| # The Families of Angiosperms |

L. Watson and M.J. Dallwitz

### Gesneriaceae Dum.

Including Cyrtandracaceae N. Jack, Didymocarpeae (Didymocarpaceae) D. Don, Ramondiaceae (Ramondaceae) Godr. & Gren. ex Godr., Replicataceae Dulac

Habit and leaf form. Herbs (usually, sometimes slightly woody), or shrubs, or lianas (rarely). ‘Normal’ plants, or plants of very peculiar vegetative form (sometimes); sometimes remarkably neotenic (with spectacular reduction of the axis — e.g. in some Streptocarpus spp., where the plant has but one leaf which represents a cotyledon, the other cotyledon having atrophied early). Leaves (or leaf!) well developed. Plants green and photosynthesizing. With a basal aggregation of leaves, or without conspicuous aggregations of leaves. Self supporting, or epiphytic (commonly), or climbing; climbers root climbers. Mesophytic. Conspicuously heterophyllous (members of leaf pairs often very different in size), or not conspicuously heterophyllous. Leaves opposite (usually), or alternate (rarely), or whorled (rarely); ‘herbaceous’, or leathery; petiolate; simple; epulvinate. Lamina entire (usually), or dissected; rarely pinnatifid; pinnately veined; cross-venulate. Leaves exstipulate. Lamina margins entire, or serrate, or dentate. Leaf development not ‘graminaceous’. Domatia occurring in the family (Mitraria); manifested as pits.

Leaf anatomy. The leaf lamina dorsiventral. Stomata anisocytic (often very large). Hairs present; eglandular and glandular (the former simple uniseriate, often containing red or blue sap, sometimes raised on pedestals; the latter with heads 2–6 or more celled, on stalks of varying lengths). Adaxial hypodermis present (commonly), or absent. Lamina with secretory cavities (accompanying the xylem, e.g., in Rhychoglossum and Monophyllaea), or without secretory cavities (usually). Secretory cavities when present, containing oil, or containing resin; schizogenous. The mesophyll with sclerenchymatous idioblasts, or without sclerenchymatous idioblasts; usually containing crystals. The crystals variable in frequency and form, druses and solitary-prismatic. Minor leaf veins without phloem transfer cells (Aeschynanthus, Isoloma, Mitraria).

Axial (stem, wood) anatomy. Secretory cavities present (in a few genera), or absent; when present, with oil, or with resin. Cork cambium present; initially deep-seated, or initially superficial. Nodes unilacunar, or tri-lacunar, or penta-lacunar; exhibiting on either side a trace which divides, contributing the outermost lateral traces to each of the opposite leaves (exemplified in species of Alloplectus, Cyrtandra, Didymocarpus, Drymonia, Didissandra and Hemiboea), or without split-lateral traces. Primary vascular tissues usually ultimately in a cylinder, without separate bundles (the bundles generally becoming united by interfascicular prosenchymatous elements); collateral. Internal phloem absent. Cortical bundles present (a single one, in the stem ridge of Rhynchoglossum obliquum), or absent. Medullary bundles present (e.g. Monophyllaea, Rhynchoglossum), or absent. Secondary thickening developing from a conventional cambial ring.

The vessels typically small (or very small), or medium (e.g., in Drymonia); solitary and in radial multiples (the latter often of 4 or more cells). The vessel end-walls simple. The vessels without vestured pits; without spiral thickening. The axial xylem with tracheids (“vascular tracheids often present”), or without tracheids; with fibre tracheids (Coronanthera), or without fibre tracheids (usually); with libriform fibres (isially), or without libriform fibres (Coronanthera); seemingly nearly always including septate fibres. The fibres without spiral thickening. The parenchyma paratracheal (or very sparse, or absent); wood partially storied (VPI, some Cyrtandra species), or not storied (?).

Reproductive type, pollination. Unisexual flowers present, or absent. Plants hermaphrodite, or monoecious (rarely). Pollination entomophilous, or ornithophilous, or chiropterophilous.

