THE UNIQUE,MICRORETICULATE CYST OF THE NAKED DINOFLAGELLATE GYMNODINIUM CATENATUM1

Gymnodinium catenatum Graham is an unarmored dinoflagellate responsible for episodes of paralytic shellfish poisoning. This species forms a resting cyst that is unique in several ways. The outer surface of the spherical, brownish cyst is microreticulate and composed of hundreds of 1-3 μm polygons. In several regions, these polygons are smaller, more uniform in shape, and oriented in distinct bands that define morphological features. These features on the cyst reflect the cingulum, sulcus, flagellar pore complex, and acrobase of the motile stage precursor to the cyst. The archeopyle is irregularly but extensively developed. Its margin is generally smooth and extends almost completely around the circumference of the cyst, though not consistently in the plane of the equator. The cyst wall is resistant to acetolysis and standard palynological preparation techniques. Gymnodinium catenatum Graham is emended to include the details of the cyst stage. The significance of this cyst is that it is the first described cyst of a naked dinoflagellate that bears oriented surface ornamentation reflecting features of the motile dinoflagellate. Its microreticulate surface ornamentation is unique to dinocysts, naked or armored, living or fossilized. Resistance of the cyst wall to harsh processing techniques suggests the presence of sporopollenin-like material commonly associated with cysts of armored dinoflagellates. From an ecological standpoint, the existence of a G. catenatum cyst has important implications with respect to species bloom dynamics and geographic distribution. In addition, the distinct differences between this cyst and those of the armored saxitoxin-producing gonyaulacoid species argues against a proposed evolutionary linkage.     

Gymnodinium catenatum Graham (Dinophyceae)in Europe: a growing problem?

The microreticulate resting cyst of the potentially toxic, chain-forming,unarmoured neritic dinoflagellate Gymnodinium catenalum Graham1943. the planktonic stage of which is not known from NorthEuropean waters, is reported for the first time from recentGerman coastal sediments of the North Sea and Baltic Sea. Insandy mud sediments of the German Bight, a maximum of 8 5 livingcysts cm^–3 were found. In Kiel Bight sediments G.catenalumwas found in maximum concentrations of 17.0 living cysts cm^–3.In surface waters of the German Bight resuspended G catenatumcysts were observed at concentrations of up to 3.6 cysts l^–1.Successful germination experiments conducted with natural seawatershow that the occurrence of a vegetative form of G.catenatumin northern Europe is very likely. The present study highlightsthat cyst surveys provide an important tool for the evaluationof areas with potential toxicity problems, as they may indicatethe presence of hitherto overlooked species in the water column.     

Reconstructing the history of an invasion: the toxic phytoplankton species <Emphasis Type="Italic">Gymnodinium catenatum</Emphasis> in the Northeast Atlantic

The phytoplankton species Gymnodinium catenatum is responsible for major worldwide losses in aquaculture due to shellfish toxicity. On the West coast of the Iberian Peninsula, toxic blooms have been reported since the mid-1970s. While the recent geographical spread of this species into Australasia has been attributed to human-mediated introduction, its origin in the Northeast Atlantic is still under debate. Gymnodinium catenatum forms a highly resistant resting stage (cyst) that can be preserved in coastal sediments, building-up an historical record of the species. Similar cyst types (termed microreticulate) are produced by other non-toxic Gymnodinium species that often co-occur with G. catenatum. We analysed the cyst record of microreticulate species in dated sediment cores from the West Iberian shelf covering the past ca. 150 years. Three distinct morphotypes were identified on the basis of cyst diameter and paracingulum reticulation. These were attributed to G. catenatum (35.6–53.3 μm), G. nolleri (23.1–36.4 μm), and G. microreticulatum (20.5–34.3 μm). Our results indicate that G. catenatum is new to the NE Atlantic, where it appeared by 1,889 ± 10, expanding northwards along the West Iberian coast. The earliest record is from the southernmost sample, while in the central Portuguese shelf the species appears in sediments dated to 1,933 ± 3, and in the North, off Oporto, in 1,951 ± 4. On the basis of the cyst record and toxic bloom reports, we reconstruct the invasive pathway of G. catenatum in the NE Atlantic. Although human-mediated introduction cannot be discarded, the available evidence points towards natural range expansion, possibly from NW Africa.     

