Plate Formula Research Articles

Biodiversity study of the genus Bysmatrum from the South China Sea and France reveals a new benthic dinoflagellate, Bysmatrum ingrilense sp. nov. (Peridiniales, Dinophyceae)

ABSTRACT The dinoflagellate genus Bysmatrum is an unusual member of the Peridiniales and cannot be attributed to any known family. Bysmatrum differs from typical peridinialean genera in that the second and third anterior intercalary plates are separated and both antapical plates are asymmetrical. Currently, Bysmatrum encompasses six epibenthic or tide-pool species, but information on their genetic diversity and biogeography remains limited. In the present study, we obtained five strains of Bysmatrum from the South China Sea by isolating single cells and three strains from Ingril, a French Mediterranean lagoon by incubating sediments. Strains from Ingril Lagoon displayed the plate formula Po, cp, X, 4′, 3a, 7′′, 6C, 4S, 5′′′, 2′′′′. They also exhibited an elongated nucleus in the hypocone and a type B eyespot. Smooth and spherical cysts were produced in culture. Small and/or partially large subunit ribosomal DNA sequences were obtained for all eight strains. Molecular phylogeny was inferred using these concatenated sequences through maximum likelihood and Bayesian inference methods. Bysmatrum granulosum and B. subsalsum were identified from Thailand and China for the first time, each of them comprising of two ribotypes. Bysmatrum ingrilense sp. nov. was monophyletic and closest to B. subsalsum ribotype B. Pinnatoxin and related toxins were examined in two strains of Bysmatrum ingrilense by LC-MS/MS, but none were detected. Our results highlight that the diversity of Bysmatrum might be underestimated.

Tributyl(hexyl)phosphonium chloride as a new leveler for microvia copper superconformal electronic plating

A phosphorus-containing new compound of tributyl(hexyl)phosphonium chloride (TBHP), but not the commonly used nitrogen-containing heterocycles and quaternary ammonium salts, is successfully applied for the superconformal copper filling of microvia in acid sulfate electroplating bath for the application of electronic industry. The molecular interaction mechanisms of TBHP combined with suppressor (polyethylene glycol, PEG) and accelerator (bis-(sodium sulfopropyl)-disulfide, SPS) are investigated in detail. Galvanostatic measurements at platinum rotation disk electrode indicate that the leveler of TBHP among with the suppressor and accelerator behaves the key characters of inhibition and convection-dependent adsorption during copper ions electroreduction for the bottom-up filling of microvia. Cyclic voltammetry measurements and in-situ FTIR spectroscopy further reveal that TBHP synergistically interacts with the suppressor to inhibit copper ions electroreduction at the mouth of microvia; while TBHP competes for adsorption with the accelerator, behaving as TBHP gradually replaced by the accelerator at the bottom. Based on the sufficient theoretical supports, the practical copper electroplating is conducted for the verification of microvia void free filling. In the developed novel copper plating formula containing TBHP, PEG and SPS, the void free filling is successfully achieved and the filling percentage (FP) is high in 95.5%.

New morphological data for two rare species of sand-dwelling marine dinoflagellates, Amphidiniella sedentaria and Pachena cf. leibnizii

Abstract Benthic dinoflagellates have been the subject of extensive taxonomic research in recent decades. Studies of morphologies of already known species of benthic dinoflagellates from various geographical populations remain relevant, as these allow elucidation of some details that were overlooked in the original species descriptions or assessment of their morphological variability. In the present study, two rare species of dinoflagellates, Amphidiniella sedentaria and Pachena cf. leibnizii, have been studied, for the first time, from coastal sands of the northwestern Sea of Japan. In the cells of A. sedentaria from the Sea of Japan, we have found two anterior intercalar plates instead of one. Therefore, the original formula has been changed to APC 4′ 2a 7″ 5c 4s 6‴ 2⁗. As a result of the examination of P. cf. leibnizii from the Sea of Japan, we have counted seven precingular plates and six cingular plates, instead of six and five, respectively, indicated in the original description. The plate formula of the cells of P. cf. leibnizii from the Sea of Japan is APC 4′ 3a 7″ 6c 5s 5‴ 2⁗. It is currently difficult to judge whether these differences are morphological variations. Therefore, we have identified these cells as P. cf. leibnizii.

