identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
50A32D8078865F32AC92846E8B398F8E.text	50A32D8078865F32AC92846E8B398F8E.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Planothidium angustirostratum Q-M. You, P. Yu & J. P. Kociolek 2025	<div><p>Planothidium angustirostratum Q-M. You, P. Yu &amp; J. P. Kociolek sp. nov.</p><p>Figs 5, 6</p><p>Holotype.</p><p>SHTU! Slide GZ 201510051, holotype illustrated in Fig. 5 F, N. Diatom samples are housed in the Lab of Algae and Environment, College of Life Sciences, Shanghai Normal University, China.</p><p>Isotype.</p><p>COLO! Material 11117, Slides are housed in the Kociolek Collection, University of Colorado, Museum of Natural History Diatom Herbarium, Boulder, U. S. A.</p><p>Type locality.</p><p>China. <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=107.75445&amp;materialsCitation.latitude=25.26" title="Search Plazi for locations around (long 107.75445/lat 25.26)">Xiaoqikong Scenic Area</a>, Libo County, Guizhou Province, 25°15'36"N, 107°45'16"E, altitude: 780 m, collected by Wang Q. X. &amp; Kociolek J. P., on October 2, 2015 .</p><p>Description.</p><p>Light microscopy (LM) (Fig. 5 A – P). Valves elliptic-lanceolate with narrowly rostrate to subcapitate apices. Valve dimensions (n = 40): Valve length 17–21 µm, width 6.5–7.0 µm. Rapheless Valve (Fig. 5 A – H): Axial area narrow, linear, slightly broadened in the middle. A horseshoe-shaped hyaline area present on one side of the central area, containing a cavum. Striae weakly radiate along the valve outline, 13–14 in 10 µm (measured opposite the hyaline area). Raphe Valve (Fig. 5 I – P): Axial area narrow, straight, linear. Central area subcircular to rectangular, bordered by 3–4 slightly shortened striae on each side. Raphe branches straight, with proximal raphe endings drop-like. Striae radiate along the valve outline, 13–14 in 10 µm.</p><p>Scanning electron microscopy (SEM) (Figs 5 Q, 6 A – C). Rapheless Valve (Figs 5 Q, 6 A): Striae composed of 3–4 rows of circular areolae, narrowing near the central area adjacent to the axial area. Striae extend onto the valve mantle. Irregular circular depressions present between the axial area, central area, even between striae. Internally, areolae covered individually, striae wider than virgae and sunken between them. Cavum opening slightly constricted. Raphe Valve (Fig. 6 B, C): Striae composed of 3–4 rows of areolae, striae near the central area regularly shortened and narrowing towards the axial area. Striae extend onto the valve mantle. Raphe branches straight, with proximal raphe endings expanding into pores surrounded by drop-like depressions. Distal raphe ends are curved in the same direction, slightly extending onto the valve mantle. Internally, proximal raphe endings slightly deflected to the opposite side, and distal raphe endings terminating in a faint helictoglossa. Internally, areolae covered individually, striae wider than virgae and sunken between them.</p><p>Etymology.</p><p>The species was named for its narrowly rostrate valve apices.</p><p>PhycoBank registration.</p><p>http://phycobank.org/105529</p><p>Distribution and ecology.</p><p>This species has currently only been found at its type locality, where it was collected from floating debris in a pond (water temperature 18.0 ° C, elevation 780 m). The species was observed only in sample (GZ 201510051) at a low relative abundance (0.75 %). In the type material, P. angustirostratum was rare. The associated diatom flora included Sellaphora sp. (15.5 %), Planothidium rostratum (12.5 %), Planothidium liboensis (5.75 %), Fallacia sp. (5.0 %), Achnanthidium minutissimum (5.0 %), Nitzschia palea (5.0 %), and other taxa with lower abundance (less than 5 %) such as Planothidium ellipticum, Sellaphora rotunda, Achnanthidium spp., Punctastriata nyingchiensis, Staurosira construens, Cocconeis placentula, and Platessa hustedtii . Additional ecological information is presented in Table 1.</p><p>Remarks.