VEGETATIVE REPRODUCTION AND SEXUAL LIFE CYCLE OF THE TOXIC DINOFLAGELLATE GYMNODINIUM CATENATUM FROM TASMANIA,AUSTRALIA1

The toxic, chain-forming dinoflagellate Gymnodinium catenatum Graham was cultured from vegetative cells and benthic resting cysts isolated from estuarine waters in Tasmania, Australia. Rapidly dividing, log phase cultures formed long chains of up to 64 cells whereas stationary phase cultures were composed primarily of single cells (23-41 pm long, 27-36 pm wide). Vegetative growth (mean doubling time 3-4 days) was optimal at temperatures from 14.5-20° C, salinities of 23-34% and light irradiances of 50-300 μE·m^?2·s^?1. The sexual life cycle of G. catenatum was easily induced in a nutrient-deficient medium, provided compatible opposite mating types were combined (heterothallism). Gamete fusion produced a large (59-73 μm long, 50-59 μm wide) biconical, posteriorly biflagellate planozygote (double longitudinal flagellum) which after several days lost one longitudinal flagellum and gradually became subspherical in shape. This older planozygote stage persisted for up to two weeks before encysting into a round, brown resting cyst (42-52 μm diam; hypnozygote) with microreticulate surface ornamentation. Resting cysts germinated after a dormancy period as short as two weeks under our culture conditions, resulting in a single, posteriorly biflagellate germling cell (planomeiocyte). This divided to form a chain of two cells, which subsequently re-established a vegetative population. Implications for the bloom dynamics of this toxic dinoflagellate, a causative organism of paralytic shellfish poisoning, are discussed.     

Morphology,phylogeny and toxin profiles of Gymnodinium inusitatum sp. nov., Gymnodinium catenatum and Gymnodinium microreticulatum (Dinophyceae) from the Yellow Sea,China

Four Gymnodinium species have previously been reported to produce microreticulate cysts. Worldwide, Gymnodinium catenatum strains are conservative in terms of larger subunit (LSU) rDNA and internal transcribed spacer region (ITS) sequences, but only limited information on the molecular sequences of other species is available. In the present study, we explored the diversity of Gymnodinium by incubating microreticulate cysts collected from the Yellow Sea off China. A total of 18 strains of Gymnodinium, from three species, were established. Two of these were identified as Gymnodinium catenatum and Gymnodinium microreticulatum, and the third was described as a new species, Gymnodinium inusitatum. Motile cells of G. inusitatum are similar to those of Gymnodinium trapeziforme, but they only share 82.52% similarity in LSU sequences. Cysts of G. inusitatum are polygonal in shape, with its microreticulate wall composed of approximately 14 concave sections. G. microreticulatum strains differ from each other at 69 positions (88.00% similarity) in terms of ITS sequences, whereas all G. catenatum strains share identical ITS sequences and belonged to the global populations. Phylogenetic analyses, based on LSU sequences, revealed that Gymnodinium species that produce microreticulate cysts are monophyletic. Nevertheless, the genus as a whole appears to be polyphyletic. Paralytic shellfish toxins (PSTs) were found in all G. catenatum strains tested (dominated by 11-hydroxysulfate benzoate analogs and N-sulfocarmaboyl analogs) but not in any of the G. microreticulatum and G. inusitatum strains. Our results support the premise that cyst morphology is taxonomically informative and is a potential feature for subdividing the genus Gymnodinium.     

Temperature tolerances of toxic dinoflagellate cysts: application to the treatment of ships' ballast water

Using toxic dinoflagellates and their resistant resting cysts as model organisms, we demonstrate the potential of heat treatment as a method to minimise the transport of harmful aquatic organisms via ships' ballast water. Vegetative dinoflagellate cultures of Gymnodinium catenatum could be readily killed using temperatures as low as 35 °C and treatment times in the range 30 minutes to 5 h. The resistant resting cysts (hypnozygotes) of G. catenatum were killed after 2 h at 35 °C and the cysts of Alexandrium catenella were killed after 4.5 h at 38 °C . A careful assessment of various waste heat sources on the BHP bulk carrier Iron Whyalla has confirmed the practicability of this approach, and a successful pilot heat treatment plant was trialled on-board ship in April 1997.     

