Gesneriaceae, the gesneriad family,[3][4] is a family of flowering plants consisting of about 152 genera and ca. 3,540 species[5] in the tropics and subtropics of the Old World (almost all Didymocarpoideae) and the New World (most Gesnerioideae), with a very small number extending to temperate areas. Many species have colorful and showy flowers and are cultivated as ornamental plants.

Gesneriaceae
Streptocarpus ionanthus (an African violet) - a common household plant and a member of the family
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Lamiales
Family: Gesneriaceae
Rich. & Juss. in DC, nom. cons.[1][2]
Subfamilies

See text.

Haberlea rhodopensis flowers
Corytoplectus capitatus is a large plant with fruit that are black berries.
Ramonda myconi fruit are dry dehiscent capsules.

Etymology

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The family name is based on the genus Gesneria, which honours Swiss naturalist and humanist Conrad Gessner.[6]

Description

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Most species are herbaceous perennials or subshrubs but a few are woody shrubs or small trees. The phyllotaxy is usually opposite and decussate, but leaves have a spiral or alternate arrangement in some groups. As with other members of the Lamiales the flowers have a (usually) zygomorphic corolla whose petals are fused into a tube and there is no one character that separates a gesneriad from any other member of Lamiales.[4] Gesneriads differ from related families of the Lamiales in having an unusual inflorescence structure, the "pair-flowered cyme", but some gesneriads lack this characteristic, and some other Lamiales (Calceolariaceae and some Scrophulariaceae) share it. The ovary can be superior, half-inferior or fully inferior, and the fruit a dry or fleshy capsule or a berry. The seeds are always small and numerous. Gesneriaceae have traditionally been separated from Scrophulariaceae by having a unilocular rather than bilocular ovary, with parietal rather than axile placentation.

Taxonomy

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"Gesneriaceae" is a conserved name (nom. cons.),[2] meaning that although alternative, less well used names for the family were published earlier, the International Code of Nomenclature for algae, fungi, and plants specifies this as the name to be used. It was published by Louis Claude Richard and Antoine Laurent de Jussieu in 1816.[1] In 1829, Barthélemy Dumortier divided the family into two tribes, based on the number of stamens.[7] However, the only genus he placed in his two-stamen tribe, Columellia, is now placed in the separate family Columelliaceae.[8] Dumortier's publication has been treated as the first for the family by some sources.[9]

Botanists who have made significant contributions to the systematics of the family are George Bentham, Robert Brown, B.L. Burtt, C.B. Clarke, Olive Mary Hilliard, Joseph Dalton Hooker, William Jackson Hooker, Karl Fritsch, Elmer Drew Merrill, Harold E. Moore Jr., John L. Clark, Conrad Vernon Morton, Henry Nicholas Ridley, Laurence Skog, W.T. Wang, Anton Weber, and Hans Wiehler.[citation needed] The Gesneriad Society is an international horticultural society devoted to the promotion, cultivation, and study of Gesneriaceae.[10]

Phylogeny

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From about 1997 onwards, molecular phylogenetic studies led to extensive changes in the classification of the family Gesneriaceae and its genera, many of which have been re-circumscribed or synonymized. New species are still being discovered, particularly in Asia, and may further change generic boundaries. A consensus phylogeny used to build classifications of the family in 2013 and 2020 is shown below (to the level of tribes). The family Calceolariaceae is shown as the sister to Gesneriaceae.[11][12]

Peltanthera

Calceolariaceae

Gesneriaceae

Sanangoideae (Sanango)

Gesnerioideae

Titanotricheae (Titanotrichum)

Napeantheae (Napeanthus)

Beslerieae

Coronanthereae

Gesnerieae

Didymocarpoideae

Epithemateae

Trichosporeae

A phylogenomic study published in 2021 which used 418 nuclear genes confirmed the monophyly of all the subfamilies and tribes. It resolved Peltanthera as sister to a clade of Calceolariaceae and Gesneriaceae. Within the Gesnerioideae, Napeantheae rather than Titanotricheae was found to be sister to the remaining tribes. The position of Titanotricheae varied according to the method used to build the cladogram, which the authors suggested was due to incomplete lineage sorting following rapid divergence. The phylogenetic position of Titanotrichum remains unsettled.[13]

Concatenation-based Coalescent-based
Gesnerioideae

Napeantheae (Napeanthus)

Titanotricheae (Titanotrichum)

Beslerieae

Coronanthereae

Gesnerieae

Gesnerioideae

Napeantheae (Napeanthus)

Beslerieae

Titanotricheae (Titanotrichum)