Inflorescence, floral, fruit and seed morphology. Flowers solitary, or aggregated in ‘inflorescences’. The ultimate inflorescence units when flowers aggregated, cymose (usually), or racemose. Inflorescences terminal, or axillary, or epiphyllous. Flowers medium-sized to large; very irregular (usually), or somewhat irregular. The floral irregularity involving the perianth and involving the androecium, or involving the androecium. Flowers cyclic; tetracyclic. Free hypanthium absent. Hypogynous disk often present (when ovary superior).

Perianth with distinct calyx and corolla; 10; 2 whorled; isomerous. Calyx 5; 1 whorled; gamosepalous (usually), or polysepalous (sometimes); basally spurred, or neither appendaged nor spurred; usually valvate. Corolla 5; 1 whorled; gamopetalous; imbricate; rotate, or campanulate; bilabiate (usually), or unequal but not bilabiate, or regular (e.g. Ramonda).

Androecium 2–5. Androecial members adnate (to the corolla tube); markedly unequal (often), or all equal; free of one another (rarely), or coherent; 1 adelphous, or 2 adelphous; 1 whorled. Androecium exclusively of fertile stamens, or including staminodes. Staminodes 1–3 (replacing fertile members); in the same series as the fertile stamens; representing the posterior median member, or the posterior-lateral pair, or the posterior median member and the posterior-lateral pair (?). Fertile stamens representing the anterior-lateral pair, or the posterior-lateral pair and the anterior-lateral pair. Stamens 2, or 4(–5) (the posterior member occasionally present — e.g. Ramonda); inserted near the base of the corolla tube, or midway down the corolla tube, or in the throat of the corolla tube; commonly didynamous; reduced in number relative to the adjacent perianth (usually), or isomerous with the perianth; oppositisepalous. Anthers cohering, or connivent, or separate from one another (rarely); dorsifixed to basifixed, or basifixed; dehiscing via longitudinal slits; appendaged (e.g., the connective with two diverging short horns in Codonoboea), or unappendaged. Endothecium developing fibrous thickenings. Anther epidermis persistent. Microsporogenesis simultaneous. The initial microspore tetrads tetrahedral, or decussate. Anther wall initially with one middle layer; of the ‘dicot’ type. Tapetum glandular. Pollen grains aperturate; (2–)3(–6) aperturate; colporate (usually, or colporoidate), or rugate; 2-celled (in 6 genera).

Gynoecium 2 carpelled. The pistil 1 celled, or 2 celled (rarely). Gynoecium syncarpous; synstylovarious to eu-syncarpous; superior to inferior. Ovary unilocular (mostly, by contrast with Scrophulariaceae), or plurilocular (e.g., Streptocarpus, Petrocosmea, Saintpaulia); 1 locular (usually), or 2 locular (through meeting of the two placentae). Gynoecium median. Epigynous disk when ovary inferior, commonly present. Styles 1; attenuate from the ovary; apical. Stigmas 1–2; 1–2 lobed; wet type, or dry type; papillate; Group II type, or Group III type. Placentation usually parietal; when bilocular, axile. Ovules in the single cavity usually (i.e. when unilocular), 15–100 (i.e. ‘many’); when bilocular 10–50 per locule (i.e. ‘many’); funicled, or sessile; non-arillate; anatropous; unitegmic; tenuinucellate. Endothelium differentiated (proximally only). Embryo-sac development Polygonum-type. Antipodal cells formed; 3; not proliferating; very ephemeral. Synergids slender, sometimes with long, tapering tips entering the micropyle and extending through its length. Endosperm formation cellular. Endosperm haustoria present; chalazal and micropylar. Embryogeny onagrad.

Fruit fleshy, or non-fleshy; dehiscent (usually), or indehiscent; a capsule (usually), or a berry (infrequently). Capsules loculicidal (usually), or valvular (sometimes), or septicidal (rarely). Seeds endospermic, or non-endospermic (Cyrtandroideae). Endosperm when present, oily. Seeds small. Cotyledons 2, or 1–2 (one being sometimes reduced or absent, and in some Streptocarpus species, the other enlarging to such an extent as to constitute virtually the whole plant, bearing flowers on its midrib). Embryo achlorophyllous (1/1); straight.

