Abstract
A new species belonging to the genus Hippodonta is described, Hippodonta mudumalaiensis, from Mudumalai, Tamil Nadu, India. This paper analysed a detailed morphology and ultrastructure of H. mudumalaiensis based on LM and SEM observations and compared it with similar species within the genus. The new species belongs to group two of Hippodonta, with the characteristic features of narrow lanceolate valve outline, protracted to broadly rounded apices and rhombic to panduriform central area. The described species is our prime effort to report genus Hippodonta from India, aiding in microbial biodiversity assessment of the country. Additionally, Hippodonta of the Indian Subcontinent is also discussed.
References
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<p>Maltsev, Y., Kezlya, E., Maltseva, S., Karthick, B., Dvořák, P., Kociolek, J.P. & Kulikovskiy, M. (2021) A new species of the previously monotypic genus <em>Iningainema</em> (Cyanobacteria, Scytonemataceae) from the Western Ghats, India. <em>European Journal of Phycology</em> 56: 348–358.</p>
<p>Medlin, L.K. & Kaczmarska, I. (2004) Evolution of the diatoms: V. Morphological and cytological support for the major clades and a taxonomic revision. <em>Phycologia </em>43: 245–270. https://doi.org/10.2216/i0031-8884-43-3-245.1</p>
<p>Myers, N., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A.B. & Kent, J. (2000) Biodiversity hotspots for conservation priorities. <em>Nature</em> 403: 853–858. https://doi.org/10.1038/35002501</p>
<p>Østrup, E. (1910) <em>Danske Diatoméer</em>. C.A. Reitzels Boghandel, Copenhagen. 323 pp.</p>
<p>Pavlov, A., Levkov, Z., Williams, D.M. & Edlund, M.B. (2013) Observations on <em>Hippodonta </em>(Bacillariophyceae) in selected ancient lakes. <em>Phytotaxa </em>90: 1–53. https://doi.org/10.11646/phytotaxa.90.1.1</p>
<p>Peng, Y.M., Rioual, P., Levkov, Z., Williams, D.M. & Jin, Z.D. (2014) Morphology and ultrastructure of <em>Hippodonta qinghainensis </em>sp. nov. (Bacillariophyceae), a new diatom from Lake Qinghai, China. <em>Phytotaxa </em>186: 61–074. https://doi.org/10.11646/phytotaxa.186.2.1</p>
<p>Radhakrishnan, C., Pardhi, S., Kulikovskiy, M., Kociolek, J.P. & Karthick, B. (2020) <em>Navicula watveae</em> sp. nov. (Bacillariophyceae) a new diatom species from the Western Ghats, India. <em>Phytotaxa</em> 433: 20–26. https://doi.org/10.11646/phytotaxa.433.1.3</p>
<p>Ross, R., Cox, E.J., Karayeva, N.I., Mann, D.G., Paddock, T.B.B., Simonsen, R. & Sims, P.A. (1979) An amended terminology for the siliceous components of the diatom cell. <em>Nova Hedwigia, Beiheft </em>64: 513–533.</p>
<p>Round, F.E., Crawford, R.M. & Mann, D.G. (1990) <em>The Diatoms</em>.<em> Biology and Morphology of the Genera</em>. Cambridge Univ. Press, Cambridge, 747 pp.</p>
<p>Silva, P.C. (1962) Classification of algae. <em>In</em>: Lewin, R.A. (ed.) <em>Physiology and biochemistry of algae</em>. Academic Press, New York and London, pp. 827–837.</p>
<p>Somashekar, R.K. (1984) Contribution to the algal flora of river Kapila, Karnataka, II Diatoms. <em>Phykos</em> 23: 125–129.</p>
<p>Sreekumar, R. & Joseph, K.J. (1995) Periphytic flora of Cochin backwaters. <em>Phykos</em> 34: 83–89.</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>Vigneshwaran, A., Karthick, B., Kulikovskiy, M.S., Glushchenko, A. & Kociolek, J.P. (2019) A new species of <em>Cymbella</em> (Bacillariophyceae, cymbellaceae) from the Pavana river, Western Ghats, India. <em>Phytotaxa</em> 395: 209–218. https://doi.org/10.11646/phytotaxa.395.3.5</p>
