Yersinochloanianheana (Poaceae, Bambusoideae), a new species from southern Vietnam

Abstract

Yersinochloanianheana sp. nov. from Vietnam is described and illustrated. It is found in southern Vietnam, where it occurs at an elevation of 1400-1500 m in Voi Mountain, Duc Trong District, Lam Dong Province. This new species is distinguished from a similar species, Yersinochloadalatensis, by culm nodes with a thick swollen patella, culm leaf blades erect, auricles conspicuous, margins bearing long hairs, palea dorsal view showing rachilla extension and rudimentary floret at the apex and lodicules purple gradually towards the top. Besides that, the species is distinguished from Yersinochloanghiana by the leaf blades without being swollen at the base, the prophyllate bud 2-keeled, lodicules purple at ½ upper parts and unbifid at the base.

Keywords: Bambusoideae; morphology; new taxon; pseudo-spikelet.

Figure 1.

Yersinochloanianheana V.T.Tran, N.V.Duy & T.V.Tran A habitat B clump C node D shoots E, F culm leaves G auricles H culm leaf I ligule J bud K leafy branch L, M section of a leafy branch N several branches with middle one dominant. Photos by Tran Thai Vinh from the type locality.

Figure 2.

Yersinochloanianheana V.T.Tran, N.V.Duy & T.V.Tran A, B, C inflorescence terminating at leafy branches D, E pseudo-spikelets F perfect florets G rachilla internode H prophyllate bud 2-keeled I glume J lemma K palea with rachilla extension L lodicules M stamens and pistil N anther apiece bearing tiny spines O young fruit P stigmas Q mature fruit. Photos by Tran Thai Vinh from the type locality.

Figure 3.

Yersinochloanianheana V.T.Tran, N.V.Duy & T.V.Tran, Y.dalatensis H.N.Nguyen & V.T.Tran and Yersinochloanghiana V.T.Tran & T.V.Tran A1 bud A2 culm sheath A3 prophyll A4 lodicules B1 bud B2 culm sheath B3 prophyll B4 lodicules C1 bud C2 culm sheath C3 prophyll C4 lodicules. Photos by Tran Thai Vinh from the type locality.