Seedling. Germination phanerocotylar.

Physiology, phytochemistry. C3, or CAM. C3 physiology recorded directly in Saintpaulia. CAM recorded directly in Codonanthe. Anatomy non-C4 type (Didymocarpus). Not cyanogenic. Alkaloids absent (one species). Anthraquinones detected (Streptocarpus); derived from shikimic acid. Verbascosides detected (many genera). Cornoside detected (several genera). Iridoids not detected. Saponins/sapogenins absent. Proanthocyanidins absent. Flavonols absent. Ellagic acid absent (4 species, 3 genera). Aluminium accumulation not found.

Special distinguishing feature. The funicles not as in Acanthaceae.

Geography, cytology. Temperate (a few), sub-tropical to tropical (mostly). Pantropical, a few temperate. X = 4–17(+). Supposed basic chromosome number of family: 8, or 9.

Taxonomy. Subclass Dicotyledonae; Tenuinucelli. Dahlgren’s Superorder Lamiiflorae; Scrophulariales. Cronquist’s Subclass Asteridae; Scrophulariales. APG III core angiosperms; core eudicot; Superorder Asteranae; lamiid. APG IV Order Lamiales.

Species 2000. Genera about 140; Achanthonema, Achimenes, Aeschynanthus, Agalmyla, Allocheilos, Alloplectus, Allostigma, Alsobia, Ancylostemon, Anetanthus, Anna, Anodiscus, Asteranthera, Beccarinda, Bellonia, Besleria, Boea, Boeicca, Bournea, Briggsia, Briggsiopsis, Bucinellina, Calcareoboea, Capanea, Cathayanthe, Centrosolenia, Championia, Chirita, Chiritopsis, Chrysothemis, Cobananthus, Codonanthe, Codonanthopsis, Codonoboea, Colpogyne, Columnea, Conandron, Corallodiscus, Coronanthera, Corytoplectus, Crantzia, Cremosperma, Cubitanthus, Cyrtandra, Cyrtandromoea, Dayaoshania, Deinocheilos, Depanthus, Diastema, Didissandra, Didymocarpus, Didymostigma, Dolicholoma, Drymonia, Dorcoceras, Episcia, Epithema, Eucodonia, Fieldia, Gasteranthus, Gesneria, Gloxinia, Gloxinopsis, Goyazia, Gyrocheilos, Gyrogyne, Haberlea, Hemiboea, Hemiboeopsis, Henckelia, Heppiella, Hexatheca, Hypocyrta, Isometrum, Jancaea, Koellikeria, Kohleria, Lagarosolen, Lembocarpus, Lenbrassia, Leptobaea, Liebigia, Lietzia, Linnaeopsis, Loxocarpus, Loxonia, Loxostigma, Lysionotus, Metabriggsia, Metapetrocosmea, Micraeschynanthus, Microchirita, Mitraria, Monophyllaea, Monopyle, Moussonia, Napeanthus, Nautilocalyx, Negria, Nematanthus, Neomortonia, Niphaea, Nodonema, Oerstedina, Opithandra, Orchadocarpa, Oreocharis, Ornithoboea, Oxychlamys, Paliavana, Paraboea, Paradrymonia, Parakohleria, Pearcea, Pentaraphia, Petrocodon, Petrocosmea, Pheidonocarpa, Phinaea, Phyllobaea, Platyadenia, Primulina, Pseudochirita, Ramonda, Reldia, Resia, Rhabdothamnopsis, Rhabdothamnus, Rhoogeton, Rhynchoglossum, Rhynchotechum, Rhytidophyllum, Ridleyandra, Rufodorsia, Saintpaulia, Sanango, Sarmienta, Schistolobos, Schizoboea, Sepikea, Sinningia, Smithiantha, Solenophora, Stauranthera, Streptocarpus, Tapeinotes, Tengia, Tetraphyllum, Thamnocharis, Titanotrichum, Trachystigma, Tremacron, Trisepalum, Tylopsacas, Vanhouttea, Whytockia.