Early warning of toxic dinoflagellate blooms of Gymnodinium catenatum in southern Tasmanian waters

Blooms of the toxic dinoflagellate Gymnodinium catenatum (acausative organism of paralytic shellfish poisoning) in theDerwent and Huon estuaries of southern Tasmania, Australia,are predictable, annually recurrent events in the period Januaryto June (late summer to early winter). However, their spatialdistribution, duration and magnitude exhibit significant interannualvariability. High shellfish toxicities in 1986, 1991 and 1993(>8000 µ.g paralytic shellfish poisoning per 100 gshellfish meat) also coincided with the greatest spatial extentof shellfish toxicity (up to 35 shellfish farms closed for periodsup to 6 months). An exploratory analysis of the results of ashellfish toxin monitoring programme conducted from 1986 to1994, and of available hydrological and meteorological datafor the region, indicates that a significant G.catenatum bloomin Tasmanian waters can only develop within a permissive seasonalwater temperature window (>14°C at the time of bloominitiation) requiring a rainfall event as a trigger (Huon Riverdischarge, measured at Frying Pan Creek, must exceed 100 000megalitres over a 3-week period) and a calm stable water columnfor sustained development (windspeed <5 m s^–1 for periodsof 5 days or more). Once established, dinoflagellate populationsare subject to disturbance by turbulence caused by high windstress;this explains the incidence in some years of multiple shellfishtoxicity peaks. In winter months declining water temperatures(<10°C) and increasing windstress are responsible forthe termination of seasonal dinoflagellate blooms.     

GENETIC VARIATION AMONG STRAINS OF THE TOXIC DINOFLAGELLATE GYMNODINIUM CATENATUM (DINOPHYCEAE)

The toxic dinoflagellate Gymnodinium catenatum Graham has formed recurrent toxic blooms in southeastern Tasmanian waters since its discovery in the area in 1986. Current evidence suggests that this species might have been introduced to Tasmania prior to 1973, possibly in cargo vessel ballast water carried from populations in Japan or Spain, followed by recent dispersal to mainland Australia. To examine this hypothesis, cultured strains from G. catenatum populations in Australia, Spain, Portugal, and Japan were examined using allozymes and randomly amplified polymorphic DNA (RAPD). Allozyme screening detected very limited polymorphism and was not useful for population comparisons; however, Australian, Spanish, Portuguese, and Japanese strains showed considerable RAPD diversity, and all strains examined represented unique genotypes. Multidimensional scaling analysis (MDS) of RAPD genetic distances between strains showed clear separation of strains into three nonoverlapping regional clusters: Australia, Japan, and Spain/Portugal. Analysis of genetic distances between strains from the three regional populations indicated that Australian strains were almost equally related to both the Spanish/Portuguese population and the Japanese population. Analysis of molecular variance (AMOVA) found that genetic variation was partitioned mainly within populations (87%) compared to the variation between the regions (8%) and between populations within regions (5%). The potential source population for Tasmania’s introduced G. catenatum remains equivocal; however, strains from the recently discovered mainland Australian population (Port Lincoln, South Australia, 1996) clustered with Tasmanian strains, supporting the notion of a secondary relocation of Tasmanian G. catenatum populations to the mainland via a shipping vector. Geographic and temporal clustering of strains was evident among the Tasmanian strains, indicating that genetic exchange between neighboring estuaries is limited and that Tasmanian G. catenatum blooms are composed of localized, estuary-bound subpopulations.     

Dinoflagellate cyst production at a coastal Mediterranean site

To assess the diversity and seasonality of dinoflagellate cystproduction, surface sediment and trap samples were studied inthe Gulf of Naples (Mediterranean Sea). A total of 59 differentcyst morphotypes were recorded. At the stations within the 70m isobath, sediment assemblages were dominated by calcareousPeridiniales (66–79%), while at the deepest stations non-calcareousPeri-diniales attained the highest percentages (40–49%).The sediment trap sampling, carried out fortnightly over twoannual cycles, revealed high production rates (up to 1.7 x 10⁶cysts m^–2 day^–1) from spring to late autumn of bothyears, with a distinct seasonal production pattern. Althoughrather similar in species composition, the total cyst flux differedmarkedly between the 2 years (1.26 and 0.55 x 108 cysts m^–2year^–1, respectively). Species-specific production patternswere observed: some species formed cysts over several months,others in restricted periods of the year. Cyst-forming speciesconstituted a small part of the planktonic dinoflagellate populationsrecorded in the area. A coupling between the trap material andsurface water plankton was observed for calcareous Peridiniales.This sampling approach allowed the detection of some speciesnever recorded before in the gulf, including two potentiallytoxic species: Alexandrium andersoni and Gymnodinium catenatum-likespecies.     

