Corispermum nanum Sukhor. & M. Zhang, 2014

Sukhorukov, Alexander P., Zhang, Mingli & Nilova, Maya V., 2014, The carpology and taxonomy of some Chinese Corispermum (Amaranthaceae s. l.), Phytotaxa 172 (2), pp. 81-93 : 84-85

Corispermum nanum Sukhor. & M. Zhang , sp. nov.

Type: — CHINA. Xizang [Tibet], Saga, Nyalam road, 17 August 2011, Yu, Hou & Zhang 5607 (holotype PE-2264191!) ( Fig. 4) .

Diagnosis: —Dwarfish, densely pubescent annual up to 6 cm with single stem or with short lateral branches. Leaves linear, to 2 mm wide. Inflorescence very short producing a few flowers with a perianth consisting of one segment. Bracts slightly shorter than fruits (the fruit margins are visible). Fruit ovoid, 2.5–2.7 × 2 mm, glabrous, apex with two-fid tip, no visible detachments of the pericarp from the seed coat, marginal wing conspicuous (0.3–0.4 mm) ( Fig. 5).

Ecology and distribution: —Sandy substrates in river basins. It is probably the highest-altitude representative of Corispermum (alt. 4000−4700 m). The species was collected from a single locality ( Fig. 3 ) with many specimens being deposited in PE.

IUCN Red List Category: —The appropriate data on abundance and/or distribution of the taxon is lacking. It can be included in the Data Deficient (DD) as well as Not Evaluated (NE) categories of IUCN Red List categories ( IUCN 2010) as there is inadequate information to make a direct or indirect assessment of its risk of extinction based on its distribution and/or population status.

Taxonomical notes: —The new species differs from all Corispermum taxa known from China and adjacent states ( Iljin 1936, Grubov 1966, Zhu et al. 2003) by the linear leaves up to 2 mm. The fruit anatomy ( Fig. 6 ) is similar to some other Tibetan species ( C. lhasaense , C. falcatum , and C. pseudofalcatum ), but the fruit and its wing are significantly smaller.

Figures

FIGURE 3. The distribution of C. iljinii (dots), C. nanum (triangles) and C. dutreuilii var. montanum (asterisk) based on the specimens seen.

FIGURE 6. Cross-section of the fruit in its middle portion of C. nanum. Abbreviations: P, pericarp (presented by the thin-walled cells); sc, seed coat; pe, perisperm. Scale bar: 20 µm.