Research Paper

New Begonia species from Ilin Island, Occidental Mindoro Province, Philippines and insights to the coastal species of Begonia sect. Baryandra

Mark Angelo C. Bucay, Danilo N. Tandang, Mikko Angelo G. Reyes, Neil Anthony A. Del Mundo, Kuo-Fang Chung

Published on: 06 January 2026

Page: 42 - 48

DOI: 10.6165/tai.2026.71.42

  • BibTeX
    •
  • EndNote
    •
  • RIS
    •

    Abstract

    Begonia ilinensis is a newly described species of Begonia sect. Baryandra, first found in the coastal areas of Ilin Island, off the southwestern coasts of Mindoro Island in the Philippines. The species resides in exposed to semi-exposed limestone areas on the coast. The species is notable for its dormancy during the dry months, where it is limited to its minute rhizomes. It only starts growing its foliage and flowers during the wet season of June to November. Morphologically, the species is relatively small compared to most Baryandra species in the Philippines, but resembles Begonia luzonensis, a resident of nearby Luzon Island, mainly by its leaf margins. However, the species is much smaller compared to B. luzonensis specifically in terms of lamina, inflorescences, and capsules, and it lacks the characteristic rusty villous indumentum of B. luzonensis on its leaves, peduncles, and petioles. We also documented and mapped other Begonia sect. Baryandra that we have found thriving on the same habitat as B. ilinensis on other portions of the Philippines to shed further insights on the ecology of these coastal Begonias based on their habitat preferences.

    Keyword: archipelago, Begonia ilinensis, Begonia luzonensis, biogeography, karst ecosystems, species radiation

    Literature Cited

    Bachman, S., Moat, J., Hill, A., de Torre, J., Scott, B. 2011 Supporting red list threat assessments with GeoCAT: geospatial conservation assessment tool. ZooKeys 150: 117–126.
    DOI: 10.3897/zookeys.150.2109View Article Google Scholar

    Blasco, F.A., Alejandro, G.J.D., Tandang, D.N., Vales, M.B., Rubite, R.R. 2022 Begonia amparoi (Begoniaceae, section Baryandra) a new species from Linungaw Twin Islands, Surigao del Sur, Mindanao, Philippines. Phytotaxa 549(2): 136–140.
    DOI: 10.11646/phytotaxa.549.2.2View Article Google Scholar

    Bucay, M. A. C., D. N. Tandang, H.-W. Chen, L.-W. Tsai, R. R. Rubite, Chung, K.-F. 2025 Morphological and molecular analyses revealed two new species of Begonia sect. Baryandra in the Eastern Mindanao Biodiversity Corridor, Philippines. Phytotaxa 698(4): 245–256.
    DOI: 10.11646/phytotaxa.698.4.4View Article Google Scholar

    Calaramo, M.A., Rubite, R.R., Pugal, C.M., Lin, C.-W. 2019. New species of Begonia section Baryandra (Begoniaceae) from Northwestern Luzon, Philippines. Phytotaxa 407(1): 36–42.
    DOI: 10.11646/phytotaxa.407.1.6View Article Google Scholar

    Custodio, C.C., Lepiten, M. V., Heaney, L. R. 1996 Bubalus mindorensis. Mammalian species 520: 1–5.
    DOI: 10.2307/3504276View Article Google Scholar

    Elmer, A.D.E. 1910 New species of Begonia. Leafl. Philipp. Bot. 2: 735–740.

    Elmer, A.D.E. 1915 Two hundred twenty-six new species -I. Leafl. Philipp. Bot. 7: 2543–2703.

