Ancylostemon in Flora of China @ efloras.org

9. Ancylostemon Craib, Notes Roy. Bot. Gard. Edinburgh. 11: 233. 1919.

直瓣苣苔属 zhi ban ju tai shu

Herbs, perennial, epipetric or rarely terrestrial, rhizomatous, stemless. Leaves many, basal; leaf blade puberulent to villous, rarely glabrescent, base cuneate to subcordate. Inflorescences lax, axillary, 1-10-flowered cymes; bracts 2, opposite. Calyx actinomorphic, 5-sect from base to 5-lobed from above middle; segments equal to subequal. Corolla orange to yellow or white, rarely pink, zygomorphic, inside glabrous to puberulent, rarely pilose near base; tube narrowly funnelform to cylindric, slightly gibbous abaxially, longer than limb, 3-8 mm in diam.; limb 2-lipped to slightly 2-lipped; adaxial lip 2-lobed, emarginate, or rarely undivided, shorter than abaxial lip; abaxial lip 3-sect from base, lobes equal or central longer than laterals, apex rounded or rarely acute. Stamens 4, adnate to corolla tube above or rarely below middle, included or rarely exserted; anthers basifixed, coherent in pairs, thecae divergent, not confluent, dehiscing longitudinally; connective not projecting; staminode 1, adnate to adaxial side of corolla tube. Disc ringlike or rarely cupular. Ovary narrowly oblong, 1-loculed; placentas 2, parietal, projecting inward, 2-cleft. Stigmas 2, equal, 2-lipped, undivided. Capsule straight in relation to pedicel, oblong lanceolate to oblanceolate, much longer than calyx, dehiscing loculicidally to base; valves 2, straight, not twisted. Seeds unappendaged.

* Twelve species: endemic to China.

Ancylostemon flabellatus C. Y. Wu ex H. W. Li (Bull. Bot. Res., Harbin 3(2): 16. 8. 1983) is not included in the treatment because it is known only from fruiting specimens and cannot be definitively placed in Pan's classification (Fl. Reipubl. Popularis Sin. 69: 190-203. 1990). Its placement in Ancylostemon is uncertain since other genera (e.g., Tremacron, Isometrum, and Oreocharis) are virtually indistinguishable using vegetative or fruit characters.

1 Calyx 5-sect from base or near base, tube to 1 mm. (2)

+ Calyx 5-lobed from below to above middle, tube at least 2 mm. (6)

2 (1) Leaf blade adaxially with only 1 kind of hairs, white puberulent or sparsely brown villous, often glabrescent; corolla 1.1-2 cm. (3)

+ Leaf blade adaxially with at least 2 kinds of hairs, both villous and puberulent to pubescent or villous; corolla 1.5-3 cm. (4)

3 (2) Leaf blade 1.1-4.4 X 0.7-1.8 cm; lateral veins 3-5 on each side of midrib; peduncle 3-8 cm; bracts 2-4 mm, glabrous to sparsely villous 1 Ancylostemon humilis

+ Leaf blade 3-12 X 1-3.2 cm; lateral veins 7 or 8 on each side of midrib; peduncle 12-27 cm; bracts 6-18 mm, brownish pannose 2 Ancylostemon notochlaenus

4 (2) Corolla pink; leaf blade margin serrate, base usually oblique, cuneate; peduncle sparsely puberulent; bracts apparently absent 4 Ancylostemon ronganensis

+ Corolla orange to yellow; leaf blade margin coarsely dentate-serrate or crenate to lobulate, base cuneate to cordate; peduncle brown villous, sometimes also puberulent; bracts 2-8 mm. (5)

5 (4) Corolla adaxial lip 2-lobed; bracts linear to oblong, 2-5 X 0.7-1.2 mm; calyx segment margin entire; disc ca. 2.5 mm, subentire 3 Ancylostemon mairei

+ Corolla adaxial lip emarginate; bracts narrowly oblong to lanceolate or oblanceolate, 3-8 X 1.5-3 mm; calyx segment margin dentate, rarely subentire; disc 1-1.5 mm, 5-lobed 9 Ancylostemon saxatilis

6 (1) Petiole to 1 cm; leaf blade rhombic to rhombic-ovate; lateral veins 2 or 3 on each side of midrib, inconspicuous, margin shallowly crenate to denticulate 10 Ancylostemon rhombifolius

+ Petiole to 2-12(-14) cm; leaf blade ovate to broadly ovate, elliptic, lanceolate, or oblong, rarely ovate- rhombic; lateral veins 3-7 on each side of midrib, conspicuous, margin coarsely to double serrate, crenate, or dentate to lobulate, rarely merely crenate to dentate or serrate. (7)

7 (6) Leaf blade adaxially densely puberulent; peduncle spreading pubescent 8 Ancylostemon bullatus

+ Leaf blade adaxially both puberulent and villous, at least sparsely so along veins; peduncle villous, sometimes also pubescent. (8)

8 (7) Corolla limb slightly 2-lipped, all lobes subequal; petiole, peduncle, and calyx segments bristly-villous, sometimes also puberulent. (9)

+ Corolla limb 2-lipped, abaxial lip at least 2 X longer than adaxial lip; petiole, peduncle, and calyx segments villous, sometimes also pubescent or puberulent. (10)

9 (8) Leaf blade ovate, ca. 3.5 X 2 cm; petiole ca. 2 cm; calyx 10-11 mm 11 Ancylostemon vulpinus

+ Leaf blade broadly ovate, 4-5.5 X 3-4.8 cm; petiole to 7.5 cm; calyx 5-8 mm 12 Ancylostemon trichanthus

10 (8) Corolla adaxial lip 2-lobed; petiole to 4 cm; leaf blade 2.2-4 X 2-3 cm, margin crenate to dentate or serrate, not lobulate; peduncle 4-7 cm, brown villous 7 Ancylostemon gamosepalus

+ Corolla adaxial lip undivided to emarginate; petiole to 12(-14) cm; leaf blade 2.5-16 X 1.5-9 cm, margin coarsely dentate to serrate or crenate, to lobulate or nearly so; peduncle 2.4-15(-22) cm, brown villous and pubescent or puberulent. (11)

11 (10) Leaf blade margin coarsely dentate-serrate or crenate to nearly lobulate; corolla adaxial lip 1-3 mm wide, abaxial lip ca. 1 cm, lobes ovate-orbicular or broadly ovate 9 Ancylostemon saxatilis

+ Leaf blade margin coarsely double dentate to double serrate or lobulate, lobes dentate to serrate; corolla adaxial lip 4-7 mm wide, abaxial lip 7-8 mm, lobes oblong to obovate. (12)

12 (11) Stamens 6-15 mm, filaments sparsely puberulent; disc ca. 1 mm, entire; calyx lobes 2-5 X 1-2 mm; bracts linear to narrowly triangular, 4-7 X 0.7-1.5 mm 5 Ancylostemon convexus

+ Stamens 5-6 mm, filaments glabrous; disc 2-5 mm, 5-lobed; calyx lobes 1-2.5 X 1.5-3 mm; bracts narrowly oblong to obovate, 4-7 X 1-2 mm 6 Ancylostemon aureus

List of lower taxa