Hyalolaena zhang-minglii Lyskov & Kljuykov, 2019

Lyskov, Dmitry, Kljuykov, Eugene, Ukrainskaja, Uliana & Tojibaev, Komiljon, 2019, Notes on the genus Hyalolaena (Apiaceae) with description of a new species H. zhang-minglii from Xinjiang, western China, Phytotaxa 388 (3), pp. 229-238 : 232-233

Hyalolaena zhang-minglii Lyskov & Kljuykov , sp. nov. ( Fig. 1–3 )

The new species is similar to H. issykkulensis and differs by filiform terminal segments of radical leaves (vs. linear), all fruit ribs subequal narrow-winged (vs. dorsal ribs filiform and marginal narrow-winged), shorter root, and greater number of secretory ducts on commissural side (9–10 vs. 3–4).

Type:— CHINA. Xinjiang, Ili Kazakh Autonomous Prefecture , Tekes County, Eastern Tian Shan , northern foothills of Narat Range , ascent from Keshi Kushitai to east, meadow steppe used for haying on gentle slope. alt. 1850 m, 42º57 ′ 50 ′′ N, 82º00 ′ 21 ′′ E, 12 August 2017, Seregin & Lyskov A-2556 (holotype: MW0595674 ; isotype: PE, W) .

Monocarpic, perennial, herbaceous plants with cylindrical or fusiform, brown or brownish black thickened taproot 7–12 mm. Stems 60–80 cm tall and up to 2–3 mm ٜ at base, single, plump, round, slightly ribbed at base and under umbel, glabrous, with branches directed from middle of stem, covered with fibrous collar remains of petioles, sheaths, and older leaves; branches forming corymbose structure ( Fig. 1 ). Basal leaves forming rosette; petioles short, with lanceolate-triangular sheaths at base, glabrous; leaf blades up to 5 cm long and 1.5 cm wide, obovate-lanceolate or lanceolate, 3-pinnate with sessile segments, glabrous; ultimate leaf segments filiform up to 4 mm long. Stem leaves with narrow sheaths and short petiole, 3-pinnate, significantly smaller than basal leaves; ultimate leaf segments filiform up to 3 mm long; medial leaves more simplified, ultimate leaf segments up to 2 mm long; the highest stem leaves only with sheaths; number of stem leaves 6–7. Umbels 6–7 cm in diameter, number of rays 5–11; rays unequal, thin, 2.5–3 cm long. Number of bracts 6–8, narrow-lanceolate, brown, with albescent margin, glabrous. Umbellets with 10–12 flowers; pedicels thin, round, unequal, 3–4 mm long. Number of bracteoles 4–5, narrow-lanceolate, with albescent margin. Calyx teeth obscure, petals white, stylopods conical or low conical, styles 0.5–0.7 mm reflected. Mericarps elliptic ( Fig. 2 ), up to 3.5 mm long, 1.5–1.7 mm wide; carpophore bifurcate to base; mericarps homomorphic, slightly dorsally compressed, glabrous; only primary ribs present; all ribs subequal, narrow-winged, straight, with entire margin; commissure intermediate; secretory ducts between ribs one broad and one or two smaller; two broad and 9–10 smaller at commissural side; endosperm flat at commissural side.

Additional specimens studied (paratypes): — CHINA. Xinjiang, Ili Kazakh Autonomous Prefecture, Tekes County, Eastern Tian-Shan, northern foothills of Narat Range, left bank of the Kuokesu River above Kezile Kuolacun, rocks above Z 793 county road. alt. 1400 m, 42º55 ′ 34 ′′ N, 81º55 ′ 12 ′′ E, 11 August 2017, Seregin & Lyskov A-2532 ( MW 0595673, W).

Etymology: —The species is named in honor of the late botanist Zhang Ming-Li, who arranged our expedition to western China and contributed considerably to the study of the flora of Xinjiang.

Distribution: —The species is known only from the Narat Range ( Fig. 3 ). The closest related species H. issykkulensis is distributed in more western terretories: northeast Kyrgyzstan and border areas of Xinjiang ( Pimenov 2017, Pimenov & Klyuykov 2002).

Phenology: —Flowering probably in June, and fruiting in the second half of July to August.

Note: —The holotype of H. zhang-minglii was collected on meadow steppe used for haying, therefore the species can be considered as threatened species. Four species of Hyalolaena are listed for China after description of a new species. All species are distributed in Xinjiang ( Pimenov & Kljuykov 1990, Pu & Watson 2005, Pimenov 2017).

Figures

FIGURE 1. Hyalolaena zhang-minglii (holotype, MW0595674).

FIGURE 2 Mericarp of Hyalolaena zhang-minglii: cross section (A) and general view (B). 1—exocarp; 2—mesocarp; 3—endosperm; 4—secretory duct; 5—vascular bundle; 6—cells with lignified walls; 7—cavity.

FIGURE 3 Distribution of Hyalolaena zhang-minglii (stars) and distribution of Hyalolaena species in Uzbekistan: H. bupleuroides (triangle), H. jaxartica (dots), and H. intermedia (squares).