</p><p>Due to the broadly similar valve outline in LM and the presence of a cavum, Planothidium angustirostratum sp. nov. can be compared with Planothidium brasiliense Wetzel &amp; Blanco, Planothidium potapovae Wetzel &amp; Ector and Planothidium rostratoholarcticum Lange-Bertalot &amp; Bąk (Table 3). In addition to differences in striae density and valve length and width, Planothidium angustirostratum sp. nov. also can be distinguished from these similar species by the following features: (1) with narrower rostrate to subcapitate apices and a narrower cavum aperture; (2) a smaller central area, ranging from rectangular to nearly circular; (3) its striae denser on the raphe valve, consist of 3–4 rows of circular areolae; (4) circular shallow depressions are present in the central area, axial area, and between the striae, unlike the slit-like depressions observed in P. potapovae and P. rostratoholarcticum .</p><p>Note: “ Nd ” indicates no data available in the reference.</p></div>	https://treatment.plazi.org/id/50A32D8078865F32AC92846E8B398F8E	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Li, Yun;Lu, Lin-Xin;Zhou, Hui-Wen;Yu, Pan;Kociolek, John Patrick;Pang, Wan-Ting;Wang, Quan-Xi;You, Qing-Min	Li, Yun, Lu, Lin-Xin, Zhou, Hui-Wen, Yu, Pan, Kociolek, John Patrick, Pang, Wan-Ting, Wang, Quan-Xi, You, Qing-Min (2025): Four new Planothidium species (Achnanthidiaceae, Bacillariophyceae) from the Karst region of Guizhou in China. PhytoKeys 259: 81-102, DOI: 10.3897/phytokeys.259.150757
233C8D096BE25097A314A5F236BF6C22.text	233C8D096BE25097A314A5F236BF6C22.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Planothidium liboensis Q-M. You, P. Yu & J. P. Kociolek 2025	<div><p>Planothidium liboensis Q-M. You, P. Yu &amp; J. P. Kociolek sp. nov.</p><p>Figs 3, 4</p><p>Holotype.</p><p>SHTU! Slide GZ 201510051, holotype illustrated in Fig. 3 F, N. Diatom samples are housed in the Lab of Algae and Environment, College of Life Sciences, Shanghai Normal University, China.</p><p>Isotype.</p><p>COLO! Material 11117, Slides are housed in the Kociolek Collection, University of Colorado, Museum of Natural History Diatom Herbarium, Boulder, U. S. A.</p><p>Type locality.</p><p>China. Xiaoqikong Scenic Area, Libo County, Guizhou Province, 25°15'36"N, 107°45'16"E, altitude: 780 m, collected by Wang Q. X. &amp; Kociolek J. P., on October 2, 2015.</p><p>Description.</p><p>Light microscopy (LM) (Fig. 3 A – P). Valves elliptical with slightly constricted ends and rostrate extensions. Valve dimensions (n = 75): Length 12–18 µm, width 5–7 µm. Rapheless Valve (SV) (Fig. 3 A – H): Axial area narrow, straight, linear. Central area with a large, unilateral, horseshoe-shaped hyaline area containing a clearly visible cavum, on the opposite side, striae extend to the axial area. Striae radiate along the valve outline, 15–16 in 10 µm (measured opposite the cavum). Raphe Valve (RV) (Fig. 3 I – P): Axial area narrow, straight, and linear, widening slightly towards the central area. Central area irregular, rectangular to slightly rounded, bordered by 2–3 shortened, asymmetrical striae on each side. Raphe branches straight, with proximal raphe endings drop-like. Striae radiate along the valve outline, 14–17 in 10 µm.</p><p>Scanning electron microscopy (SEM) (Figs 3 Q, 4 A – C). Rapheless Valve (Figs 3 Q, 4 A): Striae composed of 4 to 5 rows of circular areolae, typically parallel to each other. Near the central area, striae often narrow to 3 areolae adjacent to the axial area. Striae extend onto the valve margin, and no areolae exist on the mantle. The axial area and central area exhibit irregular depressions. The cavum opening is broad, striae are distinctly wider than the virgae and sunken between them, areolae are covered by individual hymenes. Raphe Valve (Fig. 4 B, C): Striae composed of 4 to 5 rows of circular areolae, with some striae consisting of 3 areolae near the axial area and valve margin. Striae extend onto the valve margin, and no areolae exist on the mantle. The central area typically displays 2 to 3 shortened areolae. Raphe branches are straight, with proximal raphe endings expanding into pores, surrounded by shallow, drop-like depressions. Distal raphe ends are curved in the same direction, briefly extending onto the mantle. Internally, proximal raphe endings are slightly deflected to the opposite side, distal raphe endings terminate in a small helictoglossa. The central nodule is raised, striae are markedly wider than the virgae and sunken between them, and areolae are covered by individual hymenes.