Begonia ignita, a new species from Sulawesi 
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at base; anthers c. 0.8 mm long, oblongoid, subequal in length to filaments. Pistillate 
flower: pedicel 6-13 mm long, glabrous; tepals 4 (rarely 2, 3 or 5), pale orange to 
vermilion, ovate or obovate to oblanceolate, 9-15 mm long, 4-10 mm wide, glabrous; 
ovary reddish, body trigonous-ellipsoid, 9-11 mm long, c. 7 mm across, 3-winged; 
wings cuneate or rounded at base, truncate or rounded at the apex, 12-15 mm long, 
2-4 mm wide, locules 3, placentae axile, bilamellate; styles 3, yellow, bifid, c. 4 mm 
long; stigmas in a spiral band and papillose all around. Fruits not seen. 
Distribution. Only known from cultivation; likely endemic to Sulawesi (see Notes). 
Etymology. The specific epithet refers to the flame-coloured tepals (Latin: igneus - 
flame-coloured). 
Notes. Begonia ignita has entered into cultivation and is grown by various amateur 
enthusiasts and Begonia collectors inside and outside of Indonesia. The origin of 
these cultivated plants remains obscure. Enquiries about the species’ origin with 
several growers indicated that most acquired the plants from material cultivated 
by other growers. This is also the case for the plants cultivated at Bogor Botanic 
Gardens on which the description is based. Some growers indicated that a market in 
Sulawesi was the likely original source of the plants, but they could not provide any 
additional information on the location of this market (province, city etc.). Phylogenetic 
reconstructions using chloroplast DNA sequence data of Begonia ignita (ndhA intron, 
ndhF-rpl32 spacer, rpl32-trnh spacer, unpublished data, D. Thomas) integrated with 
previously published data of other Asian taxa (Thomas et al., 2012; Moonlight et 
al., 2015), including accessions of about 74% of the currently accepted species from 
Sulawesi, corroborate a putative Sulawesi origin. Begonia ignita is retrieved in a well- 
supported clade of Sulawesi endemics in Begonia section Petermannia. It is sister 
to a well-supported clade including two subclades: a subclade of endemic species 
distributed on the northern arm of Sulawesi, and a subclade of species endemic to 
eastern Central Sulawesi. 
Begonia ignita is one of the most distinct and most beautiful Indonesian species 
in cultivation. Its colourful cordiform leaves adorned with a silvery green band or 
maculation ru nnin g inside the margin, and the showy flammate flowers immediately 
make it a very attractive species. It is distinct from all other Sulawesi begonias by the 
symmetric or subsymmetric cordiform leaves and in being the only known orange- 
flowered Begonia on the island. The new species resembles the Sulawesi endemic 
Begonia mendumiae M.Hughes (sect. Petermannia ) in the creeping habit, and the 
band or maculation of the leaves but can be easily differentiated from B. mendumiae 
by the characters shown in Table 1. 
