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Card. Bull. Singapore 69(2) 2017 
fringe of fine translucent glandular hairs and glands at the base of the upper lobes, and 
glands and short hairs over the yellow ventral stripe; tube 15-17 mm long dorsally, 
17-21 mm ventrally, 15-19 mm laterally between lips; upper lobes broadly elliptic, 
4.2-5 x 6-7 mm, lateral lobes broadly ovate, 4-9 x 8-9 mm, ventral lobe ovate, 6-9 
x 9-12 mm. Stamens arising 1-1.25 cm above the corolla base, filaments straight, 
white, glabrous, 2-2.5 mm long, 0.4-0.7 mm wide; anthers white or pale yellow, with 
an abundant indumentum of coloured hairs (blue in blue-flowered specimens, brown 
in white-flowered specimens) above and dorsally, 2.3 x 1.3 mm, apically joined by a 
connective, thecae more or less parallel; lateral staminodes 0.6-1.1 mm long, arising 
c. 4.5-8.5 mm above the corolla base, central staminode 0.1-0.7 mm long, arising 
5-8.5 mm above the corolla base. Disk annular, slightly lobed, 0.4-1 mm high. Pistil 
c. 23 mm long; ovary 0.6-1.4 cm long, c. 1 mm diameter, glabrous in the basal 0.5-3 
mm, then densely eglandular hairy; style c. 0.9 cm, sparsely eglandular hairy; stigma 
with a weakly bilobed lower lip, densely hairy, 1-1.6 mm long. Fruit green, brown 
when ripe, 2-3.7 cm long, c. 0.6 mm diameter, eglandular hairy, straight. Seeds brown, 
narrowly elliptic, 0.3-0.4 x c. 0.1 mm. 
Distribution. Eastern and Northeastern Thailand. 
Habitat. On limestone in mixed deciduous forest. 
Provisional IUCN conservation assessment. Endangered EN Blab(iii) + B2ab(iii). 
The known EOO is < 500 km 2 and the known AOO is only 12 km 2 . Not all of the 
known localities are in protected areas and those that are not are subject to disturbance 
from visitors. 
Additional specimens examined. THAILAND: Chaiyaphum: Khon Sarn, Wat Huang Po, 378 
m, 7 Nov 2014, Tetsana, N. et al. 888 (BKF, SING); Khon Sarn, Wat Pa Thum Thep Nimit Doi 
Kitchakoot, 484 m, 12 Sep 2014, Tetsana, N. et al. 834 (BKF, SING). Loei: Nong Hin, Suan Sa 
Wan, PhaNgam Forest Park, 662 m, 11 Sep 2014, Tetsana, N. et al. 824 (BKF, SING). 
Notes. The epithet refers to the narrow corolla tube. Most of the specimens observed 
have pure white corollas, a yellow ventral stripe, and brown anther indumentum. The 
specimen Tetsana, N. et al 834, instead, has a blue-purple corolla, with similarly 
coloured anther indumentum and a yellow ventral stripe. The morphology of the white 
and blue forms are otherwise identical, and no intermediate colour variants have been 
observed. 
The collection from Loei, Tetsana et al. 824, has a longer calyx than the material 
from Loei. Further collections are needed to see whether the Loei material differs 
taxonomically from Microchirita hypocrateriformis. 
11. Microchirita involucrata (Craib) YinZ.Wang, J. Syst. Evol. 49: 60 (2011); Rafidah, 
Gard. Bull. Singapore 69: 15 (2017). - Chirita involucrata Craib, Gard. Chron., Ser. 
3, 83: 140 (1928); Barnett, FI. Siam. 3: 223 (1962); Wood, Notes Roy. Bot. Gard. 