Cysts of Danish Gymnodinium nolleri Ellegaard et Moestrup sp. ined. (Dinophyceae): studies on encystment, excystment and toxicity

Life cycle dynamics of Gymnodinium nolleri Ellegaard et Moestrupsp. ined. were studied under different temperature and nutrientconditions. Five culture strains originating from cysts foundin Danish marine sediments were used for the experiments. Bothencystment and excystment were found to vary with temperature.Maximal encystment occurred at 22–28°C, with no cystsformed below 13°C or above 33°C. Cyst production wasslightly higher under phosphorus limitation than under combinednitrogen and phosphorus limitation. Maximal excystment occurredat 26.5°C with negligible excystment under 11°C andover 35°C. The resting period for cyst maturation was typically3–4 weeks. Cysts produced under both phosphorus and nitrogenlimitation were tested for paralytic shellfish poisoning (PSP)toxins by HPLC, and none were detected. It remains unclear whyvegetative cells of this species have not yet been recordedin plankton samples from Scandinavia, despite the widespreaddistribution of the cysts.     

Intraspecific variation in the selenium requirement of different geographic strains of the toxic dinoflagellate Gymnodinium catenatum

The requirement for selenium (IV) was assessed in five strainsof the toxic dinoflagellate Gymnodinium catenatum Graham, representingthree populations from Tasmania (Australia), as well as oneeach from Japan and Spain. Strains were grown in nutrient-enrichedsea water medium with 10^–9 M selenium added as selenite(H₂SeO₃), or with no added selenium, and monitored for growthand cell yield. Strains exhibited different selenium (Se) requirements,as evidenced by (i) a decrease in exponential growth rate (10–20%)and cell yield (up to 80%) (Japanese strain); (ii) a decreasein cell yield only (Tasmania Derwent Estuary 1987, TasmaniaHuon Estuary and Spanish strains); and (iii) no decrease ingrowth or cell yield (Tasmania Derwent Estuary 1993 strain).Variation in the response to Se deficiency was greatest betweenthe two strains isolated from the Derwent Estuary, Tasmania,in different years (1987 and 1993) and less between Tasmanianstrains from different localities (Huon and Derwent Estuariesare 50 km apart) or between Tasmanian and Japanese or Spanishstrains. Strain variability in micro-nutrient responses suchas described here may provide a partial explanation for differentbloom patterns exhibited by the same dinoflagellate taxon underapparently similar environmental conditions.     

Red tide assemblage formation in an estuarine upwelling ecosystem: Ria de Vigo

Red tides are conspicuous in the upwelling system of Galicia(NW Iberian Peninsula). At present, there are conflicting hypothesesabout the generation site of these phytoplankton assemblages.It is interesting to know whether the rias can be sites of redtide formation or if they act only as accumulation sites ofpopulations advected from shelf waters. A study in the Ra deVigo, carried out during late September 1990, showed the developmentof a red tide assemblage, composed of Alexandrium affinis, Ceraiiumfusus and Gymnodinium catenaium, during a 2 week upwelling-downwellingcycle. Growth occurred at the bottom of the thermocline-topof the nutricline. Above this assemblage, a diatom assemblage(large diatoms) was blooming. Prior to the formation of thered tide, a subsurface chlorophyll maximum made up of smalldiatoms (Nilzschia f. seriaia, Chaeloceros socialis), smallflagellates (<30 µm) and small gymnodinid forms (<30µm) was observed. In the nutrient-depleted upper layer,several autotrophic and large heterotrophic dinoflagellatesdominated. It is suggested that the ratio between the velocityof upward water movement and the depth of the stratified upperlayer (flushing rate, day^–1) is the critical parameterwhich triggers active phytoplankton growth. It can be concludedthat upward water velocities of {small tilde}2.5 m day^–1and a stratified upper layer of 10 m depth (flushing rate 0.25day^–1) are the main physical constraints for red tidedevelopment.     