Coronanthereae

Gesnerieae

The genus Sanango has not always been included in Gesneriaceae. However, molecular phylogenetic studies published up to and including 2021 suggest that it does belong in the family as the most basal member, and it is placed in its own subfamily. The studies also show the genus Peltanthera to be outside the family,[12][13] although some sources still place it within the Gesneriaceae.[14] The genus Rehmannia has also sometimes been included in the family but is now referred to the family Orobanchaceae.[15]

No single morphological feature absolutely divides two main subfamilies (i.e. forms a uniform synapomorphy). Gesnerioideae seedlings have normal cotyledons of the same size and shape (isocotylous). The cotyledons of Didymocarpoideae are usually, but not always, eventually different in size and shape (anisocotylous). One cotyledon ceases to grow and withers away, while the other continues to grow, and may even form a very large leaf that is the only one the plant has (Monophyllaea, some Streptocarpus). Gesnerioideae flowers usually have four fertile stamens, rarely two or five. Didymocarpoideae flowers usually have two fertile stamens, less often four, rarely one or five.[12]

Subfamilies and genera

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Rhynchoglossum notonianum

On the basis of molecular phylogenetic, morphological and biogeographical differences, the family has been divided into two major subfamilies: subfamily Didymocarpoideae (formerly Cyrtandroideae) with all but one species from the Old World, and subfamily Gesnerioideae native from the Americas west through the Pacific to Australia and southeastern China. The genus Sanango is placed in its own subfamily, Sanangoideae. The two main subfamilies are further divided into tribes and subtribes.[12]

Genera accepted by Plants of the World Online (PoWO) as of August 2024 are listed below,[16] together with their placement in a subfamily and tribe by Weber et al. (2020).[12] Three genera are listed by PoWO but not by Weber et al.: Coptocheile Hoffmanns. (now treated as a synonym of Sinningia), Parakohleria Wiehler (now included in Pearcea) and Peltanthera Benth. (excluded from Gesneriaceae by molecular phylogenetic studies).