<p>Vijayakumar, S.P., Dinesh, K.P., Prabhu, M.V. & Shanker, K. (2014) Lineage delimitation and description of nine new species of bush frogs (<em>Anura</em>: <em>Raorchestes</em>, Rhacophoridae) from the Western Ghats Escarpment. <em>Zootaxa</em> 3893: 451–488. https://doi.org/10.11646/zootaxa.3893.4.1</p>
<p>Thacker, M., Roy, S., Kociolek, J.P., Lowe, R.L. & Karthick, B. (2019) A new species of <em>Germainiella</em> (Bacillariophyta) from the <em>Myristica</em> swamps of the Western Ghats, India. <em>Diatom Research</em> 34: 181–191. https://doi.org/10.1080/0269249X.2019.1671236</p>
<p>Trivedy, R.K. (1982) Some observations on algal flora of Jaipur, Rajasthan. <em>Phykos</em> 21: 160–163.</p>
<p>Wadmare, N., Baghela, A., Kociolek, J.P. & Karthick, B. (2021) Description and phylogenetic position of three new species of <em>Stauroneis</em> Ehrenberg (Bacillariophyceae: Stauroneidaceae) from the Indian Subcontinent. <em>European Journal of Phycology</em> 57: 48–67. https://doi.org/10.1080/09670262.2021.1888390</p>
<p>Zhao, L., Sun, J.D., Gao, Y.H., Liang, J.R., Sun, L., Li, X.S. & Chen, C.P. (2017) <em>Hippodonta fujiannensis </em>sp. nov. (Bacillariophyceae), a new diatom from the low intertidal zone, Fujian Province, China. <em>Phytotaxa</em> 295: 77–85. https://doi.org/10.11646/phytotaxa.295.1.7</p>
<p>Blanco, S., Van de Vijver, B., Vinocur, A., Mataloni, G., Gomà, J., Novais, M.H. & Ector, L. (2012) <em>Hippodonta lange-bertalotii </em>Van de Vijver, Mataloni & Vinocur sp. nov. and related small celled <em>Hippodonta </em>taxa. <em>Nova Hedwigia, Beiheft </em>141: 39–52.</p>
<p>Bory de Saint-Vincent, J.B.G.M. (1822) Bacillarées. <em>Dictionnaire</em> <em>Classique d’Histoire naturelle</em> 2: 127–129.</p>
<p>Bruder, K. & Medlin, L.K. (2008) Morphological and molecular investigations of naviculoid diatoms. III. <em>Hippodonta </em>and <em>Navicula </em>s. s. <em>Diatom Research </em>23: 331–347. https://doi.org/10.1080/0269249X.2008.9705759</p>
<p>Chadha, A. & Pandey, D.C. (1984) Algal-Flora of Allahabad, Part IV A general Account. <em>In:</em> Cramer, J. (eds.) <em>Algae of the Indian Subcontinent a collection of papers</em>. In der A.R. Ganter Verlag Kommanditgesellschaft, Vaduz. pp. 128–141.</p>
<p>Cleve, P.T. & Grunow, A. (1880) Beiträge zur Kenntniss der arctischen Diatomeen. <em>Kongliga Svenska Vetenskaps-Akademiens Handlingar</em> 17: 1–121.</p>
<p>Cox, E.J. (1999) Studies on the diatom genus <em>Navicula </em>Bory. VIII. Variation in valve morphology in relation to the generic diagnosis based on <em>Navicula tripunctata </em>(O.F. Müller) Bory. <em>Diatom Research </em>14: 207–237. https://dx.doi.org/10.1080/0269249X.1999.9705467</p>
<p>Ehrenberg, C.G. (1838) Die Infusionsthierchen als vollkommene Organismen. Ein Blick in das tiefere organische Leben der Natur. Leipzig: Verlag von Leopold Voss. 547 pp.</p>
<p>Foged, N. (1959) Diatoms from Afghanistan. <em>Biologiske Skrifter udgivet af Det Kongelige Danske Videnskabernes Selskab</em> 11: 1–95.</p>
<p>Foged, N. (1976) Freshwater diatoms in Sri Lanka (Ceylon). <em>In</em>: Cramer, J. (eds.) <em>A.R. Ganter Verlag Kommanditgesellschaft.</em></p>