Spatial fragmentation in the distribution of diatom endosymbionts from the taxonomically clarified dinophyte Kryptoperidinium triquetrum (= Kryptoperidinium foliaceum, Peridiniales)

Among the photosynthetically active dinophytes, the Kryptoperidiniaceae are unique in having a diatom as endosymbiont instead of the widely present peridinin chloroplast. Phylogenetically, it is unresolved at present how the endosymbionts are inherited, and the taxonomic identities of two iconic dinophyte names, Kryptoperidinium foliaceum and Kryptoperidinium triquetrum, are also unclear. Multiple strains were newly established from the type locality in the German Baltic Sea off Wismar and inspected using microscopy as well as molecular sequence diagnostics of both host and endosymbiont. All strains were bi-nucleate, shared the same plate formula (i.e., po, X, 4′, 2a, 7′′, 5c, 7s, 5′′′, 2′′′′) and exhibited a narrow and characteristically L-shaped precingular plate 7′′. Within the molecular phylogeny of Bacillariaceae, endosymbionts were scattered over the tree in a highly polyphyletic pattern, even if they were gained from different strains of a single species, namely K. triquetrum. Notably, endosymbionts from the Baltic Sea show molecular sequences distinct from the Atlantic and the Mediterranean Sea, which is the first report of such a spatial fragmentation in a planktonic species of dinophytes. The two names K. foliaceum and K. triquetrum are taxonomically clarified by epitypification, with K. triquetrum having priority over its synonym K. foliaceum. Our study underlines the need of stable taxonomy for central questions in evolutionary biology.

Improving the Accuracy of Seafloor Topography Inversion Based on a Variable Density and Topography Constraint Combined Modification Method

The use of satellite altimetry to recover marine gravity anomalies allows for the rapid acquisition of seafloor topography on a wide range of regional scales. Currently, the commonly used approaches for inverting seafloor topography have been focused on the linear correlation between gravity anomalies and seafloor topography and have disregarded the effect of density contrast between the crust and seawater on depth. Therefore, we proposed a variable density and topography constraint combined modification (VDTCCM) method by deriving Parker’s formula and the Bouguer plate formula by introducing variable density and topography factors. This method can effectively recover topography-related nonlinear terms of gravity anomalies. Subsequently, the seafloor topography of the South China Sea was estimated by applying the VDTCCM method and was defined as Seafloor topography one (ST1), and following, the accuracy was evaluated using shipborne sounding data (SSD). The results indicate that the ST1 model’s SSD-checked accuracy is 23.34% and 39.42% higher than the common international models of ETOPO1 and DTU10, respectively. Moreover, the ST1 model has advantages in mapping rugged areas, showing more detailed topographical features. Consequently, the VDTCCM method can provide beneficial references for the construction of seafloor topography models on a large regional scale using gravity anomalies recovered from satellite altimetry.

A Variational Derivation of Stoney-Like Formulas for Self-Stressed Bilayered Plates

Since the beginning of the 20th century, it is known that the spontaneous bending of heterogeneous bilayered plates correlates with the self-stress due to the contrast in the material properties of the two layers, and that this correlation can be exploited to gauge the internal stress state. Over the last decades, ever-growing device miniaturization has made stress assessment and even stress engineering an area of major technological interest. In this paper, we obtain two effective 2D models accounting for the spontaneous bending of devices comprised of a thin substrate and a much thinner coating by applying a $\varGamma $ -convergence technique to the standard 3D linear hyperelastic model of a bilayered plate. Our procedure is characterized by the introduction of two distinct smallness parameters plus three independent energy scaling parameters.

