The RUBIACEAE are a family of flowering plants , commonly known as
the COFFEE, MADDER, or BEDSTRAW FAMILY. It consists of terrestrial
trees, shrubs, lianas, or herbs that are recognizable by simple,
opposite leaves with interpetiolar stipules . The family contains
about 13,500 species in 611 genera , which makes it the fourth-largest
Rubiaceae has a cosmopolitan distribution ;
however, the largest species diversity is concentrated in the
(sub)tropics. Economic importance includes
Coffea , the source of
Cinchona , the source of the antimalarial alkaloid quinine ,
some dye plants (e.g.
Rubia ), and ornamental cultivars (e.g. Gardenia
* 1 Description
* 2 Distribution and habitat
* 3 Ecology
* 3.1 Flower biology
* 3.2 Fruit biology
* 3.3 Associations with other organisms
* 4 Systematics
* 4.1 Taxonomy
Subfamilies and tribes
* 4.2 Phylogeny
* 4.3 Evolution
* 5 Uses
* 5.1 Food
* 5.2 Beverage
* 5.3 Medicinal
* 5.4 Ornamentals
* 5.5 Dyes
* 6 Culture
* 7 Image gallery
* 8 References
* 9 External links
Rubiaceae are morphologically easily recognizable as a coherent
group by a combination of characters: opposite leaves that are simple
and entire, interpetiolar stipules, tubular sympetalous actinomorphic
corollas and an inferior ovary.
A wide variety of growth forms are present: shrubs are most common
Psychotria ), but members of the family can also be
Nauclea ), lianas (e.g.
), or herbs (e.g.
Spermacoce ). Some epiphytes are also
Myrmecodia ). The plants usually contain iridoids ,
various alkaloids , and raphide crystals are common. The leaves are
simple, undivided, and entire; leaf blades are usually elliptical,
with a cuneate base and an acute tip. In three genera (
Sericanthe ), bacterial leaf nodules can be observed as
dark spots or lines on the leaves. The phyllotaxis is usually
decussate, rarely whorled (e.g.
Fadogia ), or rarely alternate
resulting from the suppression of one leaf at each node (e.g. Sabicea
sthenula ). Characteristic for the
Rubiaceae is the presence of
stipules that are mostly fused to an interpetiolar structure on either
side of the stem between the opposite leaves. Their inside surface
often bears glands called "colleters", which produce mucilaginous
compounds protecting the young shoot. The "whorled" leaves of the
Rubieae tribe have classically been interpreted as true
leaves plus interpetiolar leaf-like stipules. The inflorescence is a
cyme , rarely of solitary flowers (e.g.
Rothmannia ), and is either
terminal or axillary and paired at the nodes. The flowers are usually
bisexual and usually epigynous. The perianth is usually biseriate ,
although the calyx is absent in some taxa (e.g.
Theligonum ). The
calyx has four or five sepals with basally fused lobes. The corolla is
sympetalous with four or five lobes, mostly actinomorphic, usually
tubular, mostly white or creamy but also yellow (e.g.
Mycelia basiflora ), and rarely blue (e.g.
Faramea calyptrata ) or red
Alberta magna ,
Ixora coccinea ). They have four or five stamens
, which are alternipetalous and epipetalous. Anthers are longitudinal
in dehiscence, but some genera are poricidal (e.g. Rustia ). The
gynoecium is syncarpous with an inferior ovary (rarely secondarily
Gaertnera , Pagamea ). Placentation is axial, rarely
Gardenia ); ovules are anatropous to hemitropous,
unitegmic, with a funicular obturator , one to many per carpel.
Nectaries are often present as a nectariferous disk atop the ovary.
The fruit is a berry , capsule (e.g.
Oldenlandia ), drupe (e.g.
Psychotria ), or schizocarp (e.g.
Cremocarpon ). Red fruits are fairly
Coffea arabica ); yellow (e.g. Rosenbergiodendron
formosum ), orange (e.g.
Vangueria infausta ), or blackish fruits
Pavetta gardeniifolia ) are equally common; blue fruits are
rather exceptional save in the
Psychotrieae and associated tribes.
