Abstract
Platessa arborea sp. nov. new monoraphid diatom species is described from the tree moss habitat of India’s Sikkim state from the Eastern Himalayan biodiversity hotspot. This new species was described based on light and scanning electron micrographs and compared to morphologically similar taxa. Platessa arborea seems to have an affinity for the aerial habitat and has certain unique morphological features distinct from all the other Platessa species, such as its narrowly rounded apices, wide axial area, and the presence of predominantly uniseriate striae with unusually thick striae density. In India, there have been previous reports of some species from the genera Achnanthes and Cocconeis, which have been eventually transferred to the genus Platessa. However, this is the first formal documentation of the Platessa genus from India.
References
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<p>Krasske, G. (1929) Beiträge zur Kenntnis der Diatomeenflora Sachsens. <em>Botanisches Archiv</em> 27: 348–380.</p>
<p>Krasske, G. (1932) Beitrage. zur Kenntnis der Diatomeenflora der Alpen. <em>Hedwigia</em> 72: 92–131.</p>
<p>Krasske, G. (1933) Über Kieselgur-Geschiebe von Oderberg-Bralitz. Archiv für Geschiebeforschung 9: 84–95.</p>
<p>Kulikovskiy, M.S., Glushchenko, A.M., Genkal, S.I., Kuznetsova, I.V. & Kociolek, J.P. (2020) <em>Platebaikalia</em> – a new monoraphid diatom genus from ancient Lake Baikal with comments on the genus Platessa. <em>Fottea, Olomouc</em> 20: 58–67. https://doi.org/10.5507/fot.2019.014</p>
<p>Lowe, R.L., Furey, P.C., Ress, J.A. & Johansen, J.R. (2007) Diatom biodiversity and distribution on wetwalls in Great Smokey Mountains National Park. <em>Southeastern Naturalist</em> 6: 135–152. https://doi.org/10.1656/1528-7092(2007)6[135:DBADOW]2.0.CO;2</p>
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<p>Mayer, A. (1919) Bacillariales von Reichenhall und Umgebung. <em>Kryptogamische Forschungen herausgegeben von der Kryptogamenkommission der Bayerischen Botanischen Gesellschaft zur Erforschung der heimischen Flora</em> 1: 191–216.</p>
<p>Morin, S. & Coste, M. (2006) Metal-induced shifts in the morphology of diatoms from the Riou Mort and Riou Viou streams (South West France). <em>In</em>: Ács, É., Kiss, K.T., Padisák, J. & Szabó, K (Eds.) <em>Use of algae for monitoring rivers</em> <em>VI</em>. Hungarian Algological Society, Göd, pp. 91–106.</p>
<p>Pinseel, E., Janssens, S.B., Verleyen, E., Vanormelingen, P., Kohler, T.J., Biersma, E.M., Sabbe, K., Van de Vijver, B. & Vyverman, W. (2020) Global Radiation in a Rare Biosphere Soil Diatom. – <em>Nature communications</em> 11: 1–12. https://doi.org/10.1038/s41467-020-16181-0 </p>
<p>Romero, O.E. (2016) Study of the type material of two <em>Platessa</em> Lange-Bertalot species (formerly <em>Cocconeis brevicostata</em> Hust. and <em>Cocconeis cataractarum</em> Hust.(Bacillariophyta). <em>Diatom Research</em> 31: 63–75. https://doi.org/10.1080/0269249X.2016.1143035</p>
<p>Round, F.E., Crawford, R.M. & Mann, D.G. (1990) The Diatoms. Biology and Morphology of the Genera. Cambridge Univ. Press, Cambridge, 747 pp.</p>
<p>Schmidt, A., Schmidt, M., Fricke, F., Heiden, H., Müller, O. & Hustedt, F. (1972) 1874–1959.<em> Atlas der Diatomaceen-kunde. </em>R. Reisland, Leipzig, pp. 472.</p>
<p>Schofield, W.B. (2019) “Bryophyte”. <em>Encyclopedia Britannica</em>. Available from: https://www.britannica.com/plant/bryophyte (Accessed 29 January 2022)</p>
<p>Seetharam, K. (2008) Climate change scenario over Gangtok. <em>Mausam</em> 59: 361–366.</p>
