Lasianthus

Lasianthus View in CoL

Lasianthus Jack (1823) View in CoL 125, nom. cons.; Blume (1826 –1827) 995; Spreng. (1830) 94; Wight (1846) 498; Miq. (1857) 314; Hook.f. (1873) 129; Kurz (1877) 30; Hiern (1877) 228; Hook.f. (1880) 178; K.Schum. (1891) 120; Prain (1903) 576; Ridl. (1923a) 149; Pit. (1924) 371; Valeton (1927) 105; Craib (1934) 207; Fl. Hainan 3 (1974) 333;T.S.Liu & J.M.Chao (1964) 118; Bakh.f. (1965) 335; K.M. Wong (1988) 367; Deb & M.Gangop. (1991) 270; H. Zhu (1994) 49;(2001b) 124;(2002) 69. — Type: Lasianthus cyanocarpus Jack View in CoL (typ. cons.).

Dasus Lour.(1790) View in CoL 141, nom. rej. — Type: Dasus verticillata Lour. (= Lasianthus verticillatus (Lour.) Merr. View in CoL ).

Mephitidia Reinw.ex Blume (1823) View in CoL 51. — Type: Mephitidia hexandra Blume View in CoL (= Lasianthus hexandrus (Blume) Blume ).

Litosanthes Blume (1823) View in CoL 22;(1826–1827) 994. — Type: Litosanthes biflora Blume. View in CoL

Santia Wight & Arn. (1834) View in CoL 422, nom. illeg., non Santia Savi 1799 View in CoL . — Type: Santia venulosa Wight & Arn. View in CoL (= Lasianthus venulosus (Wight & Arn.) Wight View in CoL ).

Subshrubs, shrubs, or rarely small trees, foetid or not. Branches and branchlets terete, sometimes compressed, rarely fistulous; lenticels inconspicuous or conspicuous. Leaves opposite, distichous, usually thinly coriaceous or chartaceous; apex acuminate, acute or cuspidate; base acute to rounded or cordate; midrib flat, depressed or slightly prominent above, usually prominent beneath; nerves generally prominent beneath, ascending at an angle of more than 45°, curved to the margin or joining the nerves above at margin; nervules parallel or reticulate. Stipules interpetiolar, usually persistent, well developed or inconspicuous, triangular, lanceolate, ovate or oblong; apex acute or obtuse. Inflorescences axillary, rarely supraaxillary, opposite, sessile, compact or cymes with peduncles, several-flowered to many-flowered; peduncles conspicuous or compressed, stout to extremely congested; bracts persistent or not, well developed or absent. Flowers small, white, sessile or pedicellate, in clusters or peduncled cymes axillary and paired at the nodes; calyx campanulate, with 3 –6 teeth or lobes, rarely with cupular limb truncate at apex, persistent on fruit; corolla funnel-form or salver-shaped, several mm long to the maximum of 2.5 cm long, glabrous or hairy outside; the throat usually villous inside; the lobes 4–6, valvate or imbricate in bud; sta- mens 4–6, inserted on the throat of the corolla; filaments short; the anthers linear or oblong, dorsifixed, included or exserted; style linear, with 3 – 9 linear or lanceolate stigmas lobes; ovary 3 –9-celled; ovules 1 in each cell, basal, erect. Fruit drupes small, pulpy, blue, or rarely white, black or red, usually globose, smooth or warty, rounded or ridged; pyrenes 2 – 9, thick walled, smooth, warty or sulcate on the abaxial face, usually triangular in transverse section.

Distribution — More than 180 species in tropical areas of the world, and centred in tropical Asia. There are more than 160 species in tropical Asia, c. 20 species in Africa, 1 in Australia and 3 in tropical America.

Note — Hooker’s (1880) infrageneric system has been com- monly accepted although there is not an exclusive character for any of the sections. Stipules, bracts and peduncles, which are key characteristics to separate sections in Hooker’s system, vary from species to species gradually in size and shape. However, some correlation among these characteristics can be seen indeed. Large stipules (large enough to cover or partly cover the inflorescence) are correlated with the sessile inflorescence and numerous bracts except for two species in which the bracts are reduced. The sect. Stipulares so defined seems a natural group. The sect. Nudiflorae , which has sessile or subsessile inflorescences and inconspicuous bracts except one species with very short peduncles, can be recognised as a loose group. The sect. Lasianthus , which has sessile cymes accompanied by conspicuous bracts, cannot be clearly separated from the sect. Pedunculatae , which has peduncled cymes, because there is a group of species with conspicuous peduncles accompanied by conspicuous bracts, such as L. moonii , L. pendulus , L. rhinocerotis . Here we therefore reduce the sect. Pedunculatae to the sect. Lasianthus .

Key to the sections

1. Stipules quite large, ovate, oblong-ovate or triangular-ovate, coriaceous with membranaceous margin or membranaceous, partly or completely covering the sessile cymes.................................. sect. I. Stipulares View in CoL

1. Stipules large or small, triangular, lanceolate, oblong, rarely ovate, never large enough to cover or partly cover cymes 2

2. Bracts conspicuous, linear-lanceolate, ovate, cordate or leaf-like, more that 3 mm long....... sect. II. Lasianthus View in CoL

2. Bracts inconspicuous or absent, or minute, linear, usually less than 3 mm long.............. sect. III. Nudiflorae View in CoL