Most fruits are about 1.0 cm in diameter; very small fruits are
relatively rare and occur in herbaceous tribes; very large fruits are
rare and confined to the
Gardenieae . The seeds are endospermous .
DISTRIBUTION AND HABITAT
Rubiaceae have a cosmopolitan distribution and are found in nearly
every region of the world, except for extreme environments such as the
polar regions and deserts. The distribution pattern of the family is
very similar to the global distribution of plant diversity overall.
However, the largest diversity is distinctly concentrated in the humid
tropics and subtropics. An exception is the
Rubieae tribe, which is
cosmopolitan but centered in temperate regions. Only a few genera are
Psychotria ), many are paleotropical, while
Afro-American distributions are rare (e.g.
Sabicea ). Endemic
rubiaceous genera are found in most tropical and subtropical floristic
regions of the world. The highest number of species is found in
Venezuela , and
New Guinea . When adjusted for area,
Venezuela is the most diverse, followed by
Rubiaceae consist of terrestrial and predominantly woody plants.
Woody rubiaceous shrubs constitute an important part of the
understorey of low- and mid-altitude rainforests.
tolerant of a broad array of environmental conditions (soil types,
altitudes, community structures, etc.) and do not specialize in one
specific habitat type (although genera within the family often
Rubiaceae are zoophilous . Entomophilous species produce nectar
from an epigynous disk at the base of the corolla tube to attract
Ornithophily is rare and is found in red-flowered species of
Bouvardia , and
Burchellia . Anemophylous species are found
in the tribes
Theligoneae and are characterized by
hermaphroditic and/or unisexual flowers that exhibit a set of
specialized features, such as striking sexual dimorphism, increased
receptive surface of the stigmas and pendulous anthers.
Rubiaceae species are hermaphroditic, outbreeding is
promoted through proterandry and spatial isolation of the reproductive
organs. More complex reproductive strategies include secondary pollen
presentation, heterodistyly, and unisexual flowers.
Secondary pollen presentation (also known as stylar pollen
presentation or ixoroid pollen mechanism) is especially known from the
Gardenieae and related tribes. The flowers are proterandrous and the
pollen is shed early onto the outside of the stigmas and/or the upper
part of the style, which serve as a 'receptaculum pollinis'. Increased
surface area and irregularity of the pollen receptacle, caused by
swellings, hairs, grooves or ridges often ensure a more efficient
pollen deposition. After elongation of the style, animals transport
the pollen to flowers in the female or receptive stage with exposed
stigmatic surfaces. A pollen catapult mechanism is present in the
genera Molopanthera and
Posoquerieae ) that projects
a spherical pollen mass onto visiting sphingidae .
Heterodistyly is another mechanism to avoid inbreeding and is widely
present in the
Rubiaceae family. The tribes containing the largest
number of heterostylous species are
Heterostyly is absent in groups that have secondary pollen
Unisexual flowers also occur in
Rubiaceae and most taxa that have
this characteristic are dioecious . The two flower morphs are however
difficult to observe as they are rather morphologically similar; male
flowers have a pistillode with the ovaries empty and female flowers
have empty, smaller anthers (staminodes). Flowers that are
morphologically hermaphrodite, but functionally dioecious are for
example found in
The dispersal units in
Rubiaceae can be entire fruits, syncarps,
mericarps, pyrenes or seeds. Fleshy fruit taxa are probably all
(endo)zoochorous (e.g. tribes
Psychotrieae ), while the
dispersal of dry fruits is often unspecialized (e.g. tribes
Spermacoceae ). When seeds function as diaspores , the dispersal is
either anemochorous or hydrochorous. The three types of wind-dispersed
Rubiaceae are dust seeds (rare, e.g.
Lerchea ), plumed
seeds (e.g. Hillia ), and winged seeds (e.g.
Coutarea ). Long-distance
dispersal by ocean currents is very rare (e.g. the seashore tree
Guettarda speciosa ). Other dispersal mechanisms are absent or at
least very rare. Some
Spermacoceae having seeds with elaiosomes are
probably myrmecochorous (e.g.
Spermacoce hepperiana ). Epizoochorous
taxa are limited to herbaceous
Galium aparine fruits
are densely covered with hooked bristly hairs).