<p>Silva, P.C. (1962) Classification of algae.<em> In: </em>Lewin, R.A. (Ed.)<em> Physiology and Biochemistry of Algae.</em> New York & London: Academic Press. pp. 827–837.</p>
<p>Silva, J.F., Oliveira, M.A., Anunciação, R.R, Silva, E.P., Alves, R.P., Schünemann, A.L., Victoria, F.C., De Albuquerque, M.P. & Pereira, A.B. (2019) Distribution of aerophilous diatom communities associated with terrestrial green macroalgae in the South Shetland Islands, Maritime Antarctica. <em>PLoS ONE</em> 14 (12). https://doi.org/10.1371/journal.pone.0226691</p>
<p>Smol, J.P. & Stoermer, E.F. (2010) <em>The Diatoms: Applications to the Environmental and Earth Sciences</em>, 2nd ed. Cambridge University Press, Cambridge, UK..</p>
<p>Suxena, M.R. & Venkateswarlu, V. (1968) Algae of the Cho Oyu (E. Himalaya) Expedition- I. Bacillariophyceae. <em>Hydrobiologia</em> 32: 1–26.</p>
<p>Suxena, M.R., Venkateswarlu, V. & Rao, V. (1972) Algae of the Cho-Oyu (E. Himalayas) expedition-II, Bacillariophyceae-II. <em>Nova Hedwigia</em> 23: 415–426.</p>
<p>Tudesque, L., Le Cohu, R. & Wetzel, C.E. (2016) Two new <em>Platessa</em> (Bacillariophyceae) from Amazonia: <em>Platessa guianensis</em> spec. nov., and <em>P. itoupensis </em>spec. nov. <em>Phytotaxa</em> 267: 237–255. https://doi.org/10.11646/phytotaxa.267.4.1</p>
<p>Van de Vijver, B. & Beyens, L. (1997) The epiphytic diatom flora of mosses from Strømness Bay area, South Georgia. <em>Polar Biology</em> 17: 492–501.</p>
<p>Van de Vijver, B., Van Kerckvoorde, A. & Beyens, L. (2003) Freshwater and terrestrial moss diatom assemblages of the Cambridge Bay area, Victoria Island (Nunavut, Canada). <em>Nova Hedwigia</em> 76: 225–243. https://doi.org/10.1127/0029-5035/2003/0076-0225</p>
<p>Vijverman, W. & Compère, P. (1991) <em>Nupela</em> <em>giluwensis</em> gen. & spec. nov. A new genus of naviculoid diatoms. <em>Diatom</em> <em>Research</em> 6: 175–179. https://doi.org/10.1080/0269249X.1991.9705156</p>
<p>Verma, J. & Nautiyal, P. (2009) Longitudinal patterns of distribution of epilithic diatoms in a lesser Himalayan stream. <em>Journal of Hill Research</em> 22: 105–109.</p>
<p>Alakananda, B., Mahesh, M.K. & Ramachandra, T.V. (2013) Role of environmental variables in diatom distribution in urban wetlands of Peninsular India. <em>Diatom</em> 29: 1–11.</p>
<p>Bory de Saint-Vincent, J.B.G.M. (1822) <em>Achnanthe</em>. <em>Achnanthes</em>. <em>Dictionnaire Classique d’Histoire Naturelle</em> 1: 79–80.</p>
<p>Cao, W., Xiong, Y.X., Zhao, D.G., Tan, H.Y. & Qu, J.J. (2020) Bryophytes and the symbiotic microorganisms, the pioneers of vegetation restoration in karst rocky desertification areas in southwestern China. <em>Applied microbiology and biotechnology</em> 104: 873–891. https://doi.org/10.1007/s00253-019-10235-0</p>
<p>Cattaneo, A., Couillard, Y., Wunsam, S. & Courcelles, M. (2004) Diatom taxonomic and morphological changes as indicators of metal pollution and recovery in Lac Dufault (Québec, Canada). <em>Journal of paleolimnology</em> 32: 163–175. https://doi.org/10.1023/B:JOPL.0000029430.78278.a5</p>
<p>Das, S.K., Rawat, D.S., Dash, S.S., Banerjee, A., Sinha, B.K. & Singh, P. (2020) Moss-inhabiting diatoms as ecological indicators in Neora Valley National Park (Eastern Himalaya), India. <em>Tropical Ecology</em> 61: 226–237. https://doi.org/10.1007/s42965-020-00083-9</p>
<p>Ehrenberg, C.G. (1836) Zusätze zur Erkenntniss grosser organischer Ausbildung in den kleinsten thierischen Organismen. <em>Abhandlungen der Königlichen Akademie der Wissenschaften zu Berlin </em>1835: 150–181.</p>
