Corydalis hualongshanensis D.Wang, 2017

Wang, Dong, Xu, Xiaodong & Liu, Ping, 2017, Corydalis hualongshanensis, a new species of Corydalis sect. Fumarioides (Papaveraceae) from Shaanxi, China, Phytotaxa 307 (2), pp. 153-158 : 153-157

Corydalis hualongshanensis D.Wang , sp. nov. ( Figs. 1 , 2 & 3A )

Type: — CHINA. Shaanxi Province (Ớffl): Ankang City (Ǡẘḿ), Hualongshan National Nature Reserve (ṁAEƜOiẎDZHṂDzṖỮ), Baizigou (ffiừNj), growing in mixed forest margins and forest understory, 32°00 ′ 24.3 ″ N, 109°20 ′ 40.7 ″ E, elev. 2250–2310 m, 5 September 2016, D.Wang 160437 (holotype CCNU!, isotype PE!)

Diagnosis: —This species is closely related to C. fargesii in having entire floral bracts, obtuse crest overtopping apex on outer petals, slightly curved spur that is approximately two times as long as petal lobes, with nectary extended through 2/3–4/5 spur, rectangular stigma with 4 distinct apical papillae, and obovoid to cylindric capsule, but differs by its papillose-hairs finely distributed on the peduncle, the pedicel, the apical part of outer petal, and the surface of fruit.

Description: —Biennial suberect to diffuse herbs, 0.5–1.2 m tall. Taproot slender to swollen with numerous small fibrous roots. Stem ridged or narrowly winged, hollow and weak, leafy and much branched distally. Basal leaves early withering, petiole vaginate; middle and upper leaves with petiole 1–7(–12) cm long, blade broadly ovate, 9–15 × 7–13 cm, 2(–3)- pinnate, primary leaflets distant, petiolulate; ultimate leaflets entire to 2–3-lobed, ovate to obovate, abaxial veins densely with thin papillae, apex obtuse. Racemes several, peduncle slender, papillose-hairy, 8–10 cm long, with 10–23 flowers; bracts ovate to narrowly ovate, small, 1.5–2.5 × 0.6–1 mm, entire, margin with papillose-hairs; pedicel 1–2 mm long, finely papillose-hairy, recurved in fruit. Flower 20–23 mm long (measured along curve), sepals ca. 0.5 mm in diameter, rounded, dentate; corolla yellow; outer petals subacute, with obtuse usually dentate crest clearly overtopping apex, upper petal subacute, the apical part with finely papillose-hairs (except crest), spur slightly sigmoidally curved, cylindric, 15–17 mm long, nectary ca. 2/3–4/5 as long as spur, thin, lower petal shallowly saccate, base shortly clawed, apex reflexed at anthesis; inner petals not dark tipped, 6–7 mm long; ovary finely papillose-hairy, with 2–5 ovules, stigma rectangular, with 4 distinct apical papillae and 2–4 subterminal papillae (sometimes 2 of them confluent), a pair of submarginal lateral geminate papillae, and one small papilla at basal corners. Capsule explosively dehiscent, narrowly obovoid-cylindric, 4–8 × 2–2.5 mm, finely papillose-hairy, 2–5-seeded; style ca. 3 mm. Seeds in one row, ca. 1.5 mm in diameter, smooth, elaiosome small, white.

Phenology: —Flowering from July to September and fruiting from August to October.

Habitat and Distribution: — Corydalis hualongshanensis occurs usually in mixed forest margins and forest understory with elevations ranging from ca. 1440 m to 2310 m. It is known only from a very restricted area in the Hualongshan National Nature Reserve, and two adjacent locations in Zhenping county, where are several kilometers southeast of the type locality. The forest is commonly dominated by Cornus walteri Wangerin ( Cornaceae ), Betula albosinensis Burkill ( Betulaceae ), Elaeagnus wushanensis C.Y.Chang ( Elaeagnaceae ), Malus kansuensis (Batalin) C.K.Schneid. ( Rosaceae ), and Rubus mesogaeus Focke ex Diels ( Rosaceae ).