Gonyaulax geomunensis sp. nov. and two allied species (Gonyaulacales, Dinophyceae) from Korean coastal waters and East China Sea: morphology, phylogeny and growth response to changes in temperature and salinity

ABSTRACT Six strains of three different Gonyaulax species were established by isolating cells from the Korean coastal area and the East China Sea, and their morphologies and molecular phylogenies based on SSU and LSU rRNA gene sequences were examined. In addition, the growth responses of the Gonyaulax species to changes in temperature and salinity were investigated. Based on morphological features and phylogenetic positions, Gonyaulax whaseongensis and G. polygramma were identified, and G. geomunensis sp. nov. is proposed in this study. These species displayed the plate formula typical for Gonyaulax, but G. polygramma and G. geomunensis sometimes showed a small intercalary plate (1a) surrounded by plates 2’, *3’ and 3’’. G. geomunensis was morphologically characterized by an S-type ventral organization, descending with a displacement of one cingulum width and bearing one, two or three prominent antapical spines of similar size. The cell surface, which was distinct from other Gonyaulax species, was thick and heavily reticulated into numerous polygonal areas. The reticulation was deeply excavated. The phylogenetics revealed that G. geomunensis and G. whaseongensis belong to different clades, and that there are two ribotypes of G. polygramma, which were morphologically indistinguishable. These species had a close phylogenetic relationship to G. hyalina, and all of them were characterized by dextral torsion. G. whaseongensis, G. polygramma and G. geomunensis had different growth responses to changes of temperature and salinity, respectively, indicating that morphological and phylogenetic identification of Gonyaulax species can be supported by ecological niches.

Pentaplacodinium lapazense sp. nov. from Central and Southern Gulf of California, a new non-toxic gonyaulacalean resembling Protoceratium reticulatum

A new Pentaplacodinium species with six precingular plates is described from Bahía Concepción and Bahía de la Paz, Gulf of California. The non-fossil motile stage is described as Pentaplacodinium lapazense, whilst the fossil stage is described as Operculodinium lapazense. The cyst morphology is compared to topotype material of Operculodinium israelianum, which is larger, has longer processes and has a different wall structure. The motile cells display a plate formula of Po, Pt, X, 2′+*2′, 6′′, 6c, 7s, 5′′′, 1p, 1′′′′. A typical gonyaulacalean fission line and plate overlap are observed. SSU-ITS-LSU ribosomal DNA sequences demonstrate that Pentaplacodinium saltonense is its closest relative. The species is homothallic. This species occurs in relatively shallow and restricted coastal areas, and has a preference for higher sea-surface temperatures and salinities. Micro-FTIR spectra of the cysts are compared to spectra of cysts of other gonyaulacaleans and suggest very similar compositions. No yessotoxins were detected in any of the analyzed strains, hence, this species is unlikely to be responsible for the elevated yessotoxin concentration observed in shellfish on the southern and central coastal region of the Gulf of California.

Morphology and molecular phylogeny of the benthic dinoflagellates (Dinophyceae, Peridiniales) Amphidiniopsis crumena n. sp. and Amphidiniopsis nileribanjensis n. sp.

Amphidiniopsis is a benthic, heterotrophic and thecate dinoflagellate genus that has a smaller epitheca and larger hypotheca. The genus contains 24 described species, but is considered to be polyphyletic based on morphological characters and molecular phylogenetics. In this study, two new species were discovered from two distant sampling localities, Amphidiniopsis crumena sp. nov. from Japan, and Amphidiniopsis nileribanjensis sp. nov., from Australia. These species have a uniquely shaped, additional second postcingular plate. Both species are dorsoventrally flattened, an apical hook is present, and have six postcingular plates. The plate formula is: APC 4′ 3a 7″ ?C 4?S 6″′ 2″″. The cells of these species were examined with LM and SEM, and molecular phylogenic analyses were performed using 18S and 28S rDNA. These species are distinguished by the presence of spines on the hypotheca and touching of the sixth postcingular plate and the anterior sulcal plate. Their shape and disposition of several thecal plates also differ. Molecular phylogenetic analyses showed that the two new species formed a monophyletic clade and did not belong to any morphogroup proposed by previous studies. Considering the morphological features and the molecular phylogenetic results, a new morphogroup is proposed, Amphidiniopsis morphogroup VI (‘crumena group’).