<p>Ehrenberg, C.G. (1837) Über ein aus fossilen Infusorien bestehendes, 1832 zu Brod verbacknes Bergmehl von den Grenzen Lapplands in Schweden<em>. Bericht über die zur Bekanntmachung geeigneten Verhandlungen der Königl. Preuß. Akademie der Wissenschaften zu Berlin Erster Jarhrgang</em> 43–45.</p>
<p>Enache, M.D., Potapova, M. & Morales, E.A. (2014) <em>Platessa</em> <em>strelnikovae</em> (Bacillariophyta), a new species from Maine and Vermont lakes, USA. <em>Beiheft zur Nova Hedwigia</em> 143: 239–244.</p>
<p>Foged, N. (1959) Diatoms from Afghanistan. Biologiske Skrifter udgivet af Det Kongelige Danske Videnskabernes Selskab 11: 1–95.</p>
<p>Gremmen, N.J., Van De Vijver, B., Frenot, Y. & Lebouvier, M. (2007) Distribution of moss-inhabiting diatoms along an altitudinal gradient at sub-Antarctic Îles Kerguelen. <em>Antarctic Science</em> 19: 17–24. https://doi.org/10.1017/S0954102007000041</p>
<p>Haeckel, E. (1878) <em>Das Protistenreich. Eine populare Übersicht über das For-mengebiet der niedersten Lebewesen. Mit einem wissenschaftlichen Anhang: System der Protisten. </em>Ernst Günther, Leipzig, 104 pp. https://doi.org/10.5962/bhl.title.58542</p>
<p>Huizhong, Z. & Jiayou, C. (2000) <em>Bacillariophyta of the Xizang Plateau.</em> Science Press, Beijing, China. 353 pp.</p>
<p>Johansen, J.R. (2010) Diatoms of aerial habitats. <em>In:</em> Stoermer, E.F. & Smol, J.P. (eds.) <em>The diatoms: applications for the environmental and earth sciences. Cambridge</em>: Cambridge University Press, pp. 264–273.</p>
<p>Kharkongar, D. & Ramanujam, P. (2014) Diversity and species composition of subaerial algal communities in forested area of Meghalaya, India. <em>International Journal of Biodiversity</em> 2014: 1–10. https://dx.doi.org/10.1155/2014/456202</p>
<p>Krammer, K. & Lange-Bertalot, H. (2004) Bacillariophyceae 4. Teil: Achnanthaceae, Kritische Erganzungen zu <em>Navicula</em> (Lineolatae), <em>Gomphonema</em>. Gesamtliteraturverzeichnis Teil 1-4 [second revised edition] [With “Ergänzungen und Revisionen” by H. Lange Bertalot].<em> In: Süßwasserflora von Mitteleuropa</em> (Ettl, H. <em>et al.</em> Eds) Vol. 2, pp. 1–468.</p>
<p>Krasske, G. (1929) Beiträge zur Kenntnis der Diatomeenflora Sachsens. <em>Botanisches Archiv</em> 27: 348–380.</p>
<p>Krasske, G. (1932) Beitrage. zur Kenntnis der Diatomeenflora der Alpen. <em>Hedwigia</em> 72: 92–131.</p>
<p>Krasske, G. (1933) Über Kieselgur-Geschiebe von Oderberg-Bralitz. Archiv für Geschiebeforschung 9: 84–95.</p>
<p>Kulikovskiy, M.S., Glushchenko, A.M., Genkal, S.I., Kuznetsova, I.V. & Kociolek, J.P. (2020) <em>Platebaikalia</em> – a new monoraphid diatom genus from ancient Lake Baikal with comments on the genus Platessa. <em>Fottea, Olomouc</em> 20: 58–67. https://doi.org/10.5507/fot.2019.014</p>
<p>Lowe, R.L., Furey, P.C., Ress, J.A. & Johansen, J.R. (2007) Diatom biodiversity and distribution on wetwalls in Great Smokey Mountains National Park. <em>Southeastern Naturalist</em> 6: 135–152. https://doi.org/10.1656/1528-7092(2007)6[135:DBADOW]2.0.CO;2</p>
<p>Lowe, R.L., Kociolek, P., Johansen, J.R., Van De Vijver, B., Lange-Bertalot, H. & Kopalová, K. (2014) <em>Humidophila</em> gen. nov., a new genus for a group of diatoms (Bacillariophyta) formerly within the genus <em>Diadesmis</em>: species from Hawai’i, including one new species. <em>Diatom Research</em> 29: 351–360. https://doi.org/10.1080/0269249X.2014.889039</p>
<p>Mayer, A. (1919) Bacillariales von Reichenhall und Umgebung. <em>Kryptogamische Forschungen herausgegeben von der Kryptogamenkommission der Bayerischen Botanischen Gesellschaft zur Erforschung der heimischen Flora</em> 1: 191–216.</p>
