIII、PvuⅡ、BamHI、PstⅡ。     

THE ANATOMY OF PACHYDERMIA LAEVIS (ARCHAEOGASTROPODA: 'PELTOSPIRIDAE')

The anatomy of Pachydermia laevis Warén & Bouchet,1989 is investigated. It is a deep-sea gastropod and restrictedto hydrothermal vents of the East Pacific Rise. Its anatomyresembles that of Melanodrymia aurantiaca Hickman, 1984 (Melanodrymiidae)in most respects, except that its gonopericardial duct opensinto the renopericardial duct, not into the peri-cardial chamber,and that it lacks a copulatory organ. Examination of M. aurantiacamain confirms earlier work. The two species have a cerebralbuccal connective fused with the cerebral ganglion (not freefrom it), a synapomorphy that has not been described for anyother archaeogastropod. The investigation suggests that Melanodrymiaand Pachydermia are closely related and together with Cyathermiidaeand Neomphalidae form a monophyletic group within the Neomphalina.No evidence was found to support earlier speculations aboutclose relations of Neomphalina to Viviparoidea. (Received 10 January 1996; accepted 3 April 1997)