RUBIACEAE  

Shrubs or small trees, usually with spines formed from modified lateral branchlets. Leaves usually clustered on short, opposite, axillary branchlets or cushion-like shoots; stipules short, ovate-acuminate or triangular, apiculate, deciduous. Flowers 1 or 2(3) together, terminating opposite pairs of abbreviated lateral shoots. Calyx 5-lobed, lobes short; tube ovoid or campanulate; limb-tube shortly cylindrical, ellipsoid or urceolate. Corolla white, densely pubescent outside except for base of tube; tube +/- campanulate, shorter than lobes, with a circular band of long hairs within. Stamens 5, arising on corolla tube or in mouth, exserted or included; filaments linear, shorter than anthers; anthers oblong or linear. Ovary 2-locular, placentae attached to septum; ovules many; style terete or thickened upwards, as long as tube or exserted; stigma ellipsoid or cylindrical, grooved or 2-lobed. Fruit 2-locular, globose, many-seeded, crowned by persistent calyx lobes. Seeds discoid or compressed-ellipsoid with slightly raised reticulation on testa.

Dwarf shrubs, rarely perennial herbs, bisexual, female, or occasionally male, bisexual + female, or bisexual + male. Leaves decussate or (rarely) in whorls of 3, often ericoid, +/- pungent, acuminate or acute at apex, (sub)sessile; stipular sheaths cup- or funnel-shaped, bearing minute setae or (less commonly) longer bristles on either side. Inflorescence frequently very inconspicuous, made up of flowers paired or solitary at nodes, or of mostly few-flowered cymes. Flowers bisexual, female or occasionally male. Calyx 3-5(6)-lobed, lobes leaf-like, often unequal in size. Corolla 4-7-lobed; lobes linear to +/- lanceolate, hooded, spreading to spreading-recurved (bisexual, male) or +/- erect (female); tube cylindrical to +/- narrowly funnel-shaped; in bisexual and male flowers corolla much larger than in female flowers. Stamens 4-7; anthers purplish red to dark purplish brown, exserted, dangling on long, slender, filiform filaments. Ovary 2-carpellate with 1(2) fertile, erect ovule(s); style 0; stigmas 1(2), long-exserted, hairy, purplish red, greenish grey, greyish or whitish. Fruit 1(2)-seeded, crowned by persistent calyx lobes; exocarp dehiscing into valves, releasing endocarp with enclosed seed. x = 11 (aneuploids).

Shrubs or small trees. Leaves shortly petiolate, obovate-oblong, obtuse, leathery; stipules cuspidate, deciduous. Flowers in many-flowered clusters or heads. Calyx 5-lobed, pubescent within and without; lobes linear, longer than tube; tube campanulate. Corolla 5-lobed, lobes ovate, much shorter than tube; orange to dark red, hairy; tube funnel-shaped, with ring of hairs near base. Stamens 5, arising in upper part of corolla tube, included; anthers sessile, linear, with ovate, apical appendage. Disc tumid. Ovary 2-locular, with many ovules in each locule; style terete, +/- included; stigma thick, lanceolate-elliptic, ribbed. Fruit a globose, 2-locular, many-seeded berry, crowned with persistent calyx. Seeds somewhat compressed, transversely oblong, with +/- whorled ridges. x

Large or dwarf shrubs, short-lived subshrubs or perennial herbs, male, female, bisexual, bisexual + female, or occasionally male + bisexual + female, bisexual + male, or male + female. Leaves decussate or occasionally in whorls of 3(4), often seemingly in much larger numbers at nodes, blades +/- broad and large to +/- ericoid and small, mostly narrowed to base, acute to acuminate (seldom +/- mucronate or +/- obtuse) at apex, shortly petiolate to sessile; stipular sheaths +/- cup-shaped, bearing 1 to many setae or fimbriae on either side. Inflorescence frequently leafy and inconspicuous, made up of mostly subsessile, many- to very few-flowered cymes; in dioecious taxa often sexually dimorphic (female inflorescence contracted, +/- cylinder-like). Flowers mostly subsessile, subtended by a pair of leafy bracts, male, bisexual or female, 4- or 5-merous. Calyx: lobes large, conspicuous to small, indistinct or +/- lacking. Bisexual and male flowers: corolla with tube cylindrical, broadly funnel-shaped to subcampanulate, lobes recurved, +/- lanceolate; anthers yellowish to whitish, exserted, dangling on long, slender, filiform filaments. Female flowers: corolla much smaller than in male flowers; tube cylindrical; lobes mostly erect, linear to +/- lanceolate. Ovary bicarpellate, 2-locular, in 2 species 1 carpel reduced; ovule 1 per locule; style 0 or very short; stigmas usually 2, long-exserted, hairy, greyish to greenish white, seldom purplish red. Fruit crowned by persistent calyx lobes, supported by a +/- U-shaped carpophore, dehiscing into two mericarps, each convex on dorsal side, plane to concave or sometimes hollowed out and with a prominent to inconspicuous median, longitudinal ridge on ventral side. x = 11 (aneuploids, polyploidy).

Perennial herbs or subshrubs; stems subterete, glabrous or glabrescent. Leaves sessile, slender to filiform, rigidly mucronate, margins revolute; stipule sheath mostly tubular, truncate or sometimes with 2 small cusps. Flowers isostylous or heterostylous; in terminal, sometimes also axillary cymes, rarely aggregated into corymbs, bracteate; bracts connate. Calyx 4-partite almost to base; lobes triangular. Corolla white, somewhat funnel-shaped; lobes shorter than tube, spreading, bearded on inner face to +/- middle. Stamens included in long-styled flowers, exserted in isostylous and short-styled flowers; filaments glabrous; anthers dorsifixed. Disc cushion-shaped, farinose. Ovary 2-locular, with fairly many ovules in each locule, attached to shortly stalked, shield-like placentas arising below middle of septum; style glabrous, included in short-styled flowers, exserted in long-styled and isostylous flowers; stigma lobes filiform, papillose. Fruit a globose loculicidal capsule, slightly beaked. Seeds dorsiventrally compressed, oblong, smooth, brown.