Morphology of the marine, planktonic, thecate dinoflagellate Gonyaulax areolata (Dinophyceae), a species causing red tides in the tropical Mexican Pacific

ABSTRACT Blooms of marine planktonic dinoflagellates are usual along the Pacific coast of Mexico, sometimes producing toxic red tides. The thecate dinoflagellate Gonyaulax areolata was found to produce a red tide event in the tropical Mexican Pacific. The species was originally described in 1911 by Kofoid and Michener without an illustration. The morphology of G. areolata was studied here by LM and SEM. Photosynthetic, solitary cells were fairly small, polyhedral, with a short apical protrusion and ‘shoulders’ on the epitheca, and two short, asymmetrical antapical spines. The cingulum was approximately median, cavozone, with the ends fairly displaced but with no, or only slight, overhang. The thecae were strongly ornamented with striae, areolae and pores. The plate formula was Po, 4ʹ, Q, 6ʹʹ, 6c, 4s, 6ʹʹʹ, 1p, 1ʹʹʹʹ, as recently attributed to some species of Gonyaulax. Details of important plates are given. Gonyaulax areolata seems to be morphologically closely related to other small species with a slight cingulum displacement and overhang, such as G. minima and G. striata, and more distantly related to G. spinifera. The maximum concentration of G. areolata was 1.74 × 106 cells l–1, in association with lower numbers of other dinoflagellates and diatoms. Yessotoxins were not detected. Oceanographic conditions during the bloom indicated moderate to weak upwelling, confirmed by both relatively low surface temperature and high Chl a concentration (14 µg l–1).

Inhibition of multi-site adsorption of polyethylene glycol during copper via-filling process

The inhibitory effect of molecular weight (Mw) of polyethylene glycol (PEG) on the through-hole filling by copper electroplating was investigated by the electrochemical testing method and energy change with DFT. The cathodic polarization, electron transfer resistance, and diffusion coefficient of PEG with different Mw and concentration were assayed by cyclic voltammetry and electrochemical impedance spectroscopy; The inhibitory effect of different PEG Mw was demonstrated and examined by cross-sectional images using OLYMPUS confocal laser microscope, and the thickness of the copper layer and TP value were important measurement standards. The adsorption behavior on copper surfaces was calculated using the first principles. As PEG Mw and concentration are increased, the best TP value and diffusion coefficient of the plating formula is gained when PEG Mw and concentration are 20000 g/mol and 250 mg/L, they are 148.56% and 2.34 × 10-7, respectively. Better adsorption energy can be obtained as the adsorption sites of PEG increases, and the adsorption energy of PEG5 is − 1.99 eV. The experimental and theoretical results show that PEG with small Mw has no inhibitory effect, and even accelerates the deposition rate of Cu2+/1+. Only when the Mw and concentration exceed 2000 g/mol and 150 mg/L, PEG can inhibit the deposition of Cu2+/1+, and the best effect of through-hole electroplating is 20000 g/mol and 250 mg/L.

Rediscovery of the gonyaulacoid dinoflagellate Schuettiella.

The Gonyaulacales includes some of the most intensely investigated genera of harmful dinoflagellates. The knowledge of the evolutionary relationships is necessary, but incomplete because genera such as Schuettiella have not been studied by contemporary methods. The morphology and molecular phylogeny of type species of the genus Schuettiella, S.mitra, have been investigated from Brazil. The first scanning electron micrographs reveal a distinctive thecal ornamentation with sunken stripes and rows with exclamation mark-shaped pores in the postcingular plates. The Kofoidean plate formula Po, 2', 1a, 6″ is re-interpreted as Po, 3', 1a, 5″, after considering the narrow mid-ventral plate as homologous to the first apical plate, although it does not reach the apex. In the rRNA gene phylogenies, the sequences of S.mitra clustered as an independent lineage closely related to the globular and planktonic Protoceratiaceae (Ceratocorys, Pentaplacodinium, Protoceratium) and the laterally compressed benthic genus Carinadinium (formerly Thecadinium). Schuettiella and Carinadinium are considered members of the Protoceratiaceae. The possession of a single anterior intercalary plate is an apomorphic trait of this family. This reinforces the value of the number of intercalary plates as a diagnostic character for the classification of the gonyaulacalean families despite the differences in the general appearance.

