222 
Card. Bull. Singapore 69(2) 2017 
tube 17-19 mm long dorsally, 18-22 mm ventrally, 16-20 mm laterally between lips; 
lobes elliptic, upper lobes 2.5-3.7 x 5-6.5 mm, lateral lobes 4.5-5 x 5-7.5 mm, ventral 
lobe 4.5-5 x 4.5-7 mm. Stamens arising 8.5-9 mm above the corolla base; filaments 
geniculate, yellow, glabrous, 2-3 mm long, 0.5-0.6 mm wide; anthers white, with a 
woolly orange indumentum dorsally and at base, and short appressed orange hairs 
around the apex, c. 1.5-2 x 3 mm, apically coherent and joined by a short ligature, 
thecae divergent; lateral staminodes 1.5-3 mm long, arising 6-7 mm above the corolla 
base, central staminode 0.3-0.5 mm long, arising c. 6 mm above the corolla base. Disk 
annular, margin entire or cleft dorsally, 0.1-0.4 mm high. Pistil (immature) 15-17 
mm long; ovary 8-9 mm long, 1.2-1.7 mm diameter, glabrous around the base, then 
densely eglandular hairy; style c. 4 mm long, eglandular hairy, more sparsely towards 
the stigma; stigma bilobed, lobes elliptic, 0.5-2 x 0.5 mm. Fruit green, 2.3-5 cm long, 
1-1.7 mm diameter, eglandular hairy, straight or slightly curved. Seeds light brown, 
narrowly elliptic, tri-tetrangular, mucronate, 0.2-0.5 x 0.1-0.5 mm. 
Distribution. Northeastern Thailand (Loei). 
Habitat. On limestone, in shade. 
Provisional IUCN conservation assessment. Critically Endangered CR Blab(iii). 
Although only known from a single collection the plant was collected from a limestone 
outcrop which has a total potential area suitable for the growth of Microchirita species 
of around 14 km 2 and which is not in a protected area. There has been development 
within the limestone range and agricultural land encroaches right to the base of the 
outcrop with the potential for changes in microclimate. 
Notes. The epithet refers to the colour of the corolla tube and lobes. 
3. Microchirita aratriformis (D.Wood) A.Weber & D.J.Middleton, Taxon 60: 778 
(2011). - Chirita aratriformis D.Wood, Notes Roy. Bot. Gard. Edinburgh 31: 367 
(1972); Wood, Notes Roy. Bot. Gard. Edinburgh 33: 197 (1974); Burtt, Thai Forest 
Bull., Bot. 29: 87 (2001). - TYPE: [Vietnam], Tonkin, Langson, Khanmoi, Eberhardt 
3332 (holotype P [P00602506]). (Fig. 3A-B) 
Caulescent herb to 60 cm tall, branching, internodes to c. 7 cm. Stem green, 
slightly fleshy, with a mixed indumentum of glandular and eglandular hairs. Leaves 
opposite except for the basal leaf; petioles 0.5-3 cm long, eglandular hairy; blades 
green above, paler beneath, lanceolate to elliptic, 4.8-10(-13+) x 2.5-10 cm, 1.6- 
2.1 times as long as wide, base acute to shortly acute or subcordate, apex acute to 
acuminate, sparsely eglandular hispid above and beneath, margin entire, 8-14+ pairs 
of secondary veins (basal leaf not seen), tertiary venation not visible. Inflorescences 
cristate, 4-10-flowered; peduncles 1-17 mm long, fused with each other, eglandular 
hairy; bracts absent; pedicels 15—20(—31 reported in literature) mm long, glandular 
