Khoonmengia N.H.Xia, Y.H.Tong & X.R.Zheng, 2020

Tong, Yi-Hua, Zheng, Xi-Rong, Zhang, You Yuan, Qin, Qiao-Mei, Ni, Jing-Bo, Vu, Tien Chinh & Xia, Nian-He, 2020, Khoonmengia honbaensis, a new genus and species of temperate bamboo (Poaceae, Bambusoideae) from central-southern Vietnam, PhytoKeys 138, pp. 163-177 : 163

Khoonmengia N.H.Xia, Y.H.Tong & X.R.Zheng gen. nov.

Type.

Khoonmengia honbaensis N.H.Xia, Y.H.Tong & X.R.Zheng.

Diagnosis.

Khoonmengia resembles Hsuehochloa and Ampelocalamus in having pachymorph and short-necked rhizomes, florets with 3 stamens and 2 stigmas, but differs from the former by its scrambling habit, nodes swollen at one side, mid-culm branch complement with one central dominant branch elongating to reiterate the culm accompanied by 1-4 lateral slender branches, swollen culm sheath base with a distinctive zone of transverse wrinkles, culm and leaf sheaths without auricle or oral setae, and single or several to many synflorescences arranged into a raceme or panicle, and can be distinguished from the latter by extravaginal branching pattern, buds wholly sunken into culm, culm sheath base with a distinctive zone of transverse wrinkles, synflorescence composed of only one spikelet, purple anthers and nut-like caryopsis with hardened pericarp and loosely adherent lemma and palea.

Description.

Shrubby bamboo. Rhizomes pachymorph, short-necked. Culms unicaespitose, erect at lower part, distally scrambling; internodes terete, with dense brownish green dots; nodes conspicuous, swollen at one side. Buds elliptic, wholly sunken into culm. Branches extravaginal, often solitary at lower part of culm, and usually with one central dominant branch elongating to reiterate the culm and 1-4 lateral slender ones in the middle part of culm. Culm sheaths persistent, basally swollen, with a distinctive zone of transverse wrinkles; auricles and oral setae absent; blade reflexed; ligule convex. Foliage leaves without auricles and oral setae; ligules convex. Synflorescence semelauctant, composed of only one spikelet subtended by one or several sheath-like bracts, single or several to many synflorescences arranged into a raceme or panicle which is terminal on leafy branches; spikelets with 8-9 florets. Glumes (0-)1-2. Palea slightly shorter than lemma. Lodicules 3. Stamens 3, filaments free, anthers purple. Styles 2, free, stigmas 2, plumose. Caryopsis nut-like, with a hardened pericarp and loosely adherent lemma and palea, apex with 2 persistent style bases.