Illustrations. • Le Maout and Decaisne: Ramonda. • Le Maout and Decaisne: Gesneria, Dircaea (= Corytholoma), Moussonia (= Isoloma), "Tidaea". • Le Maout and Decaisne: Ligeria (= Sinningia), Achimenes, Pentarhaphia. • Le Maout and Decaisne: Aeschynanthus, Columnea, Nematanthus, Streptocarpus. • Le Maout and Decaisne: Alloplectus, Tapeinotes (= Sinningia), Hypocyrta. • Achimenes erecta (as A. rosea): Bot. Reg. 65, 1841. • Achimenes longiflora: Bot. Reg. 19, 1842. • Achimenes longiflora: Bot. Mag. 69 (1842). • Achimenes mexicana (as Scheeria): Bot. Mag. 79 (1853). • Achimenes skinneri (as A. hirsuta): Bot. Reg. 29, 55 (1843). • Aeschynanthus albidus (as A. purpurascens): Bot. Mag. 72 (1846). • Aeschynanthus cordifolius: Bot. Mag. 85 (1859). • Aeschynanthus fulgens: Bot. Mag. 82 (1856). • Aeschynanthus lobbianus: Bot. Mag. 72 (1846). • Aeschynanthus obconica: Bot. Mag. 120 (1894). • Aeschynanthus parasiticus (as A. grandiflorus): Bot. Reg. 49, 1841. Aeschynanthus parasiticus. 1 and 2, transverse and longitudinal sections of the ovary, showing the unusual variation on “unilocular with parietal placentation”. • Aeschynanthus pulcher (as A. javanicus): Bot. Mag. 76 (1850). • Aeschynanthus ramosissimus: as A. maculatus, Bot. Reg. 28, 1841. • Aeschynanthus speciosus: Bot. Mag. 73 (1847). • Aeschynanthus tricolor: Bot. Mag. 84 (1858). • Agalmyla elongata (as Dichrotrichum ternateum): Bot. Mag. 110 (1884). • Agalmyla parasitica (as A. staminea): Bot. Mag. 94 (1868). • Alsobia punctata (as Drymonia): Bot. Mag. 70 (1844). • Besleria lutea (as B. imray): Bot. Mag. 104 (1878). • Besleria leucostoma (as Hypocyrta): Bot. Mag. 73 (1847). • Besleria umbrosa: Martius, Nova Gen. et Spec. Pl. Brasiliensium 3 (1829). • Briggsia longipes (as Didissandra): Hook. Ic. Pl. 24 (1895). • Primulina dryas (as Chirita sinensis): Bot. Reg. 1844, 59. Primulina dryas. 1, corolla split open to show the layout of the androecium. 2, the gynoecium. 3, transverse section of the ovary, showing the patttern of placentation typical of the family. • Centrosolenia densa (as Episcia): Bot. Mag. 122 (1896). • Codonoboea crinita (as Didymocarpus): Bot. Mag. 77 (1851). • Codonoboea malayana (as Didymocarpus): Bot. Mag. 123 (1897). • Columnea microcalyx (as C. gloriosa): Bot. Mag. 137 (1911). • Columnea minor (as Trichantha): Bot. Mag. 90 (1864). • Columnea repens (as Alloplectus): Bot. Mag. 72 (1846). • Columnea sanguinea (as C. aureonitens): Bot. Mag. 73 (1847). • Columnea scandens: Bot. Mag. 85 (1859). • Columnea schiediana: Goebel. • Conandron ramondioides: Bot. Mag. 106 (1880). • Corytoplectus schlimii (as Hypocyrta pulchra): Bot. Mag. 122 (1896). • Crantzia tigrina (as Heintzia): Bot. Mag. 80 (1854). • Dorcoceras hygrometricum (as Baea): Bot. Mag. 105 (1879). • Drymonia peltata (as Alloplectus): Bot. Mag. 103 (1877). • Drymonia serratula, as D. calcarata: Martius, Nova Gen. et Spec. Pl. Brasiliensium 3 (1829). • Drymonia serratula: as D. bicolor, Bot. Reg. XXIV, 4 (1838). Drymonia serratula. 