Cheniella R.Clark & Mackinder, 2017

Clark, Ruth P., Mackinder, Barbara A. & Banks, Hannah, 2017, Cheniella gen. nov. (Leguminosae: Cercidoideae) from southern China, Indochina and Malesia, European Journal of Taxonomy 360, pp. 1-37 : 9-11

Cheniella R.Clark & Mackinder gen. nov.

urn:lsid:ipni.org:names:77165904-1

Fig. 4

Phanera subg. Phanera subsect. Corymbosae de Wit, Reinwardtia 3 (4): 387 (de Wit 1956). – Bauhinia sect. Phanera ser. Corymbosae (de Wit) Wunderlin, K. Larsen & S.S. Larsen, Biologiske skrifter 28: 19 ( Wunderlin et al. 1987).

Bauhinia ser. Corymbosae Zhang & T.C.Chen, Acta Botanica Austro Sinica 8: 31 ( Zhang & Chen 1992).

Diagnosis

Similar to Phanera , but with an elongate hypanthium, equal in length or much longer than the sepals (vs hypanthium shorter or absent), fruit indehiscent (vs usually dehiscent), fruit many-seeded (10–)15– 30(– 36) seeds (not (1–)3–7(–12) seeds), funicle extending most of the circumference of the seed (vs funicle much shorter).

Etymology

Named for Prof. Chen Dezhao (Chen Te-chao), who described three of the (then) five species of Cheniella gen. nov. known from China. The fossil species Bauhinia cheniae Qi Wang, Z.Q.Song, Y.F.Chen, S.Shen & Z.Y.Li ( Wang et al. 2014) from the late Eocene-Oligocene Ningming Formation in Ningming County (Guangxi Zhuang Autonomous Region, South China) was likewise named for Prof. Chen Dezhao.

Type

Bauhinia corymbosa Roxb., Flora Indica 2: 329 ( Roxburgh 1832).

Genus description

Lianas or scandent shrubs with tendrils. Leaves entire, emarginate, or bilobed; secondary veins 4–10, tertiary venation highly reticulate. Inflorescence corymbose or racemose. Bracts at base of axis, linear. Bracteoles in pairs midway along the pedicel, filiform. Hypanthium elongate, at least as long as but usually much longer than the sepals, longitudinally ridged. Calyx 5-lobed, splitting irregularly into 2–5 lobes at anthesis. Petals 5, subequal to unequal, short-clawed, hairy on the outer surface; usually white, otherwise pink, or yellowish green. Fertile stamens 3, filaments glabrous. Staminodes 7, glabrous, 2 inserted individually between the stamens, the remaining 5 mounted on a raised, fleshy disc that is open at the lower end, with sterile antherodes, these caducous. Ovary glabrous, or with some hairs on basal part. Stigma capitate, peltate. Fruit compressed, not woody, narrowly to broadly oblong, glabrous, many seeded, indehiscent or tardily dehiscent. Seeds (10–)15–36 per fruit; with rim-like funicle extending along the majority of the seed circumference (known in 5 species).

Key to the species of Cheniella gen. nov. (see comparison of key characters in Table 1 )

1. Leaf entire to emarginate.………………………………………………..………………… 2

– Leaf bilobed to at least 1/10 of length ………………………………………………………….. 4

2. Leaf on lower surface moderately to densely dark ferruginous tomentose, sparsely white tomentose on upper surface (or with few hairs at the base); petioles 0.5–1.4 cm; inflorescence a raceme, densely ferruginous tomentose, the axis 5–13 cm; pedicels 1.3–1.6 cm; hypanthium (2–) 23–25 mm ..............… ……………………………………….. 3. C. clemensiorum (Merr.) R.Clark & Mackinder comb. nov.

– Leaf on lower surface sparsely to moderately pale ferruginous appressed hairy, tomentose, villose, or pilose on veins, upper surface glabrous (or with sparse hairs on the midvein only); petioles 0.8–2.8 mm; inflorescence a raceme or corymb, the axis usually shorter than 10 cm, sparsely to moderately pale tomentose; pedicels 1.5–3.3 mm; hypanthium 7–20 mm ......……………….……………………………………………… 3

3. Leaf lower surface sparsely to moderately pilose, pubescent or villose; petals 7–12 × 4–10 mm, claw 1–4 mm; ovary with few hairs at the base (occasionally glabrous) ........................................... .....….................................……. 1. C. quinnanensis (T.C.Chen) R.Clark & Mackinder comb. nov.