Reproductive phenology of the introduced kelp <Emphasis Type="Italic">Undaria pinnatifida</Emphasis> (Phaeophyceae,Laminariales) in Port Phillip Bay (Victoria,Australia)

A thorough understanding of the reproductive phenology of introduced species is crucial for effective management and control. Undaria pinnatifida is an invasive macroalga from the Northwest Pacific which has been recently introduced into three countries in the Southern Hemisphere: Australia, New Zealand and Argentina. Reproductive phenological studies in Port Phillip Bay, Australia, were undertaken and compared with other populations in the Southern Hemisphere, especially with those from Tasmania which were suspected to be very different. The growth season began earlier in Port Phillip Bay than in Tasmanian populations, and abundance was higher. Growth rates were lower in Port Phillip Bay, but this might be due to the different morphology of both populations. The maximum spore release competency of U. pinnatifida in Port Phillip Bay was 12.1 × 10⁵ spores cm⁻² h⁻¹ which is 20 times the maximum obtained in Tasmania (0.6 × 10⁵ spores cm⁻² h⁻¹). For most of the growth season, spore release competency ranged between 2 and 3 × 10⁵ spores cm⁻² h⁻¹, 3–5 times more than in Tasmania. Undaria pinnatifida has not been established outside Port Phillip Bay in continental Australia, but a precautionary approach should be undertaken in order to avoid further spread. Monitoring for early detection and removal of immature sporophytes prior to spore release seem to be the best options. This monitoring should be continuous since new recruits may appear throughout the growth season (April–February) and it should be combined with informative programmes to reduce the chances of spread.     

Improved fruiting of Coprinus atramentarius using cold-shock treatment during growth

Coprinus atramentarius was grown on two commercial composts at a constant 20°C or with a cold shock (25°C20°C) after 10 days. Cold shock was required for it to form fruiting bodies.The authors are with the University of Western Sydney, Hawkesbury, School of Horticulture, Locked Bag 1, Richmond NSW 2753, Australia     

Growth and genotypes of Echinococcus granulosus found in cattle imported from Australia and fattened in Japan

At the abattoir on study in Miyazaki, Japan, 9537 imported cattle from Australia in average were slaughtered annually in the last 5 years (2006 to 2010) and hydatid cysts were constantly detected in about 1.8% of the cattle. In order to assess the risk of Echinococcus granulosus delivered to Japan by imported cattle, 250 cysts found in 103 cattle at the abattoir were examined for their biological characteristics and genotypes. The cattle slaughtered were imported from Australia at an age of 10-12 months old and fattened for 17-18 months in Japan. The cysts showed their size ranging from 4 to 108 mm and were mainly found in the lung. Mature protoscoleces were detected in the three largest cysts, all were of the G1 genotype. Most of the other cysts contained clear cyst fluid and had thin laminated layer with no protoscoleces. The finding implies a potential risk of E. granulosus being established in Japan, thus strict and proper meat inspection and consequent offal condemnation are requisite at abattoirs that deal with imported cattle. Genotyping based on partial fragments of mitochondrial cox1, rrnS and nad1 genes were performed on the 66 cysts, showing that most of the cysts were G1 genotype (common sheep strain). However, two and four cysts were considered as G2 (Tasmanian sheep strain) and G3 (buffalo strain) genotypes, respectively. Since it has been widely recognized that G1 is the only genotype distributing in mainland Australia and that G2 genotype has been eradicated from Tasmania, the finding of those genotypes from Australian cattle indicated that certain genotypes other than G1 genotype are distributing in mainland Australia.     

Community structure, biomass and productivity of size-fractionated summer phytoplankton populations in lower Narragansett Bay, Rhode Island

Seventeen size-fractionation experiments were carried out duringthe summer of 1979 to compare biomass and productivity in the< 10, <8 and <5 µm size fractions with that ofthe total phytoplankton community in surface waters of NarragansettBay. Flagellates and non-motile ultra-plankton passing 8 µmpolycarbonate filters dominated early summer phytoplankton populations,while diatoms and dinoflagellates retained by 10 µm nylonnetting dominated during the late summer. A significant numberof small diatoms and dinoflagellates were found in the 10–8µm size fraction. The > 10 µm size fraction accountedfor 50% of the chlorophyll a standing crop and 38% of surfaceproduction. The <8 µm fraction accounted for 39 and18% of the surface biomass and production. Production by the< 8 µm fraction exceeded half of the total communityproduction only during a mid-summer bloom of microflagellates.Mean assimilation numbers and calculated carbon doubling ratesin the <8 µm (2.8 g C g Chl a^–1 h^–1; 0.9day^–1)and<5 µm(1.7 g C g Chl a^–1h^–1; 0.5day^–1)size fractions were consistently lower than those of the totalpopulation (4.8 g C g Chl a^–1 h^–1; 1.3 day^–1)and the <10 µm size fraction (5.8 g C g Chl a^–1h^–1; 1.4 day ^–1). The results indicate that smalldiatoms and dinoflagellates in fractionated phytoplankton populationscan influence productivity out of proportion to their numbersor biomass. ¹Present address: Australian Institute of Marine Science, P.M.B.No. 3, Townsville M.S.O., Qld. 4810, Australia.     