Gonyaulacalean tabulation revisited using plate homology and plate overlap, with emphasis on the ventral area (Dinophyceae)

ABSTRACT We propose a standardization of the gonyaulacalean (Dinophyceae) Kofoidian plate tabulation using plate homology and overlap patterns, on the basis of a new morphological study of species belonging to 17 genera previously classified in the order Gonyaulacales: Acanthogonyaulax, Alexandrium, Amphidoma, Azadinium, Ceratium, Ceratocorys, Cladopyxis, Cribroperidinium, Fragilidium, Gonyaulax, Heterodinium, Lingulodinium, Paleophalacroma, Peridiniella, Spiraulax, Triadinium and Tripos. The plate immediately left of the flagellar pore is reinterpreted as a sulcal plate rather than its more conventional interpretation as a postcingular plate. With this new perspective the studied genera fall into two groups: 1) genera with only five Kofoidian postcingular plates (Acanthogonyaulax, Alexandrium, Ceratocorys, Cribroperidinium, Gonyaulax, Lingulodinium, Spiraulax and Triadinium) or six postcingular plates (Fragilidium); 2) genera with six Kofoidian postcingular plates, as well as differences in episomal plate patterns (Amphidoma, Azadinium, Cladopyxis, Heterodinium, Paleophalacroma and Peridiniella). The former are here considered true gonyaulacaleans, whilst the latter need further study for a more appropriate phylogenetic placement, and are here informally called non-gonyaulacaleans. In these non-gonyaulacalean genera, the first posterior intercalary plate overlaps the first postcingular plate/anterior left sulcal plate, but is always overlapped by the second postcingular homologue plate (a plate in similar position) demonstrating that the first plate of the postcingular series is not homologous in the two groups. Additionally, the identical overlapping pattern shows that the anterior left sulcal plate (Ssa) in gonyaulacaleans with five postcingular plates is the same plate as the first postcingular plate in gonyaulacaleans with six postcingular plates. Kofoidian definitions of posterior intercalary plates as well as antapical plates remain the same and are applied here. The Kofoidian hyposomal plate formula for gonyaulacaleans would then be 5–6''', 2p, 1''''.

A new potentially toxic dinoflagellate Fukuyoa koreansis sp. nov. (Gonyaulacales, Dinophyceae) from Korean coastal waters: Morphology, phylogeny, and effects of temperature and salinity on growth

To clarify an unspecified toxic Gambierdiscus-like species isolated from seawaters off Jeju Island, Korea, its morphology and molecular phylogeny based on the small subunit (SSU) and partial large subunit (LSU) rRNA gene sequences were examined. Cells were narrow in ventral view and broad in lateral view with a smooth surface. The round thecal pores were evenly distributed, with an average diameter of 0.41 µm. Cell depth, width and height were 51.7 ± 4.5 μm, 43.0 ± 4.2 μm and 55.0 ± 4.7 μm, respectively, and depth-to-width (D/W) and height-to-width (H/W) ratios were 1.1 ± 0.2 μm and 1.3 ± 0.02 μm, respectively. The nucleus was located in the hypotheca. Scanning electron microscope observations revealed that the cells displayed a plate formula of Po, 4′, 6′′, 6c, 6s, 5′′′ and 2′′′, and transmission electron microscope observation demonstrated that the cells contained crystal-like particles. Morphological features indicated that the unspecified Korean isolate belonged to the genus Fukuyoa, and based on the H/W and D/W ratios, the apical pore H/W ratio and thecal pore size, it could be differentiated from other Fukuyoa species. The phylogenetic analyses based on the SSU and LSU rRNA sequences revealed that the Korean isolate was nested within the genus Fukuyoa with high support, and it grouped with F. cf. yasumotoi isolated from Japan. Based on the morpho-molecular data, a new species, Fukuyoa koreansis sp. nov. is proposed. The maximum growth rate (0.254 d−1) of F. koreansis was observed at 25°C and a salinity of 25. The required levels of temperature and salinity for growth distinguished Fukuyoa koreansis from Gambierdiscus species.