Etymology: —The specific epithet refers to the geographic name of the type locality.

Chinese name suggested: —Hua long shan huang jin (ṁAEƜẤAE).

IUCN Red List category: —Although a few localities of C. hualongshanensis have been found, it is probably more common than this number suggests. In the field, we discovered three populations of the species several kilometers apart from each other, each consisting of thousands of individuals. According to the criteria of IUCN Red List ( IUCN 2012), the new species should be classified as DD (Data Deficient).

Additional specimens examined (paratypes):— CHINA. Shaanxi: Zhenping, Miaobachun ( Û ṄỦ), Wuchigou ( Ƃ ṀNj), 31°57 ′ 48.31 ″ N, 109°23 ′ 6.79 ″ E, elev. 1518 m, 1 September 2015, Liuping. 019 ( CCNU) ; Miaoba chun ( Û ṄỦ), Shimengou (ƁLJNj), 31°56 ′ 46.63 ″ N, 109°23 ′ 24.85 ″ E, elev. 1447 m, 6 September 2016, D.Wang & X.D.Xu 160441 ( CCNU) .

Discussion: — Corydalis hualongshanensis is most similar to C. fargesii , but differs in having papillose-hairs on the peduncle, the pedicel, the apical parts of outer petals and the fruit. It is also similar to C. pseudofargesii and C. shennongensis , but differs from the former by its bracts that is not divided and nectary that is about 2/3–4/5 length of spur, and from the latter by its spur that is two times as long as petal lobe, sepal that is rounded and about 0.5 mm in diameter, and bract that is ovate and about 1.5–2.5 × 0.6–1 mm ( Figs. 2 & 3 ). In respect to stigma morphology of C. hualongshanensis , we found that the number of marginal papillae showed a little variation among individuals, while the outline of stigma and the number of apical papillae are stable. Corydalis hualongshanensis and the related species are compared with each other in table 1. The four species can also be distinguished by the following key.

Key to species of Corydalis hualongshanensis and morphologically related species

1. Spur equaling petal lobe ........................................................................................................................................... C. shennongensis

- Spur ca. 2× as long as petal lobe ....................................................................................................................................................... 2

2. Nectary extended through ca. 1/3 of spur ................................................................................................................ C. pesudofargesii

- Nectary extended through 2/3–4 /5 of spur.......................................................................................................................................3

3. Pedicel, the apical part of outer petal and capsule glabrous ............................................................................................... C. fargesii

- Pedicel, the apical part of outer petal and capsule finely papillose-hairy ......................................................... C. hualongshanensis

Figures

FIGURE 1. Corydalis hualongshanensis. A. Plant showing habit; B. Bract; C. Flower; D. lower petal (left: adaxial view, right: abaxial view); E. inner petals (left: adaxial view, right: abaxial view); F. stamen; G. pistil; H. stigmas; I. seed. Drawn by D. Wang from D. Wang 160437 (CCNU).

FIGURE 2. A–G: Habit and morphology of Corydalis hualongshanensis. A. habit; B. inflorescence; C. fruit; D. sepal; E. the apical part of outer petal; F. Fruit; G. 1–8: 1. bract; 2. spur and nectary; 3. lower petal (left: adaxial view, right: abaxial view); 4. inner petal (left: adaxial view, right: abaxial view); 5. stamens (left: abaxial view, right: adaxial view); 6. pistil; 7. stigmas; 8. seed. Photo credits: D. Wang.

FIGURE 3.A. Corydalis hualongshanensis. B(1–3). Corydalis pseudofargesii. 1. flower; 2. stigma; 3. fruit. C(1–3). Corydalis fargesii. 1. flower; 2. stigma; 3. fruit. D(1–3). Corydalis shennongensis. 1. flower; 2. stigma; 3. fruit. Photo credits: D. Wang.