隐肋甲螨属在我国的发现及一新种记述(蜱螨亚纲：甲螨亚目，滑珠甲螨科)

Aoki (1970) erected the genusCosteremus with C. ornata Aoki as the type species. Fujikawa and Fujita (1985)described the second species C.Yezoensis. The present paper deals with a new species of Costeremus from China.The genus is recorded for the first time from China, as well as from the outsidearea of Japan.     

THE DIET AND PREY CAPTURE MECHANISM OF MELO MELO (PROSOBRANCHIA: VOLUTIDAE)

Laboratory experiments undertaken with the South China Sea volute,Melo melo, have shown that it is a specialized predator of othercontinental shelf predatory gastropods, notably Hemifusus tuba(Melongenidae) and Babylonia lutosa (Buccinidae). (Received 30 December 1985;     

Electrogenic Pump Current and ATP-Dependent H+ Efflux Across the Plasma Membrane of Nitellopsis obtusa

The correlation between the pump current and the ATP-dependentH⁺ efflux was examined in internodal cells of Nitellopsis obtusa.To control the cytoplasmic pH and ATP concentration, the tonoplastwas removed by intracellular perfusion with an EGTA-containingmedium. Two groups of perfused cells were prepared, one with1 mM ATP (+ATP cells) and the other without ATP but with hexokinaseand glucose (–ATP cells). The ATP-dependent H⁺ effluxwas calculated as the difference in H⁺ efflux between the +ATPand –ATP cells. Based on an electrically equivalent circuitmodel of the plasma membrane, the pump current was calculatedfrom the membrane potentials and the membrane resistances ofboth +ATP and –ATP cells. When the membrane potentialwas not too high (–220 mV), the ATP-dependent H⁺ current(19 mA m^–2) was almost equal to the pump current (20 mAm^–2) calculated from the electrical data. This indicatesthat the electrogenic pump current across the plasma membraneof Nitellopsis obtuse was mostly carried by H⁺. But when themembrane potential was high (–280 mV), the H⁺ currentwas lower than the pump current. The possible cause of thisdiscrepancy is discussed. (Received November 5, 1984; Accepted February 28, 1985)     

ROLE OF FOOD IN MASS CULTIVATION OF THE FRESHWATER SNAIL INDOPLANORBIS EXUSTUS, VECTOR OF ANIMAL SCHISTOSOMIASIS

For the mass cultivation of the tropical freshwater snail, Indoplanorbisexustus, primary intermediate host of animal schistosomiasis,three foods, spinach, sheep's liver and a synthetic food (M/sHindustan Lever's rat food) were evaluated. The effect of thesefoods on growth, sexual maturity, fecundity and mortality isconsidered in this study. It is concluded that synthetic foodis ideal for breeding and sheep's liver for the maintenanceof mass cultures of this snail. revised 27 August 1985;     

THE INFLUENCE OF HUMIDITY, PHOTOPERIOD, AND TEMPERATURE ON THE DORMANCY AND ACTIVITY OF HELIX LUCORUM L. (GASTROPODA, PULMONATA)

The dormancy of Helix lucorum from N. Greece is controlled primarilyby low humidity. Photoperiod and temperature have no directeffect, except in the anomalous combination of long cool daysor short hot days. Adults hibernate more readily than juveniles.The duration of hibernation (before rejection of the calcareousepiphragm) is only slightly shorter at high temperatures. (Received 15 December 1985;     

THE MORPHOLOGY, ULTRASTRUCTURE AND FUNCTION OF THE FEEDING APPARATUS OF SAYELLA FUSCA (C.B. ADAMS, 1839) (GASTROPODA: PYRAMIDELLIDAE)

Scanning and transmission electron microscopy in conjunctionwith histology and dissection were employed to investigate theforegut anatomy of Sayella fusca (C.B. Adams, 1839), a commonNew England pyramidellid snail. Certain aspects of the feedingapparatus of S. fusca, including the buccal pump and proboscisanatomy, depart from the characteristic pyramidellid plan. Somedifferences such as the position of the introvert/proboscisaperture and the common oral and stylet canal are shared withthe genera Turbonilla, Eulimella, and Pyramidella. Three characteristicsof the feeding apparatus are unique to S. fusca: (1) the buccalpump is not divided into two pouches but exists as a singlemuscular bulb; (2) the entire lumen of the buccal pump, notsimply a portion of it, possesses a cuticular lining; and (3)the salivary ducts never enter the muscular walls of the buccalpump. Histological studies of the salivary gland indicate thatthree types of secretory cells are intermittently distributedthroughout the entire gland rather than characterizing distinctregions as described for other members of the family Pyra-midellidae.In contrast to previous findings, the gland cells of S. fuscaexhibit a merocrine secretion. The taxonomic value of the buccalpump and proboscis morphology are discussed. ^*Present address: Dauphin Island Sea Lab, 101 Bienville Boulevard,Post Office Box 369–370, Dauphin Island, Alabama 36528USA. (Received 9 November 1993; accepted 1 October 1997)     