Effects of additives on via filling and pattern plating with simultaneous electroplating

PurposeThe purpose of this paper is to solve the issue of via filling and pattern plating simultaneously by concentration optimization of accelerator and leveler in the electroplating bath.Design/methodology/approachThis paper designs a series of experiments to verify the performance of pattern plating with the via filling plating formula. Then the compositions of electroplating solution are optimized to achieve via filling and pattern plating simultaneously. Finally, the mechanism of co-plating for via and line is discussed in brief.FindingsTo achieve excellent performance for via filling and pattern plating simultaneously, proportion of additives are comprehensively considered in optimization of electroplating process. Effects of additives on the via filling and pattern plating should be taken into consideration, especially in achieving flat lines.Originality/valueThis paper discusses the different effects of accelerator and leveler on the via filling and the pattern plating, respectively. The process of co-plating for the via and the line is presented. The superfilling of via and the flat line are simultaneously obtained with the optimized via filling formula.

Fensomea setacea, gen. & sp. nov. (Cladopyxidaceae, Dinophyceae), is neither gonyaulacoid nor peridinioid as inferred from morphological and molecular data

Dinophyte evolution is essentially inferred from the pattern of thecal plates, and two different labelling systems are used for the important subgroups Gonyaulacales and Peridiniales. The partiform hypotheca of cladopyxidoid dinophytes fits into the morphological concepts of neither group, although they are assigned to the Gonyaulacales. Here, we describe the thecate dinophyte Fensomea setacea, gen. & sp. nov., which has a cladopyxidoid tabulation. The cells displayed a Kofoidean plate formula APC, 3′, 4a, 7″, 7C, 6S, 6′′′, 2′′′′, and slender processes were randomly distributed over the echinate or baculate surface. In addition, we obtained rRNA sequences of F. setacea, gen. & sp. nov., but dinophytes that exhibit a partiform hypotheca did not show a close relationship to Gonyaulacales. Character evolution of thecate dinophytes may have progressed from the ancestral state of six postcingular plates, and two more or less symmetrically arranged antapical plates, towards patterns of only five postcingular plates (Peridiniales) or more asymmetrical configurations (Gonyaulacales). Based on our phylogenetic reconsiderations the contact between the posterior sulcal plate and the first postcingular plate, as well as the contact between an antapical plate and the distalmost postcingular plate, do not represent a rare, specialized gonyaulacoid plate configuration (i.e., the partiform hypotheca of cladopyxidoid dinophytes). Instead, these contacts correspond to the common and regular configuration of peridinioid (and other) dinophytes.

First Report of the Marine Benthic Dinoflagellate Bysmatrum subsalsum from Korean Tidal Pools

Dense patches were observed in the tidal pools of the southern area of Korea. To clarify the causative organisms, the cells were collected and their morphological features were examined using light and scanning electron microscopy (SEM). In addition, after establishing strains for the cells the molecular phylogeny was inferred with concatenated small subunit (SSU) and large subunit (LSU) rRNA sequences. The cells were characterized by a nucleus in the hypotheca, strong reticulations in thecal plates, the separation of plates 2a and 3a, the tear-shaped apical pore complex, an elongated rectangular 1a plate and the absence of the right sulcal list. The thecal plate formula was Po, X, 4′, 3a, 7″, 6c, 4S, 5′′′, 2′′′′. Based on these morphological features, the cells were identified as Bysmatrum subsalsum. In the culture, the spherical cysts of B. subsalsum without thecal plates were observed. Molecular phylogeny revealed two ribotypes of B. subsalsum are identified; The Korean isolates were nested within the ribotype B consisting of the isolates from China, Malaysia and the French Atlantic, whereas the ribotype A includes only the isolates from the Mediterranean Sea. In the phylogeny, B. subsalsum and B. austrafrum were grouped. This can be supported by the morphological similarity between the two species, indicating that the two species may be conspecific, however B. subsalsum may distinguish from B. austrafrum, because of differences in the types of eyespots reported in previous studies. These findings support the idea that there is cryptic diversity within B. subsalsum.