2004年春季长江口海域甲藻孢囊的分布研究

于2004年4月初,采集长江口(E122°～123°30',N29°～32°)10个站点0～15cm底泥样品,研究甲藻孢囊在这10个站点的水平和垂直分布情况。在30个样品中共鉴定出6大类24种甲藻孢囊。孢囊组成以异养型原多甲藻类孢囊为主,有13种,平均密度为157cysts·g^-1DW,为调查海域的最优势种群。两种产麻痹性贝类毒素(Paralytic shellfish poisoning,PSP)的孢囊,塔玛亚历山大藻和链状裸甲藻,在海区分布广泛但数量较低。10个站点甲藻孢囊的种类数在11～18种之间,平均密度为189～846cysts·g^-1DW,在远离河口的D6站点有一个明显的最高峰,位于最北部的D1站点孢囊密度最低。与其它海湾相比,属于孢囊密度较低的海区。Shannon-Weaver生物多样性指数(H')变化范围在2.57～3.27之间。甲藻孢囊的密度分布与生物多样性相关系数r=-0.72。3个不同深度的甲藻孢囊密度分别为351cysts·g^-1DW、412cysts·g^-1DW、432cysts·g^-1DW;生物多样性指数分别为3.22、2.95、2.98。     

Nitrogen dynamics in lower Narragansett Bay, Rhode Island. I. Uptake by size-fractionated phytoplankton populations

The contribution of nanoplankton (< 10 µm fraction)to winter – spring (1977 – 78) and summer (1978,1979) phytoplankton nitrogen dynamics in lower NarragansettBay was estimated from ammonium, nitrate and urea uptake ratesmeasured by ¹⁵N tracer methods. During the winter – spring,an average of 80% of chlorophyll a and nitrogen uptake was associatedwith phytoplankton retained by a 10 µm screen. In contrast,means of 51 – 58% of the summer chlorophyll a standingcrops and 64 – 70% of nitrogen uptake were associatedwith cells passing a 10 µm screen. Specific uptake ratesof winter – spring nanoplankton populations were consistentlylower than those of the total population. Specific uptake ratesof fractionated and unfractionated summer populations were notsignificantly different. Ammonium uptake averaged between 50and 67% of the total nitrogen uptake for both the total populationand the < 10µm fraction. The total population and the10 µm fraction displayed similar preferences for individualnitrogen species. Though composed of smaller cells, flagellatedominated nanoplankton assemblages may not necessarily takeup nitrogen at faster rates than diatom dominated assemblagesof larger phytoplankters in natural populations. ¹Present address: Australian Institute of Marine Science, P.M.B.No. 3, Townsville M.S.O., Qld. 4810, Australia     

A Light Microscopic Comparison of The Cysts of Four Species of Sarcocystis Infecting The Domestic Reindeer (Rangifer Tarandus) in Northern Norway

Fresh preparations of micro-isolated sarcocysts from skeletal and cardiac muscle of 12 reindeer were examined by light microscopy. On the basis of cyst structure and cyst wall structure 4 Sarcocystis spp. could be differentiated. New names have been proposed for 2 previously unnamed Sarcocystis spp. of reindeer, and S. grueneri has been redefined. S. rangiferi n. sp. had macroscopic cysts in skeletal muscle measuring 2106×403 µm. The cyst wall protrusions were finger-like and measured 13.2×6.7 µm. The cysts were surrounded by a layer of fibrillar material. S. tarandi n. sp. had micro- to macroscopic cysts primarily in skeletal muscle, but a few cysts were found in the heart of one animal. In skeletal muscle the cysts measured 999×75µm; in the heart the cysts were shorter and wider. The cyst wall protrusions were fingerlike and measured 9.2×2.2 µm. S. grueneri had micro- to macroscopic cysts in cardiac muscle measuring 581×137 µm. The cyst wall was thin and relatively smooth with no visible protrusions. Sarcocystis sp. had micro- to macroscopic, slender cysts in skeletal muscle measuring 916×64 µm. The cyst wall had tightly packed, short, knob-like protrusions. The cysts of this species were previously classified as cysts of S. grueneri.