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74. Psychotria Linnaeus, Syst. Nat., ed. 10. 2: 906, 929, 1364. 1759.
九节属 jiu jie shu
Authors: Tao Chen & Charlotte M. Taylor
Cephaelis Swartz.
Shrubs, small trees, or rarely vines twining and/or climbing by adventitious roots (Psychotria serpens), [infrequently dioecious or polygamo-dioecious], unarmed, tissues and/or pubescence often drying dark gray or dark reddish brown. Raphides present. Leaves opposite or rarely in whorls of 3 or 4, often with foveolate and/or pubescent domatia; stipules caducous or infrequently persistent, interpetiolar or sometimes shortly united around stem, entire or 2-lobed, rarely with lobe glandular, inside (i.e., adaxially) at base with well-developed colleters, these usually persistent after stipule falls, usually drying red-brown. Inflorescences terminal often becoming displaced to pseudoaxillary or rarely axillary, cymose, corymbose, paniculiform, glomerulate, or capitate, several to many flowered, sessile to pedunculate, bracteate with bracts sometimes reduced or sometimes enlarged or involucrate. Flowers sessile to pedicellate, bisexual, usually distylous [or infrequently unisexual]. Calyx limb (4 or)5(or 6)-lobed. Corolla white, yellow, or flushed with pink, funnelform to tubular, inside glabrous or variously pubescent, lobes (4 or)5(or 6), valvate in bud, sometimes abaxially with thickenings or horns near apex. Stamens (4 or)5(or 6), inserted in corolla tube or throat, usually included or partially exserted in long-styled flowers and exserted in short-styled flowers; filaments short to developed; anthers dorsifixed near base. Ovary 2-celled, ovules 1 in each cell, basal; stigmas 2, linear to subcapitate, usually exserted in long-styled flowers and included in short-styled flowers. Fruit red, orange, or infrequently white (P. serpens), purple (P. manillensis), or black (P. cephalophora, P. straminea), drupaceous, fleshy, ellipsoid, ovoid, or subglobose, with calyx limb persistent or infrequently deciduous, with pedicels or stipitate base sometimes elongating; pyrenes 2, 1-celled, each with 1 seed, plano-convex, bony, on dorsal (i.e., abaxial) surface smooth or longitudinally ridged, on ventral surface smooth or longitudinally sulcate; seeds medium-sized, ellipsoid to plano-convex, with testa thin; endosperm fleshy or corneous, sometimes ruminate; embryo small, basal; cotyledon flat.
About 800-1500 species: tropical and subtropical Africa, America, Asia, Madagascar, and Pacific islands; 18 species (five endemic) in China.
The genus Cephaelis was separated from Psychotria by numerous authors in the 19th and first part of the 20th centuries, based on inflorescence form: Cephaelis included species with capitate inflorescences with enlarged, often involucral bracts, vs. branched inflorescences with smaller bracts in Psychotria. However, it is now clear that this inflorescence arrangement has arisen far more than once within this group and that "Cephaelis" actually included a polyphyletic set of species that are more closely related to various other species of Psychotria than to each other. Consequently, recent authors (e.g., Steyermark, Mem. New York Bot. Gard. 23: 443-717. 1972; Taylor, Opera Bot. Belg. 7: 261-270. 1996) have formally synonymized Cephaelis with Psychotria. A recent treatment of Psychotria in the Philippines (Sohmer & Davis, Sida, Bot. Misc. 27: 1-247. 2007) does not consider any species or names outside its study area but includes some Chinese species that occur in that region. However, these authors have a partially different species concept and morphological interpretation of inflorescence characters from C. M. Taylor, so their work is not completely comparable to the treatment here.
