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FIGURES 10–18 in Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new
No full textFIGURES 10–18: Cyclotella kansasica. LM. Valve views showing flat valve face and size diminution series. Scale bars = 5 µm.Published as part of Kociolek, J. P. & Khursevich, G. K., 2013, Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new, pp. 81-99 in Phytotaxa 127 (1) on page 85, DOI: 10.11646/phytotaxa.127.1.11, http://zenodo.org/record/508551
FIGURES 70–71 in Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new
No full textFIGURES 70–71: Cyclotella jonesii. LM. Figure 70 is of Morphotype 1. Figure 71 is of Morphotype 2. Scale bars = 10 µm.Published as part of Kociolek, J. P. & Khursevich, G. K., 2013, Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new, pp. 81-99 in Phytotaxa 127 (1) on page 95, DOI: 10.11646/phytotaxa.127.1.11, http://zenodo.org/record/508551
Valve morphology of three species of Neidiomorpha (Bacillariophyceae) from Zoigê Wetland, China, including description of Neidiomorpha sichuaniana nov. sp.
No full textLiu, Qi, Kociolek, J. P., Wang, Quanxi, Fu, Chengxin (2014): Valve morphology of three species of Neidiomorpha (Bacillariophyceae) from Zoigê Wetland, China, including description of Neidiomorpha sichuaniana nov. sp. Phytotaxa 166 (2): 123-131, DOI: 10.11646/phytotaxa.166.2.3, URL: http://dx.doi.org/10.11646/phytotaxa.166.2.
FIGURES 6–9 in Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new
No full textFIGURES 6–9: Cyclotella idahica. SEM. Figures 6, 7, 9. external views. Valve views showing transversely undulate central area with irregularly arranged areolae and covered by bumps. Present are external openings of areolae and short tubes of marginal fultoportulae. Spines and/or spines bases are found on the valve face/mantle junction. Scale bars = 1 µm. Figure 8, internal view. Valve view showing location of one fultoportula on the valve face. Arrow indicates position of the rimportula. Scale bar = 1 µm.Published as part of Kociolek, J. P. & Khursevich, G. K., 2013, Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new, pp. 81-99 in Phytotaxa 127 (1) on page 84, DOI: 10.11646/phytotaxa.127.1.11, http://zenodo.org/record/508551
FIGURES 32–37 in Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new
No full textFIGURES 32–37: Cyclotella discostelliformica. SEM. Figures 32, 33. External views showing valves with sunken and elevated central areas, respectively. Fascicles are composed of 2–5 rows of areolae. Openings of the marginal fultoportulae are located at or near the thickened ribs. They lack tubes or thickenings. The central portion of the valves have isolated areolae, that are larger than those of the fascicles. Scale bars = 1 µm. Figures 34–37. Internal valve views showing a single central fultoportula with 3 satellite pores, and marginal fultoportulae at every costa or every second costa. The rimoportula is located on or near a costa (arrows). Scale bars = 1 µm.Published as part of Kociolek, J. P. & Khursevich, G. K., 2013, Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new, pp. 81-99 in Phytotaxa 127 (1) on page 88, DOI: 10.11646/phytotaxa.127.1.11, http://zenodo.org/record/508551
FIGURES 19–24 in Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new
No full textFIGURES 19–24: Cyclotella kansasica, SEM. Figures 19–21, external views. Flat valve face has striae with 3–4 rows of areolae towards the margin, and scattered areolae in the center, usually with one enlarged depression. Openings of the marginal fultoportulae occur on every rib. Thick spines or bases are visible on the margin of the valve. Scale bars = 1 µm. Figures 22–24, internal views. Marginal fultoportulae occur on every costa. A ring of simple alveolae is present on the mantle. Central fultoportulae are wanting. Central areolae do not reflect an enlarged opening seen externally. Scale bars = 1 µm.Published as part of Kociolek, J. P. & Khursevich, G. K., 2013, Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new, pp. 81-99 in Phytotaxa 127 (1) on page 86, DOI: 10.11646/phytotaxa.127.1.11, http://zenodo.org/record/508551
FIGURES 29–33 in Valve morphology of three species of Neidiomorpha (Bacillariophyceae) from Zoigê Wetland, China, including description of Neidiomorpha sichuaniana nov. sp.
No full textFIGURES 29–33. SEM micrographs of Neidiomorpha binodiformis. Fig. 29. External view of the valve. Fig. 30. Valve terminus showing distal raphe end. Fig. 31. External view of central valve face, with large areolae on the mantle. Fig. 32. Internal view of the valve, distal valve showing helictoglossae and inside pluriseriate areolation pattern over the shallow cave. Fig. 33. Internal view of central valve showing the central nodule. Scale bars = 5µm (Fig. 29); 1µm (Figs 30–33).Published as part of Liu, Qi, Kociolek, J. P., Wang, Quanxi & Fu, Chengxin, 2014, Valve morphology of three species of Neidiomorpha (Bacillariophyceae) from Zoigê Wetland, China, including description of Neidiomorpha sichuaniana nov. sp., pp. 123-131 in Phytotaxa 166 (2) on page 129, DOI: 10.11646/phytotaxa.166.2.3, http://zenodo.org/record/513829
Cyclotella kansasica Hanna 1932
No full textCyclotella kansasica Hanna (1932: 376) (Figs 10–24) Hanna 1932. University of Kansas Science Bulletin 20: 376, pl. 31, fig. 6. Material examined: — USA. Kansas: Wallace County, Diatom marl from center Sec. 11, T.11S., R 38W, Marshall ranch, North Fork Smoky Hill River, Ogallala Formation. CAS Accession Number 2383 (CAS!). This is the type material studied by Hanna (1932). USA. Kansas: Wallace County, Sec. 12, T.11S., R 38W. CAS Accession Number 604437, Slide numbers 423092, 423093 (CAS!). Description: —Valves are circular, nearly flat, 4.5–16.5 µm in diameter, with several girdle bands and a well-defined border between the central area and the marginal alveolate zone. Central area with one more or less well-developed depression at the center and a variable number of areolae which are arranged irregularly or in short radial rows. Marginal zone extending a little over 1/3 of the valve radius consists of alveolate striae fascicles, 8–12 in 10 µm, separated by hyaline interfascicles. Striae fascicles are of equal length. They contain 3–4 rows of puncta, 40–60 in 10 µm. Alveoli are simple. Length of alveolar openings is almost equal to the length of striae fascicles. Marginal fultoportulae with 3 satellite pores are located on every costa or every second costa separating alveolar openings internally. A single rimoportula occurs at the marginal ends of one of the costae. Spines are present at the junction of the valve face and mantle at every interfascicle, but they may be broken.Published as part of Kociolek, J. P. & Khursevich, G. K., 2013, Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new, pp. 81-99 in Phytotaxa 127 (1) on page 85, DOI: 10.11646/phytotaxa.127.1.11, http://zenodo.org/record/508551
Grunowia mannii Kociolek & A. Danz 2022, sp. nov.