Gesneriaceae genera
Genus Subfamily: Tribe
Achimenes P.Browne Gesnerioideae: Gesnerieae
Aeschynanthus Jack Didymocarpoideae: Trichosporeae
Agalmyla Blume Didymocarpoideae: Trichosporeae
Allocheilos W.T.Wang Didymocarpoideae: Trichosporeae
Alloplectus Mart. Gesnerioideae: Gesnerieae
Allostigma W.T.Wang Didymocarpoideae: Trichosporeae
Alsobia Hanst. Gesnerioideae: Gesnerieae
Amalophyllon Brandegee Gesnerioideae: Gesnerieae
Anetanthus Hiern ex Benth. & Hook.f. Gesnerioideae: Beslerieae
Anna Pellegr. Didymocarpoideae: Trichosporeae
Asteranthera Hanst. Gesnerioideae: Coronanthereae
Beccarinda Kuntze Didymocarpoideae: Trichosporeae
Bellonia L. Gesnerioideae: Gesnerieae
Besleria Plum. ex L. Gesnerioideae: Beslerieae
Billolivia D.J.Middleton Didymocarpoideae: Trichosporeae
Boea Comm. ex Lam. Didymocarpoideae: Trichosporeae
Boeica C.B.Clarke Didymocarpoideae: Trichosporeae
Bopopia Munzinger & J.R.Morel Gesnerioideae: Coronanthereae
Bournea Oliv. Didymocarpoideae: Trichosporeae
Briggsiopsis K.Y.Pan Didymocarpoideae: Trichosporeae
Cathayanthe Chun Didymocarpoideae: Trichosporeae
Centrosolenia Benth. Gesnerioideae: Gesnerieae
Championia Gardner Didymocarpoideae: Trichosporeae
Chautemsia A.O.Araujo & V.C.Souza Gesnerioideae: Gesnerieae
Chayamaritia D.J.Middleton & Mich.Möller Didymocarpoideae: Trichosporeae
Christopheria J.F.Sm. & J.L.Clark Gesnerioideae: Gesnerieae
Chrysothemis Decne. Gesnerioideae: Gesnerieae
Cobananthus Wiehler) Gesnerioideae: Gesnerieae
Codonanthe (Mart.) Hanst. Gesnerioideae: Gesnerieae
Codonanthopsis Mansf. Gesnerioideae: Gesnerieae
Codonoboea Ridl. Didymocarpoideae: Trichosporeae
Columnea Plum. ex L. Gesnerioideae: Gesnerieae
Conandron Siebold & Zucc. Didymocarpoideae: Trichosporeae
Corallodiscus Batalin Didymocarpoideae: Trichosporeae
Coronanthera Vieill. ex C.B.Clarke Gesnerioideae: Coronanthereae
Corytoplectus Oerst. Gesnerioideae: Gesnerieae
Crantzia Scop. Gesnerioideae: Gesnerieae
Cremersia Feuillet & L.E.Skog Gesnerioideae: Gesnerieae
Cremosperma Benth. Gesnerioideae: Beslerieae
Cremospermopsis L.E.Skog & L.P.Kvist Gesnerioideae: Beslerieae
Cyrtandra J.R.Forst. & G.Forst. Didymocarpoideae: Trichosporeae
Damrongia Kerr ex Craib Didymocarpoideae: Trichosporeae
Depanthus S.Moore Gesnerioideae: Coronanthereae
Diastema Benth. Gesnerioideae: Gesnerieae
Didissandra C.B.Clarke Didymocarpoideae: Trichosporeae
Didymocarpus Wall. Didymocarpoideae: Trichosporeae
Didymostigma W.T.Wang Didymocarpoideae: Trichosporeae
Dorcoceras Bunge Didymocarpoideae: Trichosporeae
Drymonia Mart. Gesnerioideae: Gesnerieae
Emarhendia Kiew, A.Weber & B.L.Burtt Didymocarpoideae: Trichosporeae
Episcia Mart. Gesnerioideae: Gesnerieae
Epithema Blume Didymocarpoideae: Epithemateae
Eucodonia Hanst. Gesnerioideae: Gesnerieae
Fieldia A.Cunn. Gesnerioideae: Coronanthereae
Gasteranthus Benth. Gesnerioideae: Beslerieae
Gesneria Plum. ex L. Gesnerioideae: Gesnerieae
Glabrella Mich.Möller & W.H.Chen Didymocarpoideae: Trichosporeae
Glossoloma Hanst. Gesnerioideae: Gesnerieae
Gloxinella (H.E.Moore) Roalson & Boggan Gesnerioideae: Gesnerieae
Gloxinia L'Hér. Gesnerioideae: Gesnerieae
Gloxiniopsis Roalson & Boggan Gesnerioideae: Gesnerieae
Goyazia Taub. Gesnerioideae: Gesnerieae
× Goydirola A.O.Araujo & M.Peixoto
(Goyazia × Mandirola)
Gesnerioideae: Gesnerieae
Gyrocheilos W.T.Wang Didymocarpoideae: Trichosporeae
Gyrogyne W.T.Wang Didymocarpoideae: Epithemateae
Haberlea Friv. Didymocarpoideae: Trichosporeae
Hemiboea C.B.Clarke Didymocarpoideae: Trichosporeae
Henckelia Spreng. Didymocarpoideae: Trichosporeae
Heppiella Regel Gesnerioideae: Gesnerieae
Hexatheca C.B.Clarke Didymocarpoideae: Trichosporeae
Jerdonia Wight Didymocarpoideae: Trichosporeae
Kaisupeea B.L.Burtt Didymocarpoideae: Trichosporeae
Kohleria Regel Gesnerioideae: Gesnerieae
Lampadaria Feuillet & L.E.Skog Gesnerioideae: Gesnerieae
Langbiangia Luu, C.L.Hsieh & K.F.Chung Didymocarpoideae: Trichosporeae: Didymocarpinae
Lembocarpus Leeuwenb. Gesnerioideae: Gesnerieae
Lenbrassia G.W.Gillett Gesnerioideae: Coronanthereae