ASSOCIATIONS WITH OTHER ORGANISMS
Myrmephytum , and
Squamellaria are succulent epiphytes that have evolved a mutualistic
relationship with ants. Their hypocotyl grows out into an
ant-inhabited tuber. Some shrubs or trees have ant holes in their
Globulostylis ). Some
Rubiaceae species have domatia that
are inhabited by mites (viz. acarodomatia ; e.g. Plectroniella armata
An intimate association between bacteria and plants is found in three
rubiaceous genera (viz.
Psychotria , and
Sericanthe ). The
presence of endophytic bacteria is visible by eye because of the
formation of dark spots or nodules in the leaf blades. The endophytes
have been identified as
Burkholderia bacteria. A second type of
bacterial leaf symbiosis is found in the genera
Vangueria (all belonging to the
Vanguerieae tribe), where
Burkholderia bacteria are found freely
distributed among the mesophyll cells and no leaf nodules are formed.
The hypothesis regarding the function of the symbiosis is that the
endophytes provide chemical protection against herbivory by producing
certain toxic secondary metabolites.
Rubiaceae family is named after
Rubia , a name used by Pliny the
Elder in his Naturalis Historia for madder (
Rubia tinctorum ). The
roots of this plant have been used since ancient times to extract
alizarin and purpurin, two red dyes used for coloring clothes. The
name rubia is therefore derived from the Latin word ruber, meaning
red. The well-known genus
Rubus (blackberries and raspberries) is
unrelated and belongs to
Rosaceae , the rose family.
Rubiaceae (nomen conservandum ) was published in 1789 by
Antoine Laurent de Jussieu , but the name was already mentioned in
Several historically accepted families are since long included in
Rubiaceae: Aparinaceae, Asperulaceae, Catesbaeaceae, Cephalanthaceae,
Cinchonaceae, Coffeaceae, Coutariaceae, Galiaceae, Gardeniaceae,
Guettardaceae, Hameliaceae, Hedyotidaceae, Houstoniaceae,
Hydrophylacaceae, Lippayaceae, Lygodisodeaceae, Naucleaceae,
Nonateliaceae, Operculariaceae, Pagamaeaceae, Psychotriaceae,
Randiaceae, Sabiceaceae, Spermacoceaceae.
More recently, the morphologically quite different families
Dialypetalanthaceae, Henriqueziaceae, and Theligonaceae were
reduced to synonymy of Rubiaceae.
Subfamilies And Tribes
The classical classification system of
Rubiaceae distinguished only
two subfamilies: Cinchonoideae, characterized by more than one ovule
in each locule, and Coffeoideae, having one ovule in each locule.
This distinction, however, was criticized because of the distant
position of two obviously related tribes, viz.
Gardenieae with many
Ixoreae with one ovule in Coffeoideae, and
because in species of
Tarenna the number of ovules varies from one to
several in each locule. During the twentieth century other
characters were used to delineate subfamilies, e.g. stylar pollen
presentation, raphides , endosperm , heterostyly , etc. On this basis,
three or eight subfamilies were recognised. The last subfamilial
classification solely based on morphological characters divided
Rubiaceae into four subfamilies: Cinchonoideae, Ixoroideae,
Antirheoideae, and Rubioideae. In general, problems of subfamilies
Rubiaceae based on morphological characters are linked
with the extreme naturalness of the family, hence a relatively low
divergence of its members.
The introduction of molecular phylogenetics in
Rubiaceae research has
corroborated or rejected several of the conclusions made in the
pre-molecular era. There is support for the subfamilies Cinchonoideae,
Ixoroideae, and Rubioideae, although differently circumscribed, and
Antirheoideae is shown to be polyphyletic . The tribe Coptosapelteae
including the genera
Coptosapelta , and the monogeneric
Luculieae have not been placed within a subfamily and are sister
to the rest of Rubiaceae. Currently, in most molecular research
Rubiaceae family, the classification with three
subfamilies (Cinchonoideae, Ixoroideae, and Rubioideae) is followed.
However, an alternative view is proposed where only two subfamilies
are recognized, an expanded