taxonID	type	description	language	source
03A38797FF84622D8CD9AE9CFCF4ED51.taxon	materials_examined	Holotype. Slide no. kam 197, in the collection of Maxim Kulikovskiy, Institute of Plant Physiology, Russian Academy of Sciences, Russia, represented here by Figure 3. Reference strain. kam 197 (08029), isolated from sample 44. Type locality. Russia, Pushchinskiye mineral springs, sample 44, scrapes from stones (N 54.01. 616, E 158.040.972), 11.07.2021.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF84622D8CD9AE9CFCF4ED51.taxon	description	Description. LM (2 – 93). Valves lanceolate or rhombic-lanceolate, slightly asymmetric, with protracted to slightly subcapitate ends; smaller valves are elliptic or elliptic-lanceolate to roundish, with broadly rounded ends. Length 5.0 – 23.0 μm, width 4.0 – 7.0 μm. Raphe straight, filiform, distal ends bent to one side. Axial area on the raphe valve narrow, linear. Central area asymmetrical or roundish, formed by several striae being shortened on one or both sides. Striae radiate, 13 – 19 in 10 μm. Axial area on the rapheless valve narrow, linear to linear-lanceolate. A large sinus is present on one side of the valve; on the opposite side, several striae are shortened, forming a small semicircular central area. Striae weakly radiate, 13 – 18 in 10 μm. SEM (94 – 105). External central raphe ends straight, expanded, distal ends bent to one side. Internal central raphe ends slightly turned in opposite directions, distal ends terminate in faint helictoglossae. Axial area on the rapheless valve is ornamented with small circular depressions that are most concentrated on the central part of the valve. A vestigial raphe may be seen on the internal side of the rapheless valve. Striae multiseriate, composed of 2 – 4 rows of areolae on the raphe valve and 2 – 3 rows on the rapheless valve. Areolae small, round. Internally, the interstriae are distinctly raised. Sequence data. Partial 18 S rDNA gene sequence comprising V 4 domain sequences (GenBank accession number PQ 066498 for the strain kam 197, PQ 066499 for the strain kam 233, PQ 066500 for the strain kam 277, PQ 066502 for the strain kam 303, PQ 066503 for the strain kam 316, PQ 066504 for the strain kam 407) and partial rbc L sequences (GenBank accession number PQ 074208 for the strain kam 197, PQ 074209 for the strain kam 233, PQ 074210 for the strain kam 277, PQ 074212 for the strain kam 303, PQ 074213 for the strain kam 316, PQ 074214 for the strain kam 407).	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF84622D8CD9AE9CFCF4ED51.taxon	etymology	Etymology. The species is named in honour of Boris Ivanovich Piip (1906 – 1966), a renowned Russian geologist, petrographer, and volcanologist who dedicated his research to the study of volcanoes, thermal springs, and the geological structure of Kamchatka. He was the founder and first director of the Volcanology Institute at the Siberian Branch of the Academy of Sciences of the USSR, and under his leadership, the activities of the Kamchatka Branch of the Geographical Society were revived.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF84622D8CD9AE9CFCF4ED51.taxon	biology_ecology	Ecology. This species was isolated from several freshwater water bodies, including a mineral creek, from samples of benthos and epiphytes.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF84622D8CD9AE9CFCF4ED51.taxon	distribution	Distribution. As yet known only from the type locality.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF83622B8CD9AB50FCF4E3D0.taxon	materials_examined	Holotype. Slide no. kam 295, in the collection of Maxim Kulikovskiy, Institute of Plant Physiology, Russian Academy of Sciences, Russia, represented here by Figure 106. Reference strain. kam 295 (08127), isolated from sample 186. Type locality. Russia, Verkhniy Paratunskiy hot spring, sample 186, detritus (N 52.823. 669, E 158.163.369), 18.07.2021.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF83622B8CD9AB50FCF4E3D0.taxon	description	Description. LM (106 – 123). Valves small, elliptic to roundish, with broadly rounded ends. Length 6.8 – 10.0 μm, width 4.0 – 5.0 μm. Raphe straight, filiform, distal ends bent to one side. Axial area on the raphe valve narrow, linear, central area asymmetrical, wedge-shaped on one side. Striae radiate, 14 – 16 in 10 μm. Axial area on the rapheless valve narrow, linear. A sinus is present on one side of the valve; 1 – 2 striae sometimes slightly shortened on the opposite side. Striae radiate, 13 – 19 in 10 μm. SEM (124 – 127). External central raphe ends straight, slightly expanded, distal ends bent to one side and extended onto the valve mantle. Internal central raphe ends slightly turned in opposite directions, distal ends terminate in small helictoglossae. The sinus is relatively large, rounded. Axial area on the rapheless valve is ornamented very faintly with small circular depressions. Striae multiseriate, composed of 2 – 3 rows of areolae on both valves. Areolae small, round. Internally, the interstriae are distinctly raised. Sequence data. Partial 18 S rDNA gene sequence comprising V 4 domain sequence (GenBank accession number PQ 066501) and partial rbc L sequence (GenBank accession number PQ 074211) for the strain kam 295.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF83622B8CD9AB50FCF4E3D0.taxon	etymology	Etymology. The species is named in honour of Prokopy Trifonovich Novograblenov (1892 – 1934), a prominent Russian local historian and researcher of Kamchatka who authored the works Volcanoes of Kamchatka and Hot Springs of Kamchatka. For many years, he led the Kamchatka Museum and Local History Society, and supervised the publication of guidelines for naturalists on observing earthquakes and volcanoes and the restoration of a seismological station.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF83622B8CD9AB50FCF4E3D0.taxon	biology_ecology	Ecology. This species was isolated from a benthos sample from a hot spring.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
03A38797FF83622B8CD9AB50FCF4E3D0.taxon	distribution	Distribution. As yet known only from the type locality.	en	Tseplik, Natalia, Maltsev, Yevhen, Glushchenko, Anton, Genkal, Sergey, Kulikovskiy, Maxim (2024): Two new Planothidium (Achnanthidiaceae, Bacillariophyceae) species with a sinus from the Kamchatka Peninsula, Russia. Phytotaxa 664 (2): 111-122, DOI: 10.11646/phytotaxa.664.2.3, URL: https://doi.org/10.11646/phytotaxa.664.2.3