Leptoboea Benth. Didymocarpoideae: Trichosporeae
Lesia J.L.Clark & J.F.Sm. Gesnerioideae: Gesnerieae
Liebigia Endl. Didymocarpoideae: Trichosporeae
Litostigma Y.G.Wei, F.Wen & Mich.Möller Didymocarpoideae: Trichosporeae
Loxocarpus R.Br. Didymocarpoideae: Trichosporeae
Loxonia Jack Didymocarpoideae: Epithemateae
Loxostigma C.B.Clarke Didymocarpoideae: Trichosporeae
Lysionotus D.Don Didymocarpoideae: Trichosporeae
Mandirola Decne. Gesnerioideae: Gesnerieae
Metapetrocosmea W.T.Wang (synonym Deinostigma W.T.Wang & Z.Y.Li) Didymocarpoideae: Trichosporeae
Michaelmoelleria F.Wen, Y.G.Wei & T.V.Do Didymocarpoideae: Trichosporeae
Microchirita (C.B.Clarke) Yin Z.Wang Didymocarpoideae: Trichosporeae
Middletonia C.Puglisi Didymocarpoideae: Trichosporeae
Mitraria Cav. Gesnerioideae: Coronanthereae
Monophyllaea R.Br. Didymocarpoideae: Epithemateae
Monopyle Moritz ex Benth. & Hook.f. Gesnerioideae: Gesnerieae
Moussonia Regel Gesnerioideae: Gesnerieae
Napeanthus Gardner Gesnerioideae: Napeantheae
Nautilocalyx Linden ex Hanst. Gesnerioideae: Gesnerieae
Negria F.Muell. Gesnerioideae: Coronanthereae
Nematanthus Schrad. Gesnerioideae: Gesnerieae
Neomortonia Wiehler Gesnerioideae: Gesnerieae
Niphaea Lindl. Gesnerioideae: Gesnerieae
Nomopyle Roalson & Boggan Gesnerioideae: Gesnerieae
Oerstedina Wiehler Gesnerioideae: Gesnerieae
Orchadocarpa Ridl. Didymocarpoideae: Trichosporeae
Oreocharis Benth. Didymocarpoideae: Trichosporeae
Ornithoboea C.S.P.Parish ex C.B.Clarke Didymocarpoideae: Trichosporeae
Pachycaulos J.L.Clark & J.F.Sm. Gesnerioideae: Gesnerieae
Pagothyra (Leeuwenb.) J.F.Sm. & J.L.Clark Gesnerioideae: Gesnerieae
Paliavana Vell. ex Vand. Gesnerioideae: Gesnerieae
Paraboea (C.B.Clarke) Ridl. Didymocarpoideae: Trichosporeae
Paradrymonia Hanst. Gesnerioideae: Gesnerieae
Pearcea Regel Gesnerioideae: Gesnerieae
Petrocodon Hance Didymocarpoideae: Trichosporeae
Petrocosmea Oliv. Didymocarpoideae: Trichosporeae
Pheidonocarpa L.E.Skog Gesnerioideae: Gesnerieae
Phinaea Benth. Gesnerioideae: Gesnerieae
Platystemma Wall. Didymocarpoideae: Trichosporeae
Primulina Hance Didymocarpoideae: Trichosporeae
Pseudochirita W.T.Wang Didymocarpoideae: Trichosporeae
Rachunia D.J.Middleton & C.Puglisi Didymocarpoideae: Trichosporeae
Ramonda Rich.
(incl. Jankaea Boiss.)
Didymocarpoideae: Trichosporeae
Raphiocarpus Chun Didymocarpoideae: Trichosporeae
Reldia Wiehler Gesnerioideae: Beslerieae
Resia H.E.Moore Gesnerioideae: Beslerieae
Rhabdothamnopsis Hemsl. Didymocarpoideae: Trichosporeae
Rhabdothamnus A.Cunn. Gesnerioideae: Coronanthereae
Rhoogeton Leeuwenb. Gesnerioideae: Gesnerieae
Rhynchoglossum Blume Didymocarpoideae: Epithemateae
Rhynchotechum Blume Didymocarpoideae: Trichosporeae
Rhytidophyllum Mart. Gesnerioideae: Gesnerieae
Ridleyandra A.Weber & B.L.Burtt Didymocarpoideae: Trichosporeae
Rufodorsia Wiehler Gesnerioideae: Gesnerieae
Sanango G.S.Bunting & J.A.Duke Sanangoideae
Sarmienta Ruiz & Pav. Gesnerioideae: Coronanthereae
Seemannia Regel Gesnerioideae: Gesnerieae
Senyumia Kiew, A.Weber & B.L.Burtt Didymocarpoideae: Trichosporeae
Sepikea Schltr. Didymocarpoideae: Trichosporeae
Shuaria D.A.Neill & J.L.Clark Gesnerioideae: Beslerieae
Sinningia Nees Gesnerioideae: Gesnerieae
Smithiantha Kuntze Gesnerioideae: Gesnerieae
Solenophora Benth. Gesnerioideae: Gesnerieae
Somrania D.J.Middleton Didymocarpoideae: Trichosporeae
Spelaeanthus Kiew, A.Weber & B.L.Burtt Didymocarpoideae: Trichosporeae
Sphaerorrhiza Roalson & Boggan Gesnerioideae: Gesnerieae
Stauranthera Benth. Didymocarpoideae: Epithemateae
Streptocarpus Lindl.
(incl. Saintpaulia H.Wendl.)
Didymocarpoideae: Trichosporeae
Tetraphyllum Griff. ex C.B.Clarke
(syn. Tetraphylloides Doweld)
Didymocarpoideae: Trichosporeae
Titanotrichum Soler. Gesnerioideae: Titanotricheae
Tribounia D.J.Middleton Didymocarpoideae: Trichosporeae
Trichodrymonia Oerst. Gesnerioideae: Gesnerieae
Tylopsacas Leeuwenb. Gesnerioideae: Beslerieae
Vanhouttea Lem. Gesnerioideae: Gesnerieae
Whytockia W.W.Sm. Didymocarpoideae: Epithemateae

