Taxonomy

The herbage of the Honeysuckles is a favourite food of goats, therefore the Latin name caprifolium (Goats’ Leaf), the French chevrefeuille, German geißblatt and Italian capri-foglio, all signifying the same. The family name is derived from the Latin Caprea, goat, which has twisted horns in certain breeds. These horns are suggested by the twisting stems of the climbing honeysuckles. The berries have been used as food for chicken.

According to Linnaeus in his Critica Botanica (1737) the name of the genus, Lonicera, was given in honour of Johan Lonitzer, latinized Lonicerus, 1499 – 1569, classical philologist; Professor of the Greek and Hebrew language in Marburg. Not Adam Lonitzer, his son, as most authors suggest.

Taxonomic division of the genus
Key for subgenera, sections and subsections:
The species fall into two well-marked subgenera: Chamaecerasus and Lonicera. Chamaecerasus distinghuised by axillary inflorescences with the flowers in pairs and the leaves free. The vast majority of this subgenus are shrubs which do not concern here and which, on the whole, are inferior in garden value to the climbers or twiners. There is just one section of this subgenera, section Nintooa, which contents climbers. The other subgenus is Lonicera with terminal, whorled inflorescences of three flowered cymes and the upper leaves usually connate.

I. Subgenus Chamaecerasus (Linn.) Rehd. 
Upright or climbing shrubs, leaves always distinctly seperate; flowers in axillary pairs, occasionally in racemose clusters at the branch tip or solitary.

Section Nintooa (Sweet) Maxim. 
Woody climbers with twining or creeping stems, twigs hollow; leaves usually evergreen. Flowers in axillary pairs, often grouped into terminal spikes or panicles. Corolla bilabiate, generally with a long slender tube. Ovary separate, rarely connate, 3(-5) celled. Fruits a berry, mostly separate, black, seldom white, yellow or red.
The section enclose about 30 species, most from Asia, from East India to China and Japan, south to Maleisian Archipelo and 1 from S.W. Europe (Spain and Sicily) and N. Africa.

*    Subsection Calcaratae Rehd. 
Corolla with a long spur near the base of the corolla tube; ovaries 5 locular, connate; prophylls connate; fruits yellow. Species: one. Type of the subsection: L. calcarata Hemsl.

**   Subsection Volubilis Hsu & H.J. Wang
Corolla without a spur, ovaries and prophylls distinct; ovaries 3 locular; corolla 3 – 20 cm long, red, orange, white or yellowish-white; fruits black, seldom white.
Species: about 30.
This subsections contains species from Mid and East Asia, with the exception of one species e.g. L. biflora from Spain, Sicilië and N. Africa.
L. acuminata, affinis, alseuosmoides, braceana, biflora, buddleioides, cambodiana, confusa, crassifolia, dasystyla, fengkaiensis, ferruginea, fulvotomentosa, giraldii, glabrata, henryi, hildebrandiana, japonica, javanica, longiflora, macrantha, macranthoides, malayana, ovata, pampaninii, pulcherrima, rhytidophylla, similis, sumatrana.
Type of the subsection: Lonicera japonica.

II. Subgenus Lonicera 
Section Lonicera
Twining shrubs with hollow twigs; leaf pairs under the inflorescences usually disk-like connate (except L. periclymenum); flowers usually in whorls of 6 at the branch tip; sessile; fruits red or orange.

*    Subsection Phenianthi (Rafin.) Rehd.
Corolla with a short, or nearly regular bilabiate limb; tube more or less bulging beneath the middle or slightly expanded; stamens inserted beneath the throat:
Type of the subsection: L. ciliosa. Species: 6
This subsection contain four species from Mexico, America to Canada, and two Chinese species, L. carnosifolia and L. subaequalis.
Species: L. arizonica, carnosifolia, ciliosa, pilosa, sempervirens, subaequalis and the hybrid L. ×brownii.

**   Subsection Lonicera 
Corolla deeply bilabiate; stamens inserted in the throat; corolla 1.5 – 8 cm long, yellow or yellow-white, red or purple.
Type of the subsectie: L. caprifolium   = lectotype.
This subsection enclosed 17 species from Mexico, Amerika to Canada, and two from China (L. cilliosissima and L. tragophylla) and a several hybrids.
Species: L. albiflora, ×americana, caprifolium, cilliossima, dioica, etrusca, ×epsomiensis, flava, ×heckrottii, hirsuta, hispidula, interrupta, ×italica, implexa, periclymenum, reticulata, ×sargentii, splendida, stabiana, subspicata, tragophylla, ×tellmanniana, yunnanensis.

***  Subsection Thoracianthae Rehd.
Prophylls at each flower pair cup-form connate, as large as the ovaries; leaf pairs all distinct.
Species: one. Type of the subsection: L. griffithii Hooker f. & Thomson