No full textGrunowia mannii Kociolek & Danz, sp. nov., Figures 1–15. Description:— Valves narrowly cruciform, with apical axis very narrow and apices narrow, round; the center with rounded margins. Length 5 – 16 µm, breadth 2 – 6 µm. Keel distinct, placed at or near the center of the valve. Fibulae 8 – 10/10 µm. Striae fine, appearing as lines (without visible puncta), parallel, 18 – 23 / 10 µm. Number of specimens measured = 100. In the SEM, the valve exterior has a narrow, raised keel positioned just off-center in larger (Figs 8, 9) specimens but closer to the margin in smaller specimens. Striae are composed of round areolae, 40 – 50 in 10 µm within a stria. Striae are parallel with a density of 20 – 25 in 10 µm. Number of specimens measured = 10. The raphe is positioned in the keel, and has two distinct branches (Figs 8, 11). External distal raphe ends are bent slightly and curved onto the narrow mantle (Fig. 10). External proximal raphe ends terminate close to one another and are straight (Fig. 11). Internally, the raphe is contained in a canal, with portules of varying sizes (Figs 12 – 14). Fibulae are relatively wide for the size of the valves. The proximal raphe ends terminate at a small central nodule that appears similar to helictoglossae (Fig. 15). Type:— USA, Rio Arriba County, New Mexico, Chamita Formation, USGS Diatom Locality 4672, holotype COLO! Slide # 278018 in the J.P. Kociolek Diatom Collection at the University of Colorado, Boulder = Fig. 4; isotype: ANSP! Slide #GC 65441 in the Academy of Natural Sciences of Drexel University. Etymology:— Named for the diatomist Dr. David Mann, for all of his efforts to uncover and resolve the riddles contained within the Bacillariales. Comments:— This delicate species was well-preserved in the ca. 9 million year-old sediments of the Esmeralda Formation.Published as part of Kociolek, J. P. & Danz, A., 2022, Taxonomy and valve ultrastructure of new and interesting freshwater fossil diatoms (Bacillariophyta) of Miocene age from the Espanola Formation of New Mexico, U. S. A. II. Description of a New Grunowia species with comments on the genus, pp. 295-300 in Phytotaxa 530 (3) on page 298, DOI: 10.11646/phytotaxa.530.3.5, http://zenodo.org/record/583600
Cyclotella pseudokansasica Khursevich & Kociolek 2013, sp. nov.
No full text<i>Cyclotella pseudokansasica</i> Khursevich & Kociolek, <i>sp. nov.</i> (Figs 56–69) <p> <b>Type:—</b> USA. Idaho: Owyhee County, Chalk Hills Formation, USGS Diatom Locality 5244, (Circled specimen (Fig. 61) on <i>CAS Slide #381069</i>, material <i>CAS Accession Number 602190</i> (CAS!), <b>holotype, designated here</b>).</p> <p> <b>Description:</b> —Valves are circular, nearly flat, 10–23 µm in diameter, with a well-defined border between the central area and the marginal alveolate zone. Central area with a variable number of irregularly arranged areolae. Marginal zone extending from 1/3 to 1/2 of the valve radius consists of alveolate striae fascicles, 8– 12(14) in 10 µm, separated by hyaline interfascicles or costae. Striae fascicles are of equal length. They contain 3–4 rows of puncta, 40–60 in 10 µm. Alveoli are simple. Length of alveolar openings is not equal to the length of striae fascicles. Marginal fultoportulae with 3 satellite pores are located on every second–fourth costa separating alveolar openings internally. A single rimoportula occurs at one of the costae. Spines are present at the junction of the valve face and mantle at every interfascicle or costa.</p> <p> <b>Remarks:</b> — <i>Cyclotella pseudokansasica</i> is similar to <i>C. kansasica</i> in the structure of alveolae, in the location of rimoportula and marginal fultoportulae, but differs by the absence of one more or less welldeveloped depression at the center, as well as by the shorter length of alveolar openings as compared with the length of striae fascicles.</p>Published as part of <i>Kociolek, J. P. & Khursevich, G. K., 2013, Morphology of some fossil lacustrine centric species from the western United States assigned to the genus Cyclotella (Bacillariophyta), including four described as new, pp. 81-99 in Phytotaxa 127 (1)</i> on pages 93-94, DOI: 10.11646/phytotaxa.127.1.11, <a href="http://zenodo.org/record/5085519">http://zenodo.org/record/5085519</a>
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