Quantitative Analysis of ATP-Dependent H+ Efflux and Pump Current Driven by an Electrogenic Pump in Nitellopsis obtusa

Internodal cells of Nitellopsis were made tonoplast-free byperfusion with a medium containing EGTA. Cytoplasmic concentrationsof solutes were controlled by a second perfusion with mediaof known composition. The electrogenic pump current (I_p), whichwas calculated from electrical data obtained from cells withand without ATP, was compared with the current carried by H⁺(I_H⁺) across the plasma membrane. A close correlation betweenI_p and I_H⁺ was found under various internal and external conditions.(1) I_p and I_H⁺ depended on the internal ATP and showed Michaelis-Mententype saturation curves. For I_p, K_m was 120 µM and themaximum current V_max was 15.1 mA m^–2, while for I_H⁺, K_mwas 160 µM and V_max was 16.6 mA m^–2. (2) I_p andI_H⁺ showed almost the same I_H²⁺ dependence. The Mg²⁺-dependentI_p was 19.5 mA m^–2, while the Mg²⁺-dependent I_H²⁺ was17.7 mA m^–2. (3) I_H²⁺ was maximal at an external pH of8 and decreased both in acidic and alkaline pH ranges. I_p wasnearly equal to I_H⁺ in the pH range between 8 and 5. (4) I_H⁺became maximal at an internal pH of 7.3, which is nearly thesame as the pH for maximal electrogenecity found by Mimura andTazawa (1984). All these facts support the idea proposed in our previous paper(Takeshige et al. 1985) that the electrogenic ion pump locatedin the plasma membrane of Nitellopsis is the H⁺ pump. ¹ Dedicated to Professor Dr. Erwin Bünning on the occasionof his 80th birthday. (Received June 21, 1985; Accepted December 20, 1985)     

THE ULTRASTRUCTURE OF CILIATED CELLS FROM THE SIPHON OF SOLEN CAPENSIS (MOLLUSCA, BIVALVIA)

The structure of ciliated cells from the siphon of Solen capensishas been studied by both scanning and transmission electronmicroscopy. Two types of ciliated cell, based on the numberand length of cilia have been described which resemble thosedescribed in Donax. Type I is characterized by having 26–57({macron}= 43, n = 50) cilia which are 2.5 µm in length;Type II has fewer cilia (5–10; {macron}= 7) which are5 µn long. Both are primary receptors. Estimations ofabundance show that receptors are most numerous on the tipsof the siphon tentacles (8.8 x 10³/mm²). (Received 15 January 1985;     

D-Proline Effect on L-Proline-Requiring Mutants in Zea mays (L.)

D-Proline and three proline analogs, L-hydroxyproline, L-azetidine-2-carboxylicacid and L-thiazolidine-4-carboxylic acid, were tested for theireffect on proline-requiring mutants (pro 1) of maize at theconcentrations used for phenotypic repair with L-proline. D-Prolinewas the only one that promoted pro 1 mutant growth and did notaffect the growth of normal siblings. The possible role of D-prolinein repairing pro 1 mutants is discussed. (Received February 15, 1985; Accepted July 2, 1985)     

AN ULTRASTRUCTURAL STUDY OF EUSPERMATOZOA, PARASPERMATOZOA AND NURSE CELLS OF THE COWRIE CYPRAEA ERRONES (GASTROPODA, PROSOBRANCHIA, CYPRAEIDAE)