1, ovary, with oblique hypogynous disk and dorsal gland (detail of the stigma is to the right). 2, transverse section of the ovary, showing placentation. • Episcia cupreata (as Achimenes): Bot. Mag. 73 (1847). • Episcia erythropus: Bot. Mag. 102 (1876). • Episcia lilacina (as E. chontalensis): Bot. Mag. 97 (1971). • Episcia melittifolia: Bot. Mag. 79 (1853). • Episcia reptans: Martius, Nova Gen. et Spec. Pl. Brasiliensium 3 (1829). • Episcia reptans (as E. fulgida): Bot. Mag. 100 (1874). • Eucodonia verticillata (as Scheeria lanata): Bot. Mag. 83 (1857). • Fieldia australis: Bot. Mag. 84 (1858). • Gesneria cinnabarina: Bot. Mag. 84 (1858). • Gesneria faucialis: as Gesnera, Bot. Reg. 1785, 1836. • Gesneria lateritia: as Gesnera, Bot. Reg. 1950, 1837. • Gesneria pumila subsp. neglecta, as Conradia: Hook. Ic. Pl. 9 (1852). • Gloxinia erinoides (as Achimenes argyostigma): Bot. Mag. 71 (1845). • Gloxiniopsis racemosa (as Monopyle): Bot. Mag. 102 (1876). • Haberlea rhodopensis: Bot. Mag. 108 (1882). • Henckelia communis (as Chirita zeylanica): Bot. Mag. 71 (1845). • Henckelia humboldtiana (as Didymocarpus): Bot. Mag. 79 (1853). • Henckelia humboldtiana (as Didymocarpus primulaefolia): Bot. Mag. 86 (1860). • Henckelia speciosa (as Chirita trailliana): Bot. Mag. 143 (1917). • Henckelia walkerae: Bot. Mag. 73 (1847). • Isoloma longifolium: as Gesnera longifolia, Bot. Reg. 40, 1842. • Kohleria amabilis (as Tydaea): Bot. Mag. 83 (1857). • Kohleria hirsuta (as Isoloma erianthum): Bot. Mag. 129 (1903). • Kohleria inaequalis, as Tydaea warscewiczii: Lemaire, Illustr. Horticole (1854). • Kohleria inaequalis var. ocellata (as Achimenes ocellata): Bot. Mag. 74 (1848). • Kohleria spicata (as Gesneria schiediana): Bot. Mag. 71 (1845). • Kohleria warszewiczii (as Sciodacalyx): Bot. Mag. 81 (1855). • Liebigia barbata (as L. speciosa): Bot. Mag. 73 1847). • Lysionotus serratus: Bot. Mag. 107 (1881). • Microchirita rupestris (as Chirita): Bot. Mag. 136 (1910). • Nautilocalyx bicolor (as Episcia): Bot. Mag. 74 (1848). • Nautilocalyx bracreatus (as Centrosolenia bractescens): Bot. Mag. 78 (1852). • Nautilocalyx lynchii (as Alloplectus): Bot. Mag. 118 (1892). • Nematanthus crassifolius subsp. chloronema (as N. chloronema): Bot. Mag. 70 (1844). • Nematanthus hirsutus, as Hypocyrta: Martius, Nova Gen. et Spec. Pl. Brasiliensium 3 (1829). • Nematanthus lanceolatus (as Alloplectus concolor): Bot. Mag. 74 (1848). • Nematanthus sericeus (as Hypocyrta strigillosa): Bot Mag. 69 (1843). • Nematanthus strigillosus (as Hypocyrta glabra): Bot. Mag. 74 (1848). • Niphaea oblonga: Bot. Reg. 5, 1842. Niphaea oblonga. 1, corolla tube openened to show the androecium. 