Begonia balgooyi D.C.Thomas & Ardi

Ardi, Wisnu H., Chikmawati, Tatik, Witono, Joko R. & Thomas, Daniel C., 2018, A synopsis of Begonia (Begoniaceae) of Southeastern Sulawesi including four new species, Phytotaxa 381 (1), pp. 27-50 : 31

2. Begonia balgooyi D.C.Thomas & Ardi in Thomas et al. (2018: 162) ( Figures 1 & 3 )

Sect. Petermannia

Type:— INDONESIA. Sulawesi, Southeast Sulawesi: Kolaka District, Mangolo Forest Reserve , 68 m, 3 February 2017, W.H. Ardi 133 (holotype BO!; isotypes KRB!, SING!) .

Distribution:— Indonesia; endemic to Sulawesi, Southeast Sulawesi. Known from only three localities: Mangolo Nature Recreation Park, Mt. Watuwila, and the Matarombeo mountain range.

Habitat:— On steep slopes or river embankments in lowland and upland rainforest, in dense shade, on limestone soils, at ca. 50–1200 m elevation.

Provisional IUCN conservation assessment:— Endangered EN B1ab(iii),B2ab(iii) (see Thomas et al., 2008).

Notes: ─ Begonia balgooyi is distinct in Begonia section Petermannia on account of its palmately compound leaves, and it can easily be differentiated from the other two palmately compound-leaved species in the section from Sulawesi: Begonia insueta D.C. Thomas & Ardi [2011: 230] is a much more robust plant and has characteristic fruits with much longer pedicels (to 19 mm long) and unequal wings; B. rachmatii Tebbitt (2005: 101) has many-flowered cymoseracemose male inflorescences composed of multiple monochasial partial inflorescences, 15–30 stamens per male flower, and subsessile fruits (pedicels 1–2 mm), while B. balgooyi has male inflorescences comprised of single fewflowered monochasia, male flowers with 46–50 stamens, and longer fruit pedicels (to 9 mm long) ( Thomas et al. 2018). In its growth habit and inflorescence morphology, Begonia balgooyi is closest to the simple-leaved Begonia flacca .

Additional specimens examined: ─ INDONESIA. Southeast Sulawesi: Tawanga, B. Watuwila, ca. 1200 m, 24 Mar. 1929, Kjellberg 1010 ( BO) ; N of Linomoyo, Mt. Matarombeo, Anoa forest , 86 m, 15 Feb. 2017, W.H. Ardi WI 157 ( BO, KRB, SING) .

Figures

FIGURE 1. Distribution map.A. Overview of Sulawesi. B. Distributions of B. aptera, B. johntania, B. mekonggensis, and B. ozotothrix.C. Distributions of B. balgooyi, B.flacca, B. matarombeoensis, and B. watuwilensis. D. Distributions of B.incudiformicarpa, B. iskandariana, and B. tumburanoensis. Specimen location information was georeferenced using the GeoNames geographical database at http://www. geonames.org/.

FIGURE 3. Begonia balgooyi. A. Habit; scale bar: 10 cm. B.Adaxial leaf lamina and petiole; scale bar: 5 cm. C. Stipule; scale bar: 5 mm. D. Male inflorescence (monochasium); scale bar: 15 mm. E. Male flower; scale bar: 10 mm. F. Female flower, front view; scale bar: 10 mm. G. Female flowers, side view; scale bar: 5 mm. H-I. Fruit, front view; scale bar: 5 mm. J. Ovary, cross-section of middle part; scale bar: 3 mm.A, B, A–F, H, I from Ardi, W.H. 133; C, G, J from Ardi, W.H. 157. (Photos: W.H. Ardi).