252 
Card. Bull. Singapore 69(2) 2017 
hairs, inside glabrous except at the tip, margin ciliate at the tip. Corolla c. 35 mm long, 
tube white at the base, turning pale yellow distally, base of ventral lobe with a yellow 
stripe, lobes pale yellow at the base, paler towards the margin, tube narrow at the base, 
curved basally and gradually broadening, mouth broad and slightly gibbous laterally 
and ventrally, base of the tube, upper lobes and ventral lobe glabrous, the rest of the 
corolla externally covered in short mixed glandular and eglandular hairs, internally 
with sparse glandular hairs, forming a denser patch at the base of the upper lobes, lobes 
slightly papillose; tube c. 23 mm long dorsally, c. 27.5 mm ventrally, c. 24 mm laterally 
between lips; lobes broadly elliptic, upper lobes c. 5.5 x 10 mm, lateral lobes c. 6 x 
8.5 mm, ventral lobe c. 8.5 x 10.5 mm. Stamens arising c. 17 mm above the corolla 
base, filaments strongly geniculate, with a basal, thinner segment c. 2 x 0.7 mm, and 
an apical, thicker segment c. 4.5 x 1.6 mm, pale yellow, glabrous; anthers white, with 
white hairs dorsally, c. 3.5 x 2.5 mm, apically joined by a connective, thecae parallel or 
slightly divergent; lateral staminodes c. 0.7 mm long, arising c. 9 mm above the corolla 
base, central staminode c. 0.5 mm long, arising c. 9 mm above the corolla base. Disk 
annular, margin entire, 1 mm high, c. 0.5 mm thick (exceptionally thick). Pistil c. 29 
mm long; ovary c. 10 mm long, c. 1.6 mm diameter, lower 1/3 glabrous, then densely 
tomentose with eglandular and perhaps glandular hairs; style c. 18 mm long, with the 
same indumentum as ovary; stigma bilobed, lobes elliptic, 1 mm. Fruit green, 7-10.5 
cm long, 0.5-2.5 mm diameter, densely hairy, straight or slightly curved. Seeds light 
brown, narrowly elliptic, with irregular surface, 0.3 x 0.1 mm. 
Distribution. Northeastern Thailand. 
Habitat. On limestone in evergreen forest. 
Provisional IUCN conservation assessment. Endangered EN B2ab(iii). This species 
has an AOO of around 20 km 2 and is only known from a small number of collections, 
not all of which are in protected areas. 
Additional specimens examined. THAILAND: Kalasin: Somdat, Pu Parn, 24 Oct 1975, 
Sutharson, S. & Sangkhachand, P. 3450 (BKF). Loei: Nong Hin, Ban Puen Phue, c. 640 m, 22 
Sep 2007, Thitimetharoch, T. et al. 797 (BKF); Phu Luang, 22 Aug 1966, Phusomsaeng, S. & 
Bunchuai, K. 11 (BKF, K, L); Phu Krading, Sam Khae, c. 1050 m, 16 Oct 1954, Smitinand, T. 
2026 (BKF). 
Notes. This species is named after its pale yellow corolla. 
16. Microchirita marcanii (Craib) A.Weber & D.J.Middleton, Taxon 60: 778 (2011). 
- Chirita marcanii Craib, Bull. Misc. Inform. Kew 171 (1926); Barnett, FI. Siam. 
3: 226 (1962); Wood, Notes Roy. Bot. Gard. Edinburgh 33: 193 (1974); Burtt, Thai 
Forest Bull., Bot. 29: 88 (2001). - TYPE: Thailand, Saraburi, Muak Lek, c. 250 m, 
10 November 1924, Marcan 1872 (lectotype ABD, designated by Wood (1974: 193); 
isolectotypes K (2)). (Fig. 11D-F) 