– Leaf underside pilose only on veins or at base; petals 11–22 × 6–15 mm, claw 4–8 mm; ovary glabrous …..………………………….. 2. C. ovatifolia (T.C.Chen) R.Clark & Mackinder comb. nov.

4. Leaf bilobed almost to the base, or the lobes joined by ca 1–2 mm ….................................... ..............................................… 7. C. didyma (H.Y.Chen) R.Clark & Mackinder comb. nov.

– Leaf bilobed to a lesser degree (to 7/8 or less), the lobes joined by at least 3 mm ……… 5

5. Hypanthium 4–6[–10] mm, distinctly inflated at the base; petals yellowish or greenish; stipe hairy, ovary with hairs on lower ca half or almost whole length, particularly along lower suture …………………………………. 4. C. touranensis (Gagnep.) R.Clark & Mackinder comb. nov.

– Hypanthium 6–30 mm, not inflated at the base; petals usually white (to occasionally pale yellow) or pink; ovary glabrous or with few hairs at base ………………………………….. 6

6. Petals ca 5–8 × 1.5–3 mm, densely sericeous on outer surface; leaf subglabrous on underside …………………….… 8. C. damiaoshanensis (T.C.Chen) R.Clark & Mackinder comb. nov.

– Petals 8–19 × 4–14 mm, sparsely to moderately sericeous on outer surface; leaf sparsely to moderately tomentose on underside ……………………………………………………….. 7

7. Hypanthium glabrous, or with very few hairs at base ….......................................................... .............……………..…....… 10. C. glauca (Wall. ex Benth.) R.Clark & Mackinder comb. nov.

– Hypanthium sparsely to moderately (occasionally densely) hairy …………………….…… 8

8. Leaf bilobed 1/10 (or less)–½ from apex (occasionally slightly more), 4.2–9 × 4.7– 10.7 cm; petals 10–19 × 5–14 mm; stamens 12–17 mm; fruit 16.5–27 × 3.3–5.6 cm.………..……. 9. C. tenuiflora (Watt ex C.B.Clarke) R.Clark & Mackinder comb. nov.

– Leaf bilobed for ½–⅞ from apex, 2–5 × 2–6.3 cm; petals 8–14 × 4–9 mm; stamens 8–10 mm; fruit 10–25 × 1.5–2.5 cm .....……….……………………………………..………….. 9

9. Leaf bilobed ⅓–⅔ from apex; secondary leaf veins (8–)10; flower white; pedicel 0.7–1.7 cm; fruit indehiscent (or tardily dehiscent) ............................................................................................. ..…………………………….….. 6. C. lakhonensis (Gagnep.) R.Clark & Mackinder comb. nov.

– Leaf bilobed ⅔–⅞ from apex; secondary leaf veins 4–6; flower pink; pedicel 1.0– 2.6 cm; fruit dehiscent along the ventral (lower) suture when mature ................................................. ..............................…...……...... 5. C. corymbosa (Roxb.) R.Clark & Mackinder comb. nov.

Figures

Fig. 4. Illustration of Cheniella R.Clark & Mackinder gen. nov. A. Cheniella ovatifolia (T.C.Chen) R.Clark & Mackinder comb. nov., habit (Harder et al. 4249). B. C. glauca (Wall. ex Benth.) R.Clark & Mackinder comb. nov., leaf abaxial surface (Horsfield 165). C. C. quinnanensis subsp. villosa R.Clark & Mackinder subsp. nov., leaf abaxial indumentum (Tu 924). D. C. quinnanensis (T.C.Chen) R.Clark & Mackinder comb. nov. subsp. quinnanensis, leaf abaxial indumentum (Forrest 11844). E. C. tenuiflora (Watt ex C.B.Clarke) R.Clark & Mackinder comb. nov., flower (Urquhart s.n.). F. C. touranensis (Gagnep.) R.Clark & Mackinder comb. nov., flower (Henry 10175). G. C. touranensis, ovary (Harder & al. 2387). H. C. quinnanensis, ovary (Bar 2676). I. C. tenuiflora, fruit (Winit 1455). J. C. corymbosa (Roxb.) R.Clark & Mackinder comb. nov., fruit (Cult. Calcutta B.G. s.n.). K. C. corymbosa, seed, three views (Cult. Calcutta B.G. s.n.). L. C. tenuiflora, schematised flower, showing staminodes (2 broken), bases of 3 stamen filaments (solid black), base of ovary (dotted), bases of petals (dotted outlines), sepals and hairs omitted. Drawn by Andrew Brown.