<p>Garg, S., Suyesh, R., Das, S., Bee, M.A. & Biju, S.D. (2021) An integrative approach to infer systematic relationships and define species groups in the shrub frog genus <em>Raorchestes</em>, with description of five new species from the Western Ghats, India. <em>PeerJ</em> 9: e10791. https://doi.org/10.7717/peerj.10791</p>
<p>Grunow, A. (1860) Über neue oder ungenügend gekannte Algen. Erste Folge, Diatomeen, Familie Naviculaceen. <em>Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wein</em> 10: 503–582.</p>
<p>Grunow, A. (1882) Beiträge zur Kenntniss der fossilen Diatomeen Österreich-Ungarns. <em>Beiträge zur Paläontologie Österreich-Ungarns und des Orients </em>2: 136–159.</p>
<p>Haeckel, E. (1878) <em>Das Protistenreich</em>. Eine populare Übersicht über das For-mengebiet der niedersten Lebewesen. Mit einem wissenschaftlichen Anhang: System der Protisten. Ernst Günther, Leipzig, 104 pp. https://doi.org/10.5962/bhl.title.58542</p>
<p>Harrington, B. (2004–2005) <em>Inkscape</em>. Available from: http://www.inkscape.org (accessed 26 August 2020)</p>
<p>Hustedt, F. (1922) Bacillariales aus Innerasien. Gesammelt von Dr. Sven Hedin.<em> In: </em>Hedin, S. (Ed.) Southern Tibet, discoveries in former times compared with my own researches in 1906-1908. <em>Lithographic Institute of the General Staff of the Swedish Army</em>, Stockholm. 6: 107–152.</p>
<p>Karthick, B., Taylor, J.C., Mahesh, M.K. & Ramachandra, T.V. (2010) Protocols for collection, preservation and enumeration of diatoms from aquatic habitats for water quality monitoring in India. <em>The ICF Journal of Soil and Water Sciences</em> 3: 1–36.</p>
<p>Kützing, F. (1844) <em>Die Kieselschaligen Bacillarien oder Diatomeen.</em> Nordhausen: W. Köhne, 152 pp. https://doi.org/10.5962/bhl.title.64360</p>
<p>Kociolek, J.P., Blanco, S., Coste, M., Ector, L., Liu, Y., Karthick, B., Kulikovskiy, M., Lundholm, N., Ludwig, T., Potapova, M., Rimet, F., Sabbe, K., Sala, S., Sar, E., Taylor, J., Van de Vijver, B., Wetzel, C.E., Williams, D.M., Witkowski, A. & Witkowski, J. (2022) DiatomBase. Available from: https://www.diatombase.org (accessed 26 August 2021)</p>
<p>Lange-Bertalot, H., Metzeltin, D. & Witkowski, A. (1996) <em>Hippodonta </em>gen. nov. Umschreibung und Begründung einer neuen Gattung der Naviculaceae. <em>In</em>: Lange-Bertalot, H. (Ed.) <em>Iconographia Diatomologica </em>4: 247–274.</p>
<p>Lokhande, V., Radhakrishnan, C., Kociolek, J.P., Lowe, R. & Karthick, B. (2020) The diatom genus <em>Luticola</em> D.G. Mann (Bacillariophyceae) in the Western Ghats of India and its biogeography. <em>European Journal of Phycology</em> 56: 142–158. https://doi.org/10.1080/09670262.2020.1783460</p>
<p>Maltsev, Y., Kezlya, E., Maltseva, S., Karthick, B., Dvořák, P., Kociolek, J.P. & Kulikovskiy, M. (2021) A new species of the previously monotypic genus <em>Iningainema</em> (Cyanobacteria, Scytonemataceae) from the Western Ghats, India. <em>European Journal of Phycology</em> 56: 348–358.</p>
<p>Medlin, L.K. & Kaczmarska, I. (2004) Evolution of the diatoms: V. Morphological and cytological support for the major clades and a taxonomic revision. <em>Phycologia </em>43: 245–270. https://doi.org/10.2216/i0031-8884-43-3-245.1</p>
<p>Myers, N., Mittermeier, R.A., Mittermeier, C.G., da Fonseca, G.A.B. & Kent, J. (2000) Biodiversity hotspots for conservation priorities. <em>Nature</em> 403: 853–858. https://doi.org/10.1038/35002501</p>