</p><p>Etymology.</p><p>The species was named for the type locality, Libo County.</p><p>PhycoBank registration.</p><p>http://phycobank.org/105528</p><p>Distribution and ecology.</p><p>This species has currently only been found at its type locality, where it was collected from rocks and floating debris in ponds, as well as from rocks beneath a waterfall (water temperature 18.0–19.5 ° C, elevation 629–780 m). The species was observed in samples GZ 201510045 (1.0 %), GZ 201510051 (5.8 %), and GZ 201510066 (1.5 %). In the type material (GZ 201510051), P. liboensis exhibited a relatively high abundance. The associated diatom flora included Sellaphora sp. (15.5 %), Planothidium rostratum (12.5 %), Fallacia sp. (5.0 %), Achnanthidium minutissimum (5.0 %), Nitzschia palea (5.0 %), and other taxa with lower abundance (less than 5 %) such as Planothidium ellipticum (Cleve) Round &amp; Bukhtiyarova, Sellaphora rotunda Wetzel, Ector, Van de Vijver, Compère &amp; Mann, Achnanthidium spp., Punctastriata nyingchiensis, Staurosira construens, Cocconeis placentula, and Platessa hustedtii . Additional ecological information is presented in Table 1.</p><p>Remarks.</p><p>In LM, P. liboensis, P. rostratum, and P. xinguense exhibit broadly similar valve outlines, and all display a cavum. However, P. liboensis can be distinguished from other taxa by the following features: (1) P. liboensis has a denser arrangement of striae, typically consisting of 4–5 rows of similarly-sized round areolae, and the striae are distinctly wider than the virgae. In contrast, the striae of P. rostratum in the rapheless valve consist of 3–4 rows of areolae, where the two middle rows are smaller than the outer rows. The striae of P. xinguense in rapheless valve are composed of 1–3 rows of areolae; (2) The central area of rapheless valve in P. liboensis exhibits distinctive irregularly shaped shallow depressions, whereas P. rostratum features shallow, slit-like depressions. P. xinguense also exhibits irregularly shaped shallow depressions in the central area, but their shape differs from those in P. liboensis . Additionally, P. xinguense has slit-like depressions in the axial area; (3) compared to P. rostratum, the cavum of P. liboensis has a more open aperture; (4) compared to P. xinguense, P. liboensis exhibits weaker striae radiation and a narrower central area on the rapheless valve.</p></div>	https://treatment.plazi.org/id/233C8D096BE25097A314A5F236BF6C22	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Li, Yun;Lu, Lin-Xin;Zhou, Hui-Wen;Yu, Pan;Kociolek, John Patrick;Pang, Wan-Ting;Wang, Quan-Xi;You, Qing-Min	Li, Yun, Lu, Lin-Xin, Zhou, Hui-Wen, Yu, Pan, Kociolek, John Patrick, Pang, Wan-Ting, Wang, Quan-Xi, You, Qing-Min (2025): Four new Planothidium species (Achnanthidiaceae, Bacillariophyceae) from the Karst region of Guizhou in China. PhytoKeys 259: 81-102, DOI: 10.3897/phytokeys.259.150757
