Begonia capituliformis Irmsch. in Bot. Jahrb. Syst. 50(4): 354. 1913

Primary tabs

https://floramalesiana.org/new/wp-content/uploads/2024/01/SBDP_Bcapituliformis_3_habit_Kinho169.jpg

Begonia Section

  • Petermannia

Habitat

  • Growing terrestrially in hill and upland forests at 600–900 m elevation. (Ardi, W.H. & Thomas, D.C. 2022: Synopsis of Begonia (Begoniaceae) from the northern arm of Sulawesi and Sangihe Island, Indonesia, including three new species. – Edinburgh J. Bot. 79(Begonia special issue, article 405): 1-50. http://doi.org/10.24823/EJB.2022.405)

Conservation

  • Endangered (EN), B1ab(iii)+B2ab(iii). This species is known from only a few collections from secondary forest at the periphery of the Gunung Ambang Nature Reserve, Gunung Lolombulan and Gunung Klabat. The collection localities are in forest patches close to human habitation and surrounded by land used for agricultural purposes (e.g. clove plantations) and other severely disturbed forest vegetation. Exploration of various hill forest localities on Gunung Klabat has not resulted in any additional collections, and therefore we must assume, until more extensive collection efforts reveal otherwise, that this species has a very restricted range. Because of its small extent of occurrence (EOO) (1344 km2) and area of occupancy (AOO) (12 km2), in combination with observed disturbance and loss of forest habitat at the border of the Gunung Lolombulan and Gunung Ambang Nature Reserve, we assess this species as Endangered (IUCN Standards and Petitions Subcommittee, 2019). (Ardi, W.H. & Thomas, D.C. 2022: Synopsis of Begonia (Begoniaceae) from the northern arm of Sulawesi and Sangihe Island, Indonesia, including three new species. – Edinburgh J. Bot. 79(Begonia special issue, article 405): 1-50. http://doi.org/10.24823/EJB.2022.405)
  • Proposed IUCN category: LC. The Sulawesi montane rain forest eco-region is relatively intact and the locality in the G. Klabat reserve is still largely forested from 400 to 2000 m. (Hughes, M. An annotated checklist of Southeast Asian Begonia. 2008)

Distribution

Indonesia: endemic to Sulawesi, North Sulawesi province (eastern North biogeographical region), Gunung Ambang, Gunung Lolombulan and Gunung Klabat
See 'Specimens' tab for map of point distribution data of georeferenced specimens. (Ardi, W.H. & Thomas, D.C. 2022: Synopsis of Begonia (Begoniaceae) from the northern arm of Sulawesi and Sangihe Island, Indonesia, including three new species. – Edinburgh J. Bot. 79(Begonia special issue, article 405): 1-50. http://doi.org/10.24823/EJB.2022.405)

Notes

  • Begonia capituliformis is endemic to the northern arm of Sulawesi. The species is characterised by a dense and strongly compressed subumbellate male inflorescence. This is a unique character among all member of Sulawesi Begonia sect. Petermannia but has some similarity to the inflorescence architecture of B. johntania Ardi & D.C.Thomas from North Konawe, Southeast Sulawesi, which is also in Begonia sect. Petermannia. However, the axis of the male inflorescence of the latter species is less compressed, the pedicels of the female flower are substantially longer, and the fruit are pendulous (Ardi et al., 2018). (Ardi, W.H. & Thomas, D.C. 2022: Synopsis of Begonia (Begoniaceae) from the northern arm of Sulawesi and Sangihe Island, Indonesia, including three new species. – Edinburgh J. Bot. 79(Begonia special issue, article 405): 1-50. http://doi.org/10.24823/EJB.2022.405)

Molecular Systematics

  • GenBank
  • see Thomas et al., 2012 (Thomas, D.C., Hughes, M., Phutthai, T., Ardi, W.H., Rajbhandary, S., Rubite, R., Twyford, A.D. & Richardson, J.E. 2012: West to east dispersal and subsequent rapid diversification of the mega-diverse genus Begonia (Begoniaceae) in the Malesian archipelago. – Journal of Biogeography 39: 98-113)

Specimens

  • SULAWESI: E of Tongoa, Johansson, H. Nybom, S. Riebe 125 (L) [as Begonia capituliformis ?]; Minahassa, G. Klabat, 29 vi 1956, L.L. Forman 314 (K); Minahassa, G. Klabat, 30 vi 1956, L.L. Forman 344A (K); Minahassa, G. Klabat, 30 vi 1956, L.L. Forman 344B (K); SW of Dongala, 11 v 1975, W. Meijer 10093a (L) [as Begonia capituliformis ?]; Minahassa, Bojong, O. Warburg 15190 (holo B; iso B) – Type of Begonia capituliformis Irmsch. (Hughes, M. An annotated checklist of Southeast Asian Begonia. 2008)
  • Indonesia. Sulawesi. Northern arm of Sulawesi. Eastern North Sulawesi: Mount Lolombulan, Above Boyong atas, 24 ii 2008, J. Kinho & A.D. Poulsen 169 (BO, E); Gunung Ambang, 22 ii 2008, M. Ardiyani, A.D. Poulsen & Ale 107 (BO, E); N.E. Celebes, 29 vi 1956, L.L. Forman 314 (K); Wiau Complex, G. Klabat, 30 vi 1956, L.L. Forman 344a,b (K). (Ardi, W.H. & Thomas, D.C. 2022: Synopsis of Begonia (Begoniaceae) from the northern arm of Sulawesi and Sangihe Island, Indonesia, including three new species. – Edinburgh J. Bot. 79(Begonia special issue, article 405): 1-50. http://doi.org/10.24823/EJB.2022.405)