Kengyilia guidenensis (Poaceae: Triticeae), a New Species from Western China

Abstract

Kengyilia guidenensis, a new species from western China, is described and illustrated. Cytological observations are provided, and comparisons with similar species are made. During an expedition to western China, a new species of Kengyilia was found. It was growing on a mountain slope close to the highway from Guide to Guomaying, between the 150 and 151 Km road poles. When collected it was identified as K. nana J. L. Yang, Yen & Baum; however, the habitat of K. nana is alpine steppes above 4000 m, whereas the Guide population was found just below 3100 m altitude and in stony slopes. The habitat of the Guide population is similar to that of K. kokonorica (Keng) J. L. Yang, Yen & Baum, but differs by being dwarf in appearance and by having ovate, dense, small spikes. In the same site another species of Kengyilia was found. This was K. mutica (Keng ex Keng & S. L. Chen) J. L. Yang, Yen & Baum, from which it readily differs in gross morphology by its dwarf habit and by its short ovate spike with long lemma awn. Kengyilia mutica does not have awns, and its spike is long and cylindrical. These preliminary observations led to the suspicion that a new species was on hand. The purpose of the present paper is to describe this species and to detail differences from the species most similar to it. MATERIALS AND METHODS Herbarium specimens and seeds were collected in 1993 in Guide County, Qinghai Province, China, and compared with specimens of Kengyilia nana and K. kokonorica (including their types) in N and SAUTI. Cytological observations were made using the methods detailed in Yen and Yang (1990). DESCRIPTION Kengyilia guidenensis Yen, J. L. Yang & Baum, sp. nov. TYPE: China. Qinghai Province: Guide County, Guide to Guomaying highway between markers 150 and 151 Km, alt. 3100 m, 35089'N, 100026'E, 11 Sep. 1993, C. Yen, J. L. Yang & G. L. Sun 930001 (holotype, SAUTI; isotype, DAO). Figure 1. Kengyiliae kokonoricae (Keng) J. L. Yang, Yen & Baum affinis, sed laminis superioribus albo-villosis; spicis brevioribus, 3-3.5 cm, et angustioribus, 5 mm; spiculis brevioribus, 7 mm, et plurifloribus, 5-7; glumis longioribus, 4-7 mm, lanceolatis; aristis lemmatum brevioribus, 1.54 mm; carinis palearum ominino ciliatis; antheris longioribus, 3 mm, differt. Kengyiliae nanae J. L. Yang, Yen & Baum affinis, sed culmis longioribus, 35-50 cm longis; foliorum vaginis glabris, laminis longioribus, 8.5-9 cm longis; spicis angustioribus, 5 mm latis; glumis lanceolatis; aristis lemmatum brevioribus, 1.5-4 mm longis; paleis ominino ciliatis differt. Caespitose perennial, with fibrous roots (Fig. lA). Culms caespitose, erect, 35-50 cm tall, 1.5 mm diam., 2-3-noded, pubescent just below the spike for 1-3 cm, geniculate at the base. Leaf sheaths glabrous, rarely pubescent in the lowermost sheaths; ligules scarious, membranous, truncate, premorse, ca. 0.5 mm long; leaf blades flat or slightly involute, narrowly lanceolate, 8.5-9 cm long, 3 mm wide, their adaxial surface with dense 1-mm-long white hairs emerging from the lateral nerves, their abaxial surface glabrous; leaf blades of the tillers densely pubescent, up to 12 cm long. Spikes erect, short and dense, ovate, 3-3.5 cm long, 5 mm wide; rachis internodes 1.5-2 mm long, densely white-pilose; spikelets oblong-ovate (Fig. 1J), greenish purple, with 5-7 florets 7 mm long (excluding awns); rachilla internodes 1-1.2 mm long, densely hirtulous; glumes unequal, wide lanceolate, w th herbaceous membranous margins (Fig. 1B, C), 1(-3)-nerved, with midrib pronounced and NOVON 5: 395-397. 1995. This content downloaded from 157.55.39.156 on Wed, 14 Jun 2017 18:06:19 UTC All use subject to http://about.jstor.org/terms