<p>Morin, S. & Coste, M. (2006) Metal-induced shifts in the morphology of diatoms from the Riou Mort and Riou Viou streams (South West France). <em>In</em>: Ács, É., Kiss, K.T., Padisák, J. & Szabó, K (Eds.) <em>Use of algae for monitoring rivers</em> <em>VI</em>. Hungarian Algological Society, Göd, pp. 91–106.</p>
<p>Pinseel, E., Janssens, S.B., Verleyen, E., Vanormelingen, P., Kohler, T.J., Biersma, E.M., Sabbe, K., Van de Vijver, B. & Vyverman, W. (2020) Global Radiation in a Rare Biosphere Soil Diatom. – <em>Nature communications</em> 11: 1–12. https://doi.org/10.1038/s41467-020-16181-0 </p>
<p>Romero, O.E. (2016) Study of the type material of two <em>Platessa</em> Lange-Bertalot species (formerly <em>Cocconeis brevicostata</em> Hust. and <em>Cocconeis cataractarum</em> Hust.(Bacillariophyta). <em>Diatom Research</em> 31: 63–75. https://doi.org/10.1080/0269249X.2016.1143035</p>
<p>Round, F.E., Crawford, R.M. & Mann, D.G. (1990) The Diatoms. Biology and Morphology of the Genera. Cambridge Univ. Press, Cambridge, 747 pp.</p>
<p>Schmidt, A., Schmidt, M., Fricke, F., Heiden, H., Müller, O. & Hustedt, F. (1972) 1874–1959.<em> Atlas der Diatomaceen-kunde. </em>R. Reisland, Leipzig, pp. 472.</p>
<p>Schofield, W.B. (2019) “Bryophyte”. <em>Encyclopedia Britannica</em>. Available from: https://www.britannica.com/plant/bryophyte (Accessed 29 January 2022)</p>
<p>Seetharam, K. (2008) Climate change scenario over Gangtok. <em>Mausam</em> 59: 361–366.</p>
<p>Silva, P.C. (1962) Classification of algae.<em> In: </em>Lewin, R.A. (Ed.)<em> Physiology and Biochemistry of Algae.</em> New York & London: Academic Press. pp. 827–837.</p>
<p>Silva, J.F., Oliveira, M.A., Anunciação, R.R, Silva, E.P., Alves, R.P., Schünemann, A.L., Victoria, F.C., De Albuquerque, M.P. & Pereira, A.B. (2019) Distribution of aerophilous diatom communities associated with terrestrial green macroalgae in the South Shetland Islands, Maritime Antarctica. <em>PLoS ONE</em> 14 (12). https://doi.org/10.1371/journal.pone.0226691</p>
<p>Smol, J.P. & Stoermer, E.F. (2010) <em>The Diatoms: Applications to the Environmental and Earth Sciences</em>, 2nd ed. Cambridge University Press, Cambridge, UK..</p>
<p>Suxena, M.R. & Venkateswarlu, V. (1968) Algae of the Cho Oyu (E. Himalaya) Expedition- I. Bacillariophyceae. <em>Hydrobiologia</em> 32: 1–26.</p>
<p>Suxena, M.R., Venkateswarlu, V. & Rao, V. (1972) Algae of the Cho-Oyu (E. Himalayas) expedition-II, Bacillariophyceae-II. <em>Nova Hedwigia</em> 23: 415–426.</p>
<p>Tudesque, L., Le Cohu, R. & Wetzel, C.E. (2016) Two new <em>Platessa</em> (Bacillariophyceae) from Amazonia: <em>Platessa guianensis</em> spec. nov., and <em>P. itoupensis </em>spec. nov. <em>Phytotaxa</em> 267: 237–255. https://doi.org/10.11646/phytotaxa.267.4.1</p>
<p>Van de Vijver, B. & Beyens, L. (1997) The epiphytic diatom flora of mosses from Strømness Bay area, South Georgia. <em>Polar Biology</em> 17: 492–501.</p>
<p>Van de Vijver, B., Van Kerckvoorde, A. & Beyens, L. (2003) Freshwater and terrestrial moss diatom assemblages of the Cambridge Bay area, Victoria Island (Nunavut, Canada). <em>Nova Hedwigia</em> 76: 225–243. https://doi.org/10.1127/0029-5035/2003/0076-0225</p>
<p>Vijverman, W. & Compère, P. (1991) <em>Nupela</em> <em>giluwensis</em> gen. & spec. nov. A new genus of naviculoid diatoms. <em>Diatom</em> <em>Research</em> 6: 175–179. https://doi.org/10.1080/0269249X.1991.9705156</p>
<p>Verma, J. & Nautiyal, P. (2009) Longitudinal patterns of distribution of epilithic diatoms in a lesser Himalayan stream. <em>Journal of Hill Research</em> 22: 105–109.</p>