    Espeja, B.L., Bucay, M.A.C., Tandang, D.N., Rubite, R.R., Chen, H.-W., Chung, K.-F., Bautista, M.G. 2024 A new record of Begonia aptera in Southern Mindanao: the second species of Begonia sect. Platycentrum recorded from the Philippines. Phytotaxa 670(3): 181–186.
    DOI: 10.11646/phytotaxa.670.3.4View Article Google Scholar

    Delos Angeles, M.D., Rubite, R.R., Chung, K.-F., Buot Jr., I.E., Tandang, D.N. 2022 Begonia normaaguilariae (section Baryandra, Begoniaceae), a new species from the limestone forests of Samar Island, Philippines. Phytotaxa 541(1): 49–56
    DOI: 10.11646/phytotaxa.541.1.4View Article Google Scholar

    Hughes, M., Peng, C.-I., Lin, C.-W., Rubite, R.R., Blanc, P., Chung, K.-F. 2018 Chloroplast and nuclear DNA exchanges among Begonia sect. Baryandra species (Begoniaceae) from Palawan Island, Philippines, and descriptions of five new species. PLoS ONE 13(5): e0194877.
    DOI: 10.1371/journal.pone.0194877View Article Google Scholar

    Hughes, M., Coyle, C., Rubite, R.R. 2010 A Revision of Begonia section Diploclinium (Begoniaceae) on the Philippine Island of Palawan, including five new species. Edinb. J. Bot. 67(1):123–140.
    DOI: 10.1017/S0960428609990266View Article Google Scholar

    Hughes, M., Rubite, R. R., Blanc, P., Chung, K. F., Peng, C. I. 2015 The Miocene to Pleistocene colonization of the Philippine Archipelago by Begonia sect. Baryandra (Begoniaceae). Am. J. Bot. 102(5): 695–706.
    DOI: 10.3732/ajb.1400428View Article Google Scholar

    Merrill, E.D. 1908 On a collection of plants from Batanes and Babuyanes island. Philipp. J. Sci., Sect. C 3(6): 385–442.

    Merrill, E.D. 1912 [1911] The Philippine species of Begonia. Philipp. J. Sci., Sect. C 6(6): 369–406.

    Merrill, E.D. 1918 New or noteworthy Philippine Plants XIII. Philipp. J. Sci., Sect. C 13: 1–66.

    Merrill, E.D. 1925 Additions to our knowledge of the Philippine flora I. Philipp. J. Sci., Sect. C 26: 447–496.

    Merrill, E.D., Quisimbing, E. 1932 Begonia wadei. Addisonia 17: 57–58.

    Moonlight, P.W., Ardi, W.H., Padilla, L.A., Chung, K., Fuller, D., Girmansyah, D., Hollands, R., Jara-Mu?oz, A., Kiew, R., Leong, W., Liu, Y., Mahardika, A., Marasinghe, L.D.K., O’Connor, M., Peng, C., P?rez, ?.J., Phutthai, T., Pullan, M., Rajbhandary, S., Reynel, C., Rubite, R.R., Sang, J., Scherberich, D., Shui, Y., Tebbitt, M.C., Thomas, D.C., Wilson, H.P., Zaini, N.H., Hughes, M. 2018 Dividing and conquering the fastest–growing genus: Towards a natural sectional classification of the mega–diverse genus Begonia (Begoniaceae). Taxon 67(2): 267–323.
    DOI: 10.12705/672.3View Article Google Scholar

    Pelser, P.B., Barcelona J.F., Nickrent, D.L. (eds.). 2011 onwards. Co's Digital Flora of the Philippines. Online database available from: www.philippineplants.org

    Rubite, R. R., Justo, C. A. D., Villasenor, P. C., Delos Angeles, M. D., Tandang, D. N., Lin, C. W. 2021 Three new species of Begonia (section Baryandra, Begoniaceae) from Samar Island, the Philippines. Phytotaxa 516(3): 263–274.
    DOI: 10.11646/phytotaxa.516.3.5View Article Google Scholar

    Rubite, R.R., Hughes, M., Alejandro, G.J., Peng, C.-I. 2013 Recircumscription of Begonia sect. Baryandra (Begoniaceae): evidence from molecular data. Bot. Stud. 54(38): 1–5.
    DOI: 10.1186/1999-3110-54-38View Article Google Scholar

    Sarewitz, D.R., Karig, D.E. 1986 Process of allochthonous terrane evolution, Mindoro island, Philippines. Tectonics 5(4): 525–552.
    DOI: 10.1029/TC005i004p00525View Article Google Scholar