The sperm duct of the cowrie Cypraea errones Linné containseuspermatozoa, paraspermatozoa and nurse celts, the latter bearingclumps of attached euspermatozoa. Nurse cell/euspermatozoa associationshave been described in certain littorinacean gastropods, butare previously unrecorded in the Cypraeacea. Euspermatozoa ofC. errones resemble those of many other mesogastropods and someneogastropods (for example members of the Strombidae, Epitoniidae,Naticidae, Volutidae; shared features include structure of theacrosome, nucleus, glycogen piece, and helically coiled midpieceelements). However in C. errones, radially arranged paracrystallinefibres partly occupy the space between adjacent midpiece elements.Paracrystalline material is only rarely observed in spermatozoaof prosobranch gastropods and in all cases (including C. errones),is readily discernible form the complex paracrystalline layerspresent in the mitochondria) derivative of opisthobranch andpulmonate spermatozoa. Paraspermatozoa of C. errones are elongate,vermiform cells containing: multiple axonemes (bunched anteriorly,peripherally distributed posteriorly); granulated deposits (anteriorly);numerous dense vesicles (posteriorly) and scattered mitochondria(elongate, with parallel cristae). The axonemal attachment complexesfuse apically to form a sharp, conical structure. Comparisonwith available electron microscopic and light microscopic accountsof prosobranch euspermatozoa and paraspermatozoa suggests closeties between the higher Mesogastropoda (with which the Cypraeidaeshould be included) and the Neogastropoda. Further researchwill be required to determine whether the paracrystalline fibresobserved in euspermatozoa of C. errones are characteristic ofthe Cypraeidae or perhaps shared with the Ovulidae or Triviidae. (Received 26 November 1985;     

SNAIL FARMING: A SURVEY OF BREEDING MANAGEMENT, HYGIENE AND PARASITISM OF THE GARDEN SNAIL, HELIX ASPERSA MULLER

Fifteen farms in 1984 and twenty in 1985 were investigated forbreeding management, hygiene and parasitism. Farm hygiene didnot seem to play an important role on the breeding performancesin our samples. Nematodes were the most frequent parasites:Alloionema appendiculatum were equally prevalent among juvenileand adult snails whereas Angiostoma aspersa and Nemhelix bakeriwere found mostly in reproductive adults. The presence of nematodes,assessed by coproculture, was negatively related to breedingperformances     

ALLOZYME VARIATION IN SOME POPULATIONS OF THE FRESHWATER SNAILS LYMNAEA PEREGRA, L. AURICULARIA AND L. STAGNALIS (GASTROPODA: PULMONATA)

Three species of the genus Lymnaea (Gastropoda, Pulmonata, Basommatophora)were examined for genetic variation at 11 enzymatic loci insamples collected in Brittany (North-Western France). Variabilitywas greatest in L. percgra, but the limited area of samplingdid not allow specific inferences. The UPGMA clustering of unbiasedgenetic distances (Nei, 1978) isolated first L. auriculariasamples, and secondly the single L. stagnalis sample from theL. peregra set. This scheme of relationships was opposed tothe identification of alleles shared by the three species atthe studied loci Analysis of L. peregra population structure by F-statistics(Weir & Cockerham, 1984) suggested high inbreeding and raisedthe possible role of self-fertilization. The contradiction betweenhigh variability and high homozygosity is discussed. Furthermore,population differentiation was rather weak (although statisticallysignificant), despite some remarkable differences among loci.Nm estimates using Wright's (1951) and Slatkin's (1985) methodsrevealed a gene flow unable to prevent the effect of geneticdrift among populations. The relative homogeneity of populationswith weak genetic exchange is discussed (Received 24 May 1993; accepted 21 March 1994)     

REPRODUCTIVE CYCLES OF CERASTODERMA GLAUCUM(BRUGUIERE) AND C. EDULE (L.) WITH SPECIAL REFERENCE TO THE EFFECTS OF THE 1981-82 SEVERE WINTER

Gonadal changes in two species of Cerastoderma occurring indiscrete populations in South Wales were monitored by stereologicalanalysis during the breeding seasons of 1981 and 1982. Fecundityand spawning efficiencies were determined quantitatively. Therelationship between reproductive activity and changes in meatcondition are discussed. Both species are opportunistic breeders. Their normal patternsof reproduction are similar, consisting of minimum activityin winter and peak activity during spring/early summer. Thetwo species were affected differently by the severe winter of1981–82—C. glau-cum exhibited a single, ‘epidemic’spawning and resumed gametogenesis after a 4-month resting period.C. edule adopted a ‘polycyclic’ pattern withouta resting period. Both of these unusual reproductive strategies,augmented by reduced predation resulted in heavy spatfalls. (Received 20 March 1985; revised 20 March 1985;     

EFFECTS OF WOUND HEALING ON ZINC DISTRIBUTION AND ALKALINE PHOSPHATASE ACTIVITY OF HELIX ASPERSA (GASTROPODA: PULMONATA)

Helix aspersa were loaded with ⁶⁵zinc and after 2 and 5 daysstarvation there was no significant reduction in the zinc concentrationof the digestive gland and shell. Wounding of the optic tentacle,foot tissue and partial shell removal of H. aspersa resultedin deposition of ⁶⁵zinc in the wound area. Alkaline phosphataseshowed no increase in concentration at the sites of wounding. (Received 15 October 1985;     

The Role of the Plasma Membrane Proton Pump in Short-term pH Regulation in the Aquatic Liverwort Riccia fluitans L.