<p>Østrup, E. (1910) <em>Danske Diatoméer</em>. C.A. Reitzels Boghandel, Copenhagen. 323 pp.</p>
<p>Pavlov, A., Levkov, Z., Williams, D.M. & Edlund, M.B. (2013) Observations on <em>Hippodonta </em>(Bacillariophyceae) in selected ancient lakes. <em>Phytotaxa </em>90: 1–53. https://doi.org/10.11646/phytotaxa.90.1.1</p>
<p>Peng, Y.M., Rioual, P., Levkov, Z., Williams, D.M. & Jin, Z.D. (2014) Morphology and ultrastructure of <em>Hippodonta qinghainensis </em>sp. nov. (Bacillariophyceae), a new diatom from Lake Qinghai, China. <em>Phytotaxa </em>186: 61–074. https://doi.org/10.11646/phytotaxa.186.2.1</p>
<p>Radhakrishnan, C., Pardhi, S., Kulikovskiy, M., Kociolek, J.P. & Karthick, B. (2020) <em>Navicula watveae</em> sp. nov. (Bacillariophyceae) a new diatom species from the Western Ghats, India. <em>Phytotaxa</em> 433: 20–26. https://doi.org/10.11646/phytotaxa.433.1.3</p>
<p>Ross, R., Cox, E.J., Karayeva, N.I., Mann, D.G., Paddock, T.B.B., Simonsen, R. & Sims, P.A. (1979) An amended terminology for the siliceous components of the diatom cell. <em>Nova Hedwigia, Beiheft </em>64: 513–533.</p>
<p>Round, F.E., Crawford, R.M. & Mann, D.G. (1990) <em>The Diatoms</em>.<em> Biology and Morphology of the Genera</em>. Cambridge Univ. Press, Cambridge, 747 pp.</p>
<p>Silva, P.C. (1962) Classification of algae. <em>In</em>: Lewin, R.A. (ed.) <em>Physiology and biochemistry of algae</em>. Academic Press, New York and London, pp. 827–837.</p>
<p>Somashekar, R.K. (1984) Contribution to the algal flora of river Kapila, Karnataka, II Diatoms. <em>Phykos</em> 23: 125–129.</p>
<p>Sreekumar, R. & Joseph, K.J. (1995) Periphytic flora of Cochin backwaters. <em>Phykos</em> 34: 83–89.</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>Vigneshwaran, A., Karthick, B., Kulikovskiy, M.S., Glushchenko, A. & Kociolek, J.P. (2019) A new species of <em>Cymbella</em> (Bacillariophyceae, cymbellaceae) from the Pavana river, Western Ghats, India. <em>Phytotaxa</em> 395: 209–218. https://doi.org/10.11646/phytotaxa.395.3.5</p>
<p>Vijayakumar, S.P., Dinesh, K.P., Prabhu, M.V. & Shanker, K. (2014) Lineage delimitation and description of nine new species of bush frogs (<em>Anura</em>: <em>Raorchestes</em>, Rhacophoridae) from the Western Ghats Escarpment. <em>Zootaxa</em> 3893: 451–488. https://doi.org/10.11646/zootaxa.3893.4.1</p>
<p>Thacker, M., Roy, S., Kociolek, J.P., Lowe, R.L. & Karthick, B. (2019) A new species of <em>Germainiella</em> (Bacillariophyta) from the <em>Myristica</em> swamps of the Western Ghats, India. <em>Diatom Research</em> 34: 181–191. https://doi.org/10.1080/0269249X.2019.1671236</p>
<p>Trivedy, R.K. (1982) Some observations on algal flora of Jaipur, Rajasthan. <em>Phykos</em> 21: 160–163.</p>
<p>Wadmare, N., Baghela, A., Kociolek, J.P. & Karthick, B. (2021) Description and phylogenetic position of three new species of <em>Stauroneis</em> Ehrenberg (Bacillariophyceae: Stauroneidaceae) from the Indian Subcontinent. <em>European Journal of Phycology</em> 57: 48–67. https://doi.org/10.1080/09670262.2021.1888390</p>
<p>Zhao, L., Sun, J.D., Gao, Y.H., Liang, J.R., Sun, L., Li, X.S. & Chen, C.P. (2017) <em>Hippodonta fujiannensis </em>sp. nov. (Bacillariophyceae), a new diatom from the low intertidal zone, Fujian Province, China. <em>Phytotaxa</em> 295: 77–85. https://doi.org/10.11646/phytotaxa.295.1.7</p>