Allium pseudosenescens H.J.Choi & B.U.Oh

  • Authority

    Choi, Hyeok-Jae & Oh, Byoung-Un. 2010. A new species and a new combination of Allium sect. Rhizirideum (Alliaceae) fromnortheastern China and Korea. Brittonia. 62 (3): 199-205.

  • Family

    Amaryllidaceae

  • Scientific Name

    Allium pseudosenescens H.J.Choi & B.U.Oh

  • Description

    Description - Perennial herbs. Rhizomes well-developed and elongated, horizontal and branched, 16- 52.8 mm long. Bulbs clustered, cylindric- conical, without bulblets, 12-20 mm in diam.; tunics membranous, smooth, white. Leaves 4- 10; leaf sheaths slightly exposed over ground, 4-8 cm high, non-striped; leaf blades ascend- ing, slightly tortuous, linear, flat, fleshy, 23- 45 cm long, 5-15 mm wide, solid and with 2-rowed vascular bundles in cross-section, sessile at base, obtuse to rounded at apex. Scapes sometimes lateral from the bulbs, not slender, subterete to rhomboid, drooping before flowering, solid in cross-section, 25.8- 70 cm long, 3-5.5 mm wide. Inflorescences umbellate, subglobose, 30-60 mm high, 40- 60 mm wide, without bulblets, 31-120 flowered; pedicels terete, equal in length, 10-32 mm long, thinner than the scapes, slender; bracts 4.8-6.5 mm long. Flowers bisexual; perianth radially spreading, pale pink; inner tepals longer than outer ones, elliptical, obtuse at apex, 6-6.8 mm long, 2.5-3 mm wide; outer tepals ovate-elliptical, obtuse at apex, 4.5- 5.5 mm long, 2-2.7 mm wide; filaments long exserted, subulate, 7-11 mm long, entire or 2- toothed (middle of inner ones) at margin; anthers elliptical, yellowish, 1.9-2 .1 mm long; ovary obovoid, reddish, without hood-like projections at base, 3.2^4 mm long, 2.2- 2.6 mm wide, ovules 2 per locule; style terete, exserted; stigma smooth. Capsules cordiform, trigonous, 4.5-5.5 mm long, 4.5-5.6 mm wide. Seeds oval, semi-circular in cross-section, 3- 3.5 mm long, 2.2-2.4 mm wide. Chromosome number 2n=Ax=32.

  • Discussion

    Distribution and ecology. - The distribution of A. pseudosenescens is somewhat limited. So far, it has been found only in the northern region of Heilongjiang, China, in open meadows and on arid slopes. Because of its restricted distribution, this new species is thought to be endemic to China.

    Phenology. - Flowering from July to September.

    Etymology. - The specific epithet is given considering its similarity with A. senescens.

    Allium pseudosenescens had been identified as A. senescens in various Chinese herbaria (Choi & Oh, pers. obs.), but the former is easily distinguished by its slender pedicels, pale pink perianths, narrower tepals and ovaries, yellowish anthers, and sometimes toothed subulate filaments (Table I; Figs. 1, 2 and 3A-D). Allium senescens is widely distributed from Europe to central Korea. In addition, phylogenetic analysis of nrITS sequence data indicates that A. pseudosenescens is genetically distinct from the other northeastern Chinese and Korean species in sect. Rhizirideum (Choi, 2009).