C92B2E999C1F5D70A6AC6EF828CC24C1.text	C92B2E999C1F5D70A6AC6EF828CC24C1.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Planothidium maolanensis Q-M. You, P. Yu & J. P. Kociolek 2025	<div><p>Planothidium maolanensis Q-M. You, P. Yu &amp; J. P. Kociolek sp. nov.</p><p>Figs 7, 8</p><p>Holotype.</p><p>SHTU! Slide GZ 201510099, holotype illustrated in Fig. 7 D, L. Diatom samples are housed in the Lab of Algae and Environment, College of Life Sciences, Shanghai Normal University, China.</p><p>Isotype.</p><p>COLO! Material 11165, Slides are housed in the Kociolek Collection, University of Colorado, Museum of Natural History Diatom Herbarium, Boulder, U. S. A.</p><p>Type locality.</p><p>China. <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=108.07111&amp;materialsCitation.latitude=25.292221" title="Search Plazi for locations around (long 108.07111/lat 25.292221)">Maolan Nature Reserve</a>, Libo County, Guizhou Province, 25°17'32"N, 108°04'16"E, altitude: 650 m, collected by Kociolek J. P. &amp; Wang Q. X., on October 4, 2015 .</p><p>Description.</p><p>Light microscopy (LM) (Fig. 7 A – P). Valves elliptical, with rounded ends not extended. Valve dimensions (n = 50): Length 9.5–18.0 µm, width 5.5–7.5 µm. Rapheless Valve (Fig. 7 A – H): Axial area linear-lanceolate, with central area slightly broadened. One side of the central area has two striae with widened spacing, opposite side striae slightly shortened. Striae weakly radiate along the valve outline, narrowing towards axial area, 10–12 in 10 µm (measured opposite hyaline area). Raphe Valve (Fig. 7 I – P): Axial area linear-lanceolate, slightly widened in the central area. Central area subcircular, bordered by 2–3 slightly shortened striae on each side. One side of the central area has two striae with widened spacing. Striae radiate weakly, 10–12 in 10 µm. Raphe branches straight, occasionally slightly curved.</p><p>Scanning electron microscopy (SEM) (Figs 7 Q, 8 A – C). Rapheless Valve (Figs 7 Q, 8 A): Striae composed of 4–5 rows of circular areolae, markedly narrow near the axial area, reducing to 2–3 rows of areolae, striae almost extend onto the valve margin, and some areolae exist on the mantle. Irregular depressions present on the axial area, central area and even on the virgae. Internally, areolae covered. Virgae widen gradually from the ends towards the center, with striae sunken between virgae, a distinctly wider virgae present on one side of the central area (Fig. 8 A, White arrow). Raphe Valve (Fig. 8 B, C): Striae composed of 5–6 rows of small circular areolae, markedly narrowing near the central area, reducing to 2–3 rows of areolae. striae don’t extend onto the valve margin, and some areolae exist on the mantle (Fig. 8 B, White arrows). Raphe branches straight, occasionally slightly curved. Externally, proximal raphe endings expand into pores, distal raphe ends are curved in the same direction, and extend onto the mantle. Internally, proximal raphe endings slightly deflected to the opposite side, and distal raphe endings terminate in a small helictoglossa. Internally, areolae covered individually by membranes, striae sunken between virgae.</p><p>Etymology.</p><p>The species was named for the Maolan Nature Reserve, where the type specimen was collected.</p><p>PhycoBank registration.</p><p>http://phycobank.org/105530</p><p>Distribution and ecology.</p><p>This species has currently only been found at its type locality, where it was collected from rocks in a subsurface stream and in rapidly flowing river water (water temperature 18.0 ° C, elevation 650–811 m). The species was observed in samples GZ 201510099 (3.75 %), GZ 201510100 (0.25 %), and GZ 2015108 (0.75 %). In the type material (GZ 201510099), P. maolanensis was rare. The associated diatom flora included Cocconeis placentula (23.0 %), Achnanthidium delmontii (7.5 %), Navicula lundii (7.5 %), Navicula antonii Lange-Bertalot, Navicula sp. (6.0 %), Achnanthidium minutissimum (5.5 %), and other taxa with lower abundance (less than 5 %) such as Platessa hustedtii, Achnanthidium spp., Encyonema hophense Krammer, and Achnanthes prominula Levkov &amp; Tofilovska. Additional ecological information is presented in Table 1.</p><p>Remarks.