Description from Flora of China
Trees, shrubs, woody climbers, or herbs, sometimes epiphytic, sometimes with axillary spines or tendrils. Leaves opposite, occasionally alternate, rarely verticillate, fasciculate, or in a whorl; stipules usually present, often reduced to lines connecting petiole bases, sometimes reduced to petiolar ocrea or a connate leaf-sheath; leaf blade usually entire, pinnately veined or 3--7-veined from base. Flowers in cymes, these often grouped into thyrses; cymes sometimes umbel-like, scorpioid or reduced to a single flower; bracts usually small. Flowers usually bisexual. Calyx 4- or 5-lobed; lobes free or connate, mostly persistent, imbricate or valvate. Corolla sympetalous; lobes 4 or 5(--16), valvate, imbricate or contorted in bud. Stamens inserted on corolla, included to exserted, equal in number to corolla lobes and alternating with them or sometimes fewer; filaments free, much shorter to much longer than anthers; anthers basifixed, 2--4-locular, dehiscing introrsely or extrorsely by longitudinal slits, base slightly to deeply parted. Disc ring-shaped or not. Ovary superior or rarely semi-inferior, (1- or)2(--4)-locular, placentation axillary or parietal; ovules 1 to many per locule. Style simple, terminal, persistent or deciduous; stigma usually capitate, entire or shortly 2--4-cleft. Fruit a capsule, berry, or drupe, 1- to many-seeded. Seeds sometimes winged; endosperm fleshy or horny; embryo minute, straight; cotyledons small.
Some 29 genera and about 500 species: mainly in tropical and subtropical regions of the world, absent from Europe; eight genera and 45 species (ten endemic) in China.
Li Ping-tao in Chang Mei-chen & Qiu Lian-qing, eds. 1992. Loganiaceae. Fl. Reipubl. Popularis Sin. 61: 223-309.
(Authors: Li Ping-tao; Antony J. M. Leewenberg)