大花哥纳香 da hua ge na xiang

Trees to 8 m tall. Branchlets pubescent, glabrescent. Petiole 0.7-1.5 cm, robust; leaf blade oblong, 17-35 × 5.5-9 cm, papery, glabrous, midvein stout and adaxially depressed, secondary veins 14-20 on each side of midvein and slightly elevated on both surfaces, base rounded to broadly cuneate, apex obtuse to shortly acuminate. Inflorescences axillary or extra-axillary, 1-flowered. Pedicel 1-1.5 cm, glabrous, many bracteolate at base. Sepals broadly ovate, 2-2.5 cm, glabrous. Outer petals oblong-lanceolate, 5-6.5 × ca. 1.5 cm, puberulent; inner petals oblong-ovate, ca. 2 × 0.8 cm, puberulent. Stamens oblong, ca. 4 mm; connectives 3-angular. Carpels cylindric, ca. 6 mm, pubescent; ovules 2 per carpel; styles elongate; stigmas apically 2-cleft. Monocarps fasciculate, subsessile, ovoid, ca. 1.5 × 0.8 cm, puberulent. Seed 1 per monocarp. Fl. Apr-Aug, fr. Aug-Nov.

Forested slopes; 800-1500 m. S Yunnan [N Thailand].

Saunders and Chalermglin (Bot. J. Linn. Soc. 156: 359-363. 2008) regard the Chinese material identified as Goniothalamus griffithii J. D. Hooker & Thomson to be more correctly placed in G. calvicarpus, treating G. griffithii as a local species restricted to S Myanmar and adjacent W Thailand. The Chinese material is somewhat intermediate between the two, and clearly the situation needs more detailed investigation.