</p><p>Due to the broadly similar valve outline in LM and the absence of cavum, Planothidium maolanensis sp. nov. can be compared with P. hauckianum (Grunow) Bukhtiyarova, P. kaetherobertianum Van de Vijber &amp; Bosak, and P. iberense Rovira &amp; Witkowski (Table 4). P. maolanensis can be easily distinguished from P. kaetherobertianum and P. iberense by valve outline and striae density, while it shows greater overall similarity to P. hauckianum . However, P. maolanensis can still be differentiated by the following features: (1) In P. maolanensis, only two striae on one side of the central area show slightly increased spacing, while the remaining striae are evenly arranged. In contrast, P. hauckianum has more striae with increased spacing on both sides of the central area. (2) The striae of P. maolanensis consist of 4–5 rows of circular areolae on rapheless valve and 5–6 rows on raphe valve. In P. hauckianum, the striae consist of 3–4 rows of circular areolae on the rapheless valve and 2–4 rows on the raphe valve. (3) Although the striae in P. maolanensis and P. hauckianum both generally narrow toward the axial area, the narrowing in P. maolanensis is not gradual or consistent. Sometimes, the middle of striae contracts, making it narrower than the ends near the axial area. (4) P. maolanensis has irregularly shaped shallow depressions in axial area and between the striae, while P. hauckianum exhibits slit-like depressions.</p></div>	https://treatment.plazi.org/id/C92B2E999C1F5D70A6AC6EF828CC24C1	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Li, Yun;Lu, Lin-Xin;Zhou, Hui-Wen;Yu, Pan;Kociolek, John Patrick;Pang, Wan-Ting;Wang, Quan-Xi;You, Qing-Min	Li, Yun, Lu, Lin-Xin, Zhou, Hui-Wen, Yu, Pan, Kociolek, John Patrick, Pang, Wan-Ting, Wang, Quan-Xi, You, Qing-Min (2025): Four new Planothidium species (Achnanthidiaceae, Bacillariophyceae) from the Karst region of Guizhou in China. PhytoKeys 259: 81-102, DOI: 10.3897/phytokeys.259.150757
09DF36F8ECAA562C80062B02ACA36692.text	09DF36F8ECAA562C80062B02ACA36692.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Planothidium pseudoreichardtii Q-M. You, P. Yu & J. P. Kociolek 2025	<div><p>Planothidium pseudoreichardtii Q-M. You, P. Yu &amp; J. P. Kociolek sp. nov.</p><p>Figs 1, 2</p><p>Holotype.</p><p>SHTU! Slide GZ 201510045, holotype illustrated in Fig. 1 C, J. Diatom samples are housed in the Lab of Algae and Environment, College of Life Sciences, Shanghai Normal University, China.</p><p>Isotype.</p><p>COLO! Material 11111, Slides are housed in the Kociolek Collection, University of Colorado, Museum of Natural History Diatom Herbarium, Boulder, U. S. A.</p><p>Type locality.</p><p>China. <a href="https://tb.plazi.org/GgServer/search?materialsCitation.longitude=107.75445&amp;materialsCitation.latitude=25.26" title="Search Plazi for locations around (long 107.75445/lat 25.26)">Xiaoqikong Scenic Area</a>, Libo County, Guizhou Province, 25°15'36"N, 107°45'16"E, altitude: 780 m, collected by Kociolek J. P. &amp; Wang Q. X., on October 2, 2015.</p><p>Description.</p><p>Light microscopy (LM) (Fig. 1 A – P). Valves elliptical with slightly constricted ends and rostrate extensions. Valve dimensions (n = 60): Length 11.5–19.0 µm, width 5.5–7.5 µm. Rapheless Valve (Fig. 1 A – H): Axial area narrow, straight, linear. Central area features a U-shaped hyaline region widening towards the valve margin, on the opposite side, striae extend to the axial area. Striae radiate along the valve outline, 14–17 in 10 µm (measured opposite hyaline area). Raphe Valve (Fig. 1 I – P): Axial area narrow, straight, linear. Central area rectangular to nearly circular, bordered by 3–4 shortened, asymmetrical striae on each side. Raphe branches straight. Striae radiate along the valve outline, 14–18 in 10 µm.