Abstract
Impatiens jacobdevlasii Herath, C. Bandara & Gopallawa sp. nov. (Balsaminaceae), a new species from Knuckles (Dumbara) massif of Sri Lanka is described and illustrated. The detailed morphological characters, diagnostic comparisons, notes on habitat and ecology are presented. According to the IUCN Red List Categories and Criteria, I. jacobdevlasii is assessed as Critically Endangered (CR) by virtue of its limited distribution range and decline of mature individuals.
References
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<p>Bambaradeniya, C.N.B. & Ekanayake, S.P. (2003) <em>A Guide to the Biodiversity of Knuckles Forest Region</em>. IUCN–The World Conservation Union, Sri Lanka Country Office, Colombo, Sri Lanka. vi + 68 pp.</p>
<p>Bhaskar, V. (2012) <em>Taxonomic Monograph on Impatiens </em>L.<em> (Balsaminaceae) of Western Ghats, South India: the Key Genus for Endemism</em>. Bangalore: Centre for plant taxonomic studies. 283 pp.</p>
<p>de Vlas., J. (2019) <em>Illustrated field guide to the flowers of Sri Lanka</em>. Volume 3. J. de Vlas, The Netherlands. 320 pp.</p>
<p>Grey-Wilson, C. (1980) <em>Impatiens of Africa.</em> Rotterdam, Balkema.</p>
<p>Grey-Wilson, C. (1985) Balsaminaceae.<em> In: </em>Dassanayake, M.D. & Fosberg, F.R. (Ed.) <em>A revised handbook of the Flora of Ceylon</em>. Amerind publication Co. Pvt. Ltd., New Delhi. pp. 76–120.</p>
<p>Gunatilleke, C.V.S., Ashton, P.S. (1987) New light on the plant geography of Ceylon. II. The ecological biogeography of the lowland endemic tree flora. <em>Journal of Biogeography</em> 14 (4): 295–327. https://doi.org/10.2307/2844940</p>
<p>Hooker, J.D. (1875) <em>Impatiens</em> L.<em> In:</em> <em>Flora of British India</em> 1. L. Reeve & Co., London, UK. pp. 440–464.</p>
<p>IUCN Standards and Petitions Committee (2019) Guidelines for Using the IUCN Red List Categories and Criteria. Version 14. Prepared by the Standards and Petitions Committee; https://www.iucnredlist.org/documents/RedListGuidelines.pdf (accessed on 12 December 2019)</p>
<p>Mabberley, D.J. (2008) <em>The plant book: a portable dictionary of the vascular plants</em>. 3<sup>rd</sup> edition. Cambridge: Cambridge University Press.</p>
<p>Mittermeier, R.A., Robles, G., Hoffman, M., Pilgrim, J., Brooks, T., Mittermeier, C.G., Lamoreux, J. & da Fonseca, G.A.B. (Eds.) (2004) <em>Hotspots revisited: Earth’s biologically richest and most threatened terrestrial ecoregions.</em> CEMEX, Mexico DF.</p>
<p>Moat, J. (2007) Conservation assessment tools extension for Arc View 3.x, version 1.2. GIS Unit, Royal Botanic Gardens, Kew. Available from: http://www.rbgkew.org.uk/gis/cats (accessed 10 January 2020)</p>
<p>The National Red List (2021)<em> Conservation Status of the Flora of Sri Lanka 2020</em>. Sri Lanka: Biodiversity Secretariat, Ministry of Environment and the National Herbarium, Department of National Botanic Gardens, xviii + 254 pp.</p>
<p>Ruchisansakun, S., Suksathan, P., van der Niet, T., Smets, E.F., Saw-Lwin & Janssens, S.B. (2018) Balsaminaceae of Myanmar. <em>Blumea</em> 63: 199–267. https://doi.org/10.3767/blumea.2018.63.03.01</p>
<p>Trimen, H. (1893) <em>A Handbook to the flora of Ceylon </em>1. Dulau & Co. London.</p>
<p>Thwaites, G.H.K. (1858) <em>Enumeratio Plantarum Zeylaniae</em>. Dulau & Co., London. pp. 65–68.</p>
<p>Yuan, Y.M., Song, Y., Geuten, K., Rahelivololona, E., Wohlhauser, S., Fischer, E., Smets, E. & Küpfer, P. (2004) Phylogeny and biogeography of Balsaminaceae inferred from ITS sequence data. <em>Taxon</em> 53: 391–403. https://doi.org/10.2307/4135617</p>