Ecology

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About half of the New World species (i.e. the subfamily Gesnerioideae) are co-adapted to bird pollination, particularly by hummingbirds in the Americas. Bird-pollinated species typically have two-lipped flowers in shades of red; examples are found in the genera Asteranthera, Columnea and Sinningia. Among Old World genera, Aeschynanthus has similar flowers.[17]

Cultivation

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Some genera in the family are grown as ornamental plants, both as garden plants and as houseplants. Such genera include: Aeschynanthus, Achimenes, Columnea, Gesneria, Haberlea, Nematanthus (syn. Hypocyrta), Ramonda, and Streptocarpus (Cape primroses, African violets).[17] One of the most familiar members of the family to gardeners are the African violets in Streptocarpus section Saintpaulia. Gesneriads are divided culturally into three groups on the basis of whether, and how, their stems are modified into storage organs: rhizomatous, tuberous, and "fibrous-rooted", meaning those that lack such storage structures (although all gesneriads have fibrous roots).[citation needed]

References

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  1. ^ a b "Gesneriaceae Rich. & Juss.". The International Plant Names Index. Retrieved 2021-04-13.
  2. ^ a b Wiersema, J.H.; Turland, N.J.; Barrie, F.R.; Greuter, W.; Hawksworth, D.L.; Herendeen, P.S.; Knapp, S.; Kusber, W.-H.; Li, D.-Z.; Marhold, K.; May, T.W.; McNeill, J.; Monro, A.M.; Prado, J.; Price, M.J. & Smith, G.F., eds. (2018) [continuously updated]. "Gesneriaceae". International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017: Appendices I–VII. Retrieved 2021-04-12.
  3. ^ "Gesneriaceae - plant family". Encyclopedia Britannica.
  4. ^ a b "Gesneriads". Encyclopedia of Life.
  5. ^ Christenhusz, M. J. M.; Byng, J. W. (2016). "The number of known plants species in the world and its annual increase". Phytotaxa. 261 (3): 201–217. doi:10.11646/phytotaxa.261.3.1.
  6. ^ Hyam, R. & Pankhurst, R. J. (1995). Plants and their names : a concise dictionary. Oxford: Oxford University Press. ISBN 978-0-19-866189-4. p. 209.
  7. ^ Dumortier, B.-C. (1829). Analyse des Familles de Plantes: avec l'indication des principaux genres qui s'y rattachent (in French). Tournay: J. Casterman. p. 30. OCLC 1116096010. Retrieved 2021-04-13.
  8. ^ "Columellia Ruiz & Pav.". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2021-04-13.
  9. ^ Angiosperm Phylogeny Group (2016). "An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG IV". Botanical Journal of the Linnean Society. 181 (1): 1–20. doi:10.1111/boj.12385.
  10. ^ "The Gesneriad Society". Retrieved 2021-04-11.
  11. ^ Weber, A.; Clark, J. L. & Möller, M. (2013). "A new formal classification of Gesneriaceae". Selbyana. 31 (2): 68–94. JSTOR 24894283.
  12. ^ a b c d e Weber, A.; Middleton, D. J.; Clark, J. L. & Möller, M. (2020). "Keys to the infrafamilial taxa and genera of Gesneriaceae". Rheedea. 30 (1): 5–47. doi:10.22244/rheedea.2020.30.01.02.
  13. ^ a b Ogutcen, Ezgi; Christe, Camille; Nishii, Kanae; Salamin, Nicolas; Möller, Michael & Perret, Mathieu (2021). "Phylogenomics of Gesneriaceae using targeted capture of nuclear genes". Molecular Phylogenetics and Evolution. 157: 107068. Bibcode:2021MolPE.15707068O. doi:10.1016/j.ympev.2021.107068. PMID 33422648.
  14. ^ "Peltanthera Benth.". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 9 August 2024.
  15. ^ "Rehmannia Libosch. ex Fisch. & C.A.Mey.". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2021-04-11.
  16. ^ "Gesneriaceae Dumort.". Plants of the World Online. Royal Botanic Gardens, Kew. Retrieved 2021-04-11.
  17. ^ a b Morley, B. (1978). "Gesneriaceae". In Heywood, V.H.; Moore, D.M.; Richardson, I.B.K. & Stearn, W.T. (eds.). Flowering Plants of the World. Oxford University Press. pp. 246–248. ISBN 978-0-19-217674-5.
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