</p><p>Scanning electron microscopy (SEM) (Figs 1 Q, R, 2 A, B). Rapheless Valve (Fig. 1 Q, R): Striae composed of 3–4 rows of circular areolae, the outer two rows larger than those near the center. Striae narrow to 2 rows towards the axial area and may expand to 3–4 rows near the valve margin, a larger areola marks the end of striae near the valve margin (Fig. 1 Q, white arrow). The central and axial areas feature irregular, shallow, linear depression. Internally, areolae are covered. A clearly visible sinus is present on one side of the central area, forming a shallow circular depression (Fig. 1 R, white arrow). Raphe Valve (Fig. 2 A, B): Striae composed of 3–4 rows of circular areolae. Striae narrow towards one end near the axial area. The central area typically displays 2 to 3 shortened striae. Striae almost extend onto the valve margin. Raphe branches are straight, with proximal raphe endings expanding into pores, surrounded by shallow, drop-like depressions. Distal raphe ends are curved in the same direction, briefly extending onto the mantle. Internally, proximal raphe endings are slightly deflected to the opposite side, distal raphe endings terminate in a small helictoglossa. Central nodule is raised, with striae wider raised virgae and sunken between them, and areolae are individually covered.</p><p>Etymology.</p><p>The species was named for its outline being similar to P. reichardtii .</p><p>PhycoBank registration.</p><p>http://phycobank.org/105527</p><p>Distribution and ecology.</p><p>This species has currently only been found at its type locality, where it was collected from rocks in a rapid stream (water temperature 18.0 ° C, elevation 780 m). The species was observed in sample GZ 201510041 P (2.0 %), GZ 201510045 (2.5 %). In the type material (GZ 201510045), P. pseudoreichardtii was rare. The associated diatom flora included Navicula lundii Reichardt (19.5 %), Achnanthidium delmontii Pérès, le Cohu &amp; Barthès (12.0 %), Planothidium rostratum (Østrup) Lange-Bertalot (6.0 %), Platessa hustedtii Lange-Bertalot (5.5 %), and Achnanthidium minutissimum (Kützing) Czarnecki (5.0 %), and other taxa with lower abundance (less than 5 %) such as Navicula capitatoradiata Germain, Achnanthidium rivulare Potapova &amp; Ponader, Staurosira construens Ehrenberg, Punctastriata nyingchiensis Luo &amp; Wang, Cocconeis placentula Ehrenberg, and Nitzschia palea Smith. Additional ecological information is presented in Table 1.</p><p>Remarks.</p><p>Due to their similar valve outlines, Planothidium pseudoreichardtii sp. nov. and Planothidium liboensis sp. nov. were compared with several morphologically similar taxa, including Planothidium reichardtii Lange-Bertalot &amp; Werum, Planothidium rostratum (Østrup) Lange-Bertalot and Planothidium xinguense Morais, Wetzel &amp; Bicudo (Table 2). However, P. pseudoreichardtii sp. nov. can be easily distinguished from P. liboensis sp. nov. because the former possesses a sinus, while the latter has a cavum on the center of the rapheless valve. Meanwhile, P. pseudoreichardtii can be differentiated from P. reichardtii by several distinct features: (1) in LM, the central area of the rapheless valve in P. pseudoreichardtii has a broader hyaline area outlined by 3–5 striae, whereas in P. reichardtii, the hyaline area is outlined by only 1–2 striae; (2) The striae on the rapheless valve of P. pseudoreichardtii consist of 3–4 rows of circular areolae, with the outermost two rows being larger than the central ones, whereas P. reichardtii has uniformly sized areolae in its striae; (3) the striae of P. pseudoreichardtii terminates at the valve margin with a distinctly enlarged areola, while P. reichardtii doesn’t have it. (4) irregular shallow slit-like depressions are present in the central and axial areas of the rapheless valve in P. pseudoreichardtii, whereas no depressions were observed on the rapheless valve of P. reichardtii .</p><p>Note: “ Nd ” indicates no data available in the reference.</p></div>	https://treatment.plazi.org/id/09DF36F8ECAA562C80062B02ACA36692	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Pensoft via Plazi	Li, Yun;Lu, Lin-Xin;Zhou, Hui-Wen;Yu, Pan;Kociolek, John Patrick;Pang, Wan-Ting;Wang, Quan-Xi;You, Qing-Min	Li, Yun, Lu, Lin-Xin, Zhou, Hui-Wen, Yu, Pan, Kociolek, John Patrick, Pang, Wan-Ting, Wang, Quan-Xi, You, Qing-Min (2025): Four new Planothidium species (Achnanthidiaceae, Bacillariophyceae) from the Karst region of Guizhou in China. PhytoKeys 259: 81-102, DOI: 10.3897/phytokeys.259.150757