2 and 3, vertical and transverse sections of the ovary. • Oreocharis forrestii: Curtis Bot. Mag. 143 (1917). • Ornithoboea lacei: Bot. Mag. 141 (1915). • Paradrymonia maculata (as Episcia): Bot. Mag. 116 (1890). • Pearcea hypocyrtiflora (as Gloxinia): Bot. Mag. 93 (1867). • Pentaraphia cubensis: Bot. Mag. 81 (1855). • Pentaraphia longiflora: Bot. Mag. 120 (1894). • Petrocosmea sinensis (as Petrocosmia): Hook. Ic. Pl. 18 (1887). • Phinaea albolineata: Bot. Mag. 73 (1847). • Primulina depressa (as Chirita): Bot. Mag. 118 (1892). • Primulina tabacum (as P. sinensis): Curtis Bot. Mag. 116 (1890). • Rhabdothamnopsis sinensis: Hook. Ic. Pl. 28 (1905). • Rhabdothamnus solandri: Bot. Mag. 131 (1905). • Rhynchoglossum obliquum (as R. zeylanicum): Bot. Mag. 71 (1845). • Rhynchotechum ellipticum: Bot. Mag. 96 (1870). • Ridleyandra rufa (as Didissandra): Hook. Ic. Pl. 15 (1883–1885). • Saintpaulia ionantha: Bot. Mag. 121 (1895). • Sanango racemosum (as S. durum): Bunting and Duke, Ann. Miss. Bot. Gard. 48 (161). • Sarmienta scandens (as S. repens): Bot. Mag. 109 (1883). • Sinningia concinna (as Stenogastra): Bot. Mag. 87 (1861). • Sinningia magnifica (as Gesneria marchii): Bot. Mag. 66 (1839). • Sinningia tuberosa, as Gesneria: Martius, Nova Gen. et Spec. Pl. Brasiliensium 3 (1829). • Sinningia barbata and S. pusilla, as Tapina spp.: Martius, Nova Gen. et Spec. Pl. Brasiliensium 3 (1829). • Sinningia sceptrum, as Gesneria: Martius, Nova Gen. et Spec. Pl. Brasiliensium 3 (1829). • Sinningia velutina: Bot. Mag. 72 (1846). • Smithiantha multiflora (as Naegelia): Bot. Mag. 84 (1858). • Smithiana zebrina (as Naegelia): Bot. Reg. 16, 1842. • Stauranthera grandifolia: Bot. Mag. 89 (1863). • Streptocarpus caulescens: Bot. Mag. 111 (1885). • Streptocarpus cooperi: Thonner. • Streptocarpus cyaneus: Bot. Mag. 139 (1913). • Streptocarpus dunnii: Bot. Mag. 112 (1886). • Streptocarpus galpinii: Bot. Mag. 118 (1892). • Streptocarpus grandis: Bot. Mag. 131 (1905). • Streptocarpus kirkii: Bot. Mag. 110 (1884). • Streptocarpus mahoni: Bot. Mag. 128 (1902). • Streptocarpus parviflorus: Bot. Mag. 108 (1882). • Streptocarpus parviflorus: Bot. Mag. 115 (1889). • Streptocarpus polyanthus: Bot. Mag. 81 (1855). • Streptocarpus rexii (as Didymocarpus): Bot. Mag. 57 (1830). • Streptocarpus saundersii: Bot. Mag. 87 (1861). • Streptocarpus strigosus (as Acanthonema): Bot. Mag. 88 (1862). • Tapeinotes carolinae: Bot. Mag. 93 (1867). • Titanotrichum oldhamii: Hook. Ic. Pl. 30 (1911).

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, genera included in each family, and classifications (Dahlgren; Dahlgren, Clifford, and Yeo; Cronquist; APG). See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 1992 onwards. The families of flowering plants: descriptions, illustrations, identification, and information retrieval. Version: 8th June 2026. delta-intkey.com’.

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