The question is raised, to what extent is the plasma membraneproton pump involved in short-term pH regulation of plant cells?For this purpose the cytosolic pH (pH_c) of Riccia fluitans rhizoidand thallus cells has been measured continuously using pH-sensitivemicroelectrodes (Felle and Bertl, 1986a). It is demonstratedthat pH perturbations (light, weak acids, external pH) in bothdirections are completely or at least partly eliminated withinminutes. The pH_c recovery occurs regardless of the activationstate of the proton pump. The proton pump reacts to changesin cytosolic pH as expected, namely with increased proton extrusionto decreased pH_c; however, changes in pump activity (fusicoccin,CCCP, cyanide) do not necessarily result in cytosolic pH shifts.These results suggest that several proton transport mechanisms(including the proton pump) co-operate in the restoration ofa perturbed cytosolic pH. It is concluded, however, that theproton pump, although most important for the energization ofthe plasma membrane, does not regulate cytosolic pH.     

Efflux of photosynthate and acid from developing seed coats of Phaseolus vulgaris L.: a chemiosmotic analysis of pump-driven efflux

Seed coats of Phaseolus vulgaris L. unload photosynthetic products,mineral ions and acid into the apoplastic space surroundingthe embryo. We report measurements, on detached seed coats,of the rates of unloading of photosynthates, ions and acid atdifferent external pH and in the presence of treatments intendedto alter the rate of proton pumping. We also report measurementsof membrane potential difference (PD) and of cytoplasmic pHunder the same conditions, measurements which have allowed usto validate the treatments we used and to investigate functionalrelationships between membrane processes. A chemiosmotic model of the seed-coat cell membrane is proposed,in which sucrose efflux and acid efflux are both driven by theproton pump. Sucrose efflux is proposed to occur by sucrose/protonantiport driven by the proton-motive force (PMF), and acid effluxto occur by pumped protons accompanied by a passive efflux ofanions. We use our measurements to estimate the net efflux ofsucrose on the antiporter and the total efflux of protons onthe pump. We have tested the model by using experimental treatments designedto manipulate the pump rate as the independent variable. Underthese conditions, and assuming the model is correct, the pumprate determines the cytoplasmic pH. Over the range covered byour experiments the net sucrose efflux is dependent on externaland cytoplasmic pH, the latter having the major role. The effluxof acid, under the same treatments, depends primarily on theproton pump rate, and was found to be well fitted by a quadraticfunction of pump rate. This means that, as pump rate increases,an increasing proportion of the pump output is used by acidefflux and a decreasing proportion by sucrose antiport. The membrane PD, although an important component of the PMF,does not appear to function in rate control of net sucrose orof acid efflux, since neither efflux is correlated with membranePD under our treatments which vary the pump rate. The PD correlateswell with external potassium concentration, and seems largelydetermined by the diffusion of potassium ions and anions. Key words: Phaseolus vulgaris L, photosynthate efflux, proton pump, sucrose/proton antiport, seed coat, membrane transport model     

A NEW SPECIES OF LITHOPHAGA (BIVALVIA: LITHOPHAGINAE) BORING CORALS IN THE CARIBBEAN

A new species of Lithophaga is described as a small lithophaginemussel exclusively boring Madracis mir-abilis, M. decactis andM. formosa in Jamaica. The shell, musculature and pallial glandsshow modifications for live coral boring similar to those ofIndo-Pacific species of the genus. However, both the boringand posterior pallial glands are more primitive than other speciesexamined to date, interpreted as indicative of a more recentadaptation to life in a living coral habitat by this species. ^*Contribution No.359 of the Discovery Bay Marine Laboratory,University of the West Indies (Received 23 April 1985;     

Comparative Fungitoxic and Plant Growth Regulating Properties of Triazole Derivatives

The triazol derivatives, S-3307, S-3308, triadimefon, triadimenoland paclobutrazol are recommended for use as either fungicidesor plant growth regulators. However, in varying degrees theyexhibit both properties. In a comparative study with 5 differentfungi, S-3308 followed by S-3307 were the most fungitoxic (invitro) whereas S-3307 and paclobutrazol were the most activeplant growth retardants in bean (Phaseolus vulgaris L.) andKentucky bluegrass (Poa pratensis L.). (Received September 24, 1985; Accepted November 26, 1985)