A morphological comparison of two cladopyxidacean dinoflagellates: the extant Micracanthodinium setiferum and the fossil Cladopyxidium saeptum (Dinophyceae, Gonyaulacales)

Among dinoflagellates, extant cladopyxidaceans may provide a missing link to better understand the first evolutionary transformations from ancestral configurations toward the more abundant and more derived patterns in Gonyaulacales and Peridiniales. A restudy of the extant, motile-defined Micracanthodinium setiferum using plankton samples from the Indian and Atlantic oceans and the Mediterranean Sea demonstrates that the correct plate formula is Po, Pt, X, 3′ + *4′, 4a, 7′′, 7C, 4S, ?6′′′, 0p, 2′′′′. A ventral pore is found between 1′, 3′ and *4′. A restudy of the extinct, fossil-defined Cladopyxidium saeptum from the upper Paleocene of Delaware (USA), demonstrated the presence of an identical tabulation. A ventral pore (= porichnion) was positioned between *1′ and 7′′. Cladopyxidium is morphologically closer to Micracanthodinium than to Cladopyxis. Since Cladopyxidium has been extinct since the middle Eocene, it is unlikely that Micracanthodinium and Cladopyxidium have a direct biological link; the close morphological similarity between them does, however, suggest an important phylogenetic relationship between them in the evolution of cladopyxidaceans.

Recommendations for epitypification of dinophytes exemplified by Lingulodinium polyedra and molecular phylogenetics of the Gonyaulacales based on curated rRNA sequence data

Gonyaulacales include a considerable number of harmful algae and to understand their origin and rise, knowledge of the evolutionary relationships is necessary. Many scientific names of protists introduced prior to the availability of DNA analytics are ambiguous and impede communication about biological species and their traits in the microbial world. Strains of Lingulodinium polyedra were established from its type locality in the Kiel Fjord (Germany) to clarify its taxonomy. Moreover, the phylogeny of Gonyaulacales was inferred based on 329 rRNA sequence accessions compiled in a curated sequence data base, with as much as possible type material equivalents included. Gonyaulacales were monophyletic and segregated into seven lineages at high systematic level, of which †Lingulodiniaceae constituted the first branch of the Gonyaulacales. Their type species had a plate formula APC (Po, X, cp), 3′, 3a, 6′′ 6c, 6s, 6′′′, 2′′′′ and is taxonomically clarified by epitypification. Recommendations for this important taxonomic tool are provided, with a focus on microorganisms. Most gonyaulacalean taxa established at generic rank are monophyletic, with Alexandrium, Coolia and Gonyaulax as notable exceptions. From an evolutionary perspective, gonyaulacalean dinophytes with quinqueform hypotheca are monophyletic and derive from a paraphyletic group showing the sexiform configuration.

Morphology and Phylogeny of Scrippsiella precaria Montresor & Zingone (Thoracosphaerales, Dinophyceae) from Korean Coastal Waters

The dinoflagellate genus Scrippsiella is a common member of phytoplankton and their cysts are also frequently reported in coastal sediments worldwide. However, the diversity of Scrippsiella in Korean waters has not been fully investigated. Here, several isolates of Scrippsiella precaria collected from Korean waters and germinated from resting cysts were examined using light and scanning electron microscopy. The resting cysts were characterized by pointed calcareous spines and one or two red accumulation bodies, and the archeopyle was mesoepicystal, representing the loss of 2–4′ and 1–3a paraplates. Rounded resting cysts were found in culture, and an increase in spine length was observed until 8 days of development. Korean isolates of S. precaria had the plate formula of Po, X, 4′, 3a, 7″, 6C, 4S, 5‴, 2⁗. There were differences in the cell size and location of the red body between Korean isolates and previously described cells of S. precaria. In addition, the Korean isolates of S. precaria had two types of the 5″ plate that either contacted the 2a plate or not. Molecular phylogeny based on internal transcribed spacer (ITS) and large subunit (LSU) rDNA sequences revealed that the Korean isolates were nested within the subclade of PRE (S. precaria and related species) in the clade of Scrippsiella sensu lato, and that the PRE subclade had two ribotypes: ribotype 1 consisting of the isolates from Korea, China, and Australia, and ribotype 2 consisting of the isolates from Italy and Greece. Lineages between isolates of ribotype 1 were likely to be related to the dispersal by ocean currents and ballast waters from international shipping, and the two types of spine shapes and locations of the 5″ plates may be a distinct feature for ribotype 1.