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The molecular study of Theerakulpisut et al. (2012) supports the classification 
of Zingiber into four sections although Zingiber sect. Zingiber and Zingiber sect. 
Dymczewiczia are only weakly supported. This weak support does not, therefore, 
necessarily refute Theilade’s conclusion that Zingiber sect. Dymczewiczia should be 
included in Zingiber sect. Zingiber. These two sections are more closely related to each 
other than to Zingiber sect. Cryptanthium and Zingiber sect. Pleuranthesis Benth. & 
Hook. (Theerakulpisut et al., 2012). 
Plants of an unidentified Zingiber were collected from limestone at Bantimurung, 
South Sulawesi in 2009. When they were first encountered, several individuals could 
be seen from the road but they were not easy to reach. At first the sterile plants were 
thought to be a species of Globba L. different from the only other species known to 
occur east of Wallace’s Line, G. marantina L. As this would be a biogeographically 
exciting discovery, we decided to try to collect sterile plants for cultivation. Despite 
some difficulty because the roots were deeply anchored in cracks in the limestone, 
we managed to collect 10 plantlets that were exported to Java, half of which were 
deposited in Bogor Botanic Gardens and the other half in the Royal Botanic Garden 
Edinburgh (accession numbers 20092015-20092019). Some of the plants flowered in 
Edinburgh, enabling us to conclude that it is an undescribed species which we here 
name Zingiber ultralimitale, and to make a full description including floral details and 
pollen morphology. In addition to describing this species formally, we investigate the 
sectional placement of this geographically unusual find using palynological data and 
molecular systematic analyses. 
Table 1. Sections of Zingiber with their characteristics and geographical distribution (Baker 
1894; Schumann 1904; Theerakulpisut et al. 2012). 
Section 
Geography 
Inflorescence 
Pollen morphology 
Zingiber 
India, China, Indo- 
China, Thailand, 
Peninsular Malaysia, 
Sumatra, Borneo, Java, 
Cultivated 
Borne on radical, erect 
peduncle or borne 
apically on a leafy stem 
Spherical with cerebroid 
exine sculpturing 
Cryptanthium 
India, Thailand, China, 
Indo-China 
Borne on a radical, 
procumbent peduncle 
Ellipsoidal with spiro-striate 
sculpturing 
Dymczewiczia 
India, China, Indo- 
China, Thailand, Java, 
Papua New Guinea 
Borne apically on a 
leafy stem 
Spherical with cerebroid 
exine sculpturing 
Pleuranthesis 
China (Yunnan), 
Vietnam 
Arising from the side of 
the leafy stem 
Spherical with cerebroid 
exine sculpturing 