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| 1 |
Climbing or creeping vines or lianas with adventitious roots, often on tree trunks or rocks; fruit white. |
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14 P. serpens |
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Erect, self-supporting subshrubs, shrubs, and small trees growing on ground; fruit orange or red |
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(2) |
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| 2 (1) |
Leaves strigose to hirsute in similar density on both sides; stipules 15-25 mm, deeply bilobed. |
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12 P. pilifera |
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Leaves glabrous adaxially, or pubescent adaxially with distinctly different pubescence than on abaxial surface; stipules 1.5-20 mm, entire to bilobed |
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(3) |
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| 3 (2) |
Inflorescences capitate, pedunculate, and enclosed by a cupuliform involucre formed of fused bracts. |
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9 P. laui |
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Inflorescences capitate to branched, sessile to pedunculate, and variously bracteate, bracts when present free and not forming a single involucre |
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(4) |
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| 4 (3) |
Calyx limb 1.3-3 mm, shallowly to deeply lobed |
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(5) |
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Calyx limb 0.5-1.2 mm, truncate to deeply lobed |
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(9) |
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| 5 (4) |
Inflorescences thyrsiform to paniculate, branched to 2 or 3 orders and with well-developed secondary axes. |
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18 P. yunnanensis |
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Inflorescences capitate, subcapitate, or congested-cymose, unbranched or branched to 1 or 2 orders but without well-developed secondary axes |
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(6) |
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| 6 (5) |
Inflorescences capitate to densely congested-cymose, subglobose in outline, sessile or with peduncle to 1 cm. |
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13 P. prainii |
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Inflorescences capitate, subcapitate, or shortly congested-cymose, ellipsoid to ovoid or pyramidal in outline, sessile to pedunculate with peduncles to 6 cm |
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(7) |
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| 7 (6) |
Subshrubs, often rhizomatous; leaves with well-developed, generally straight submarginal vein extending along most or all of length of blade. |
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2 P. calocarpa |
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Shrubs or small trees; leaves without submarginal vein or with submarginal vein incomplete or only weakly developed, extending for up to 1/2-2/3 of length of blade |
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(8) |
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| 8 (7) |
Inflorescences sessile or with peduncle up to 0.6 cm; stipules 3-12 mm; Hainan. |
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7 P. hainanensis |
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Inflorescences pedunculate, peduncle 0.5-6 cm; stipules 8-20 mm; Yunnan. |
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11 P. morindoides |
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| 9 (4) |
Inflorescences capitate to subcapitate or congested-cymose, unbranched or branched but without well-developed secondary axes, or with secondary axes but then primary axis not developed |
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(10) |
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Inflorescences thyrsiform, paniculate, corymbiform, or congested-cymose to laxly cymose, branched, with both primary and secondary axes developed |
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(11) |
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| 10 (9) |
Flowers subsessile to pedicellate in a single head, with all flowers arising from one axis. |
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3 P. cephalophora |
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Flowers variously sessile to pedicellate in a subcapitate head or congested cyme, flowers arising from more than one point or axis. |
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8 P. henryi |
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| 11 (9) |
Stipules 10-15 mm with at least some of them more than 10 mm; leaves with secondary veins 12-18 pairs with 13 or more pairs on at least some leaves. |
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4 P. densa |
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Stipules 1.5-12 mm with at least some less than 10 mm; leaves with secondary veins 4-12 pairs with less than 12 pairs on at least some leaves |
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(12) |
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| 12 (11) |
Inflorescences pyramidal, with primary axis developed and longer than secondary axes. |
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16 P. symplocifolia |
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Inflorescences rounded-corymbiform to broadly pyramidal, with primary axis reduced to developed but not longer than secondary axes |
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(13) |
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| 13 (12) |
Stipules fused around stem into a distinct sheath, mostly persistent with leaves; leaves with secondary veins prominulous adaxially. |
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15 P. straminea |
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Stipules interpetiolar, caducous or deciduous, falling before some of leaves; leaves with secondary veins flat or thinly impressed adaxially |
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(14) |
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| 14 (13) |
Leaves narrowly elliptic, narrowly elliptic-oblong, narrowly lanceolate, narrowly lanceolate-oblong, or oblanceolate, 4-15 × 1-4.5 cm; stipules at least shortly 2-lobed |
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(15) |
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Leaves elliptic, broadly elliptic, broadly elliptic-oblong, ovate, lanceolate-oblong, or obovate, 5-23.5 × 2-9 cm; stipules entire to 2-lobed |
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(17) |
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| 15 (14) |
Leaves abaxially with distinctive thickened epidermis often mottled when dry, secondary veins covered by epidermis or visible but flat to only slightly thickened. |
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6 P. fluviatilis |
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Leaves abaxially with epidermis "normal," thin and not mottled when dry, secondary veins visible, with different epidermal texture from lamina, flat to prominulous |
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(16) |
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| 16 (15) |
Plants usually drying dull green, grayish brown, yellowish green, or reddish brown; inflorescences congested-cymose. |
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8 P. henryi |
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Plants usually drying reddish brown to dark brown; inflorescences laxly cymose, corymbiform. |
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17 P. tutcheri |
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| 17 (14) |
Bracts subtending flowers rather well developed, lanceolate to ligulate or triangular, 1.5-3 mm; stipules 2-lobed. |
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5 P. erratica |
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Bracts subtending flowers developed to reduced, triangular, 0.2-1.2 mm; stipules obtuse, acute, rounded, or shallowly emarginate |
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(18) |
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| 18 (17) |
Inflorescences sessile or with peduncle to 0.3 cm; leaves with secondary veins not or only weakly forming a submarginal vein. |
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1 P. asiatica |
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Inflorescences pedunculate, peduncles 0.1-3.5 cm; leaves with secondary veins free or usually forming a weak to well-developed, looping submarginal vein. |
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10 P. manillensis |
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List of lower taxa
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