Sunday, March 27, 2022

[Botany • 2022] Duhaldea lachnocephala (Asteraceae: Inuleae: Inulinae) • A New Species from Yunnan, southwest China


Duhaldea lachnocephala Huan C. Wang & Feng Yang,
 
in Yang, Ye, Huang, Wang & Wang. 2022. 

Abstract
Duhaldea lachnocephala Huan C. Wang & Feng Yang (Asteraceae: Inuleae) is described and illustrated as a new species. The new species is only known from the Luzhijiang valley, Yunnan Province, southwest China. It is characterized prominently by having dense arachnoid-lanate hairs on stems, leaves and phyllaries, and white marginal florets usually 2–3-seriate. Morphological comparisons with its closest relatives D. nervosa, D. revoluta and D. simonsii are presented. A preliminary conservation assessment of D. lachnocephala is also made under the IUCN criteria.

Keyword: Compositae, Duhaldea nervosa, D. simonsii, endemism, Luzhijiang valley, marginal floret

Duhaldea lachnocephala sp. nov. 
 A. Habit. B. Abaxial surface of leaf. C. Marginal floret (lateral view). D. Phyllaries from outer (left) to inner (right). E. Disc floret (lateral view). F. Marginal floret (apical view). G. Style of disc floret. H. Plumose bristle. I. Style arms with acute sweeping hairs. J. Stamens showing tailed anthers. K. Disc floret corolla dissected (stamens removed) to showing attachment points of the filaments.



Duhaldea lachnocephala sp. nov. (A–G) and D. nervosa (H–N).
A, H. Habit. B, I. Adaxial surface of leaf. C, J. Abaxial surface of leaf. D, K. Capitula (apical view). E, L. Capitula (dorsal view). F, M. Disk floret and pappus. G, N. Cypsela of disk floret.

Duhaldea lachnocephala Huan C.Wang & Feng Yang, sp. nov. 
毛苞羊耳菊 

Diagnosis: Duhaldea lachnocephala is most similar to D. nervosa (Wall. ex DC.) Anderb., but clearly differs from the latter by its whole plant with dense arachnoidlanate (vs. usually pilose or strigose) hairs except for the adaxial surface of leaf, capitula larger, 3–4 cm (vs. 1.5– 2.5 cm) in diameter, involucres hemispheric (vs. campanulate to broadly campanulate), phyllaries subequal (vs. outer series smaller), loose (vs. compressed) in arrays, 10–15 × 1–3 mm (vs. 7–10 × 0.7–1.2 mm), marginal florets 2- or 3-seriate (vs. usually uniseriate), corollas 10–12 × 1–3 mm (vs. 8–13.5 × 1.5–2.5 mm). 

Distribution and habitat: Duhaldea lachnocephala appears to be a rare species endemic to Yunnan, southwest China. It was only collected from two localities in valley of the Luzhijiang River, an upper tributary of the Hong (Red) River which flows from Yunnan in southwest China through northern Vietnam to the Gulf of Tonkin. The climate in Luzhijiang valley is semi-dry and hot, with an average temperature of 21.00℃ and a total annual precipitation of 822.80 mm. D. lachnocephala occurs in the xerophilous scrubs or grasslands at elevations of 1200–1500 m, and its association includes Phyllanthus emblica Linn. (Phyllanthaceae), Paliurus orientalis (Franch.) Hemsl. (Rhamnaceae), Dalbergia yunnanensis Franch. (Fabaceae), Symphoricarpos sinensis Rehd. (Caprifoliaceae), Pterygiella luzhijiangensis Huan C. Wang (Orobanchaceae) (an endemic species of Luzhijiang valley recently discovered by Qiao et al. (2018)), Silene otodonta Franch. (Caryophyllaceae), Spodiopogon sagittifolius Rendle (Poaceae), Heteropogon contortus (Linn.) Beauv. ex Roem. et Schult. (Poaceae) and Themeda caudata (Nees ex Hooker et Arnott) A. Camus (Poaceae). 

 Etymology: The specific epithet lachnocephala is derived from the Greek words “lachnos” (soft and thick hairs) and “kephale” (head), referring to the capitula of this new species with dense arachnoid-lanate hairs.

   


Feng Yang, Jing-Yi Ye, Qiang-Chun Huang, Qiu-Ping Wang and Huan-Chong Wang. 2022. Duhaldea lachnocephala (Asteraceae: Inuleae: Inulinae), A New Species from Yunnan, southwest China. Taiwania. 67(2); 217-222. DOI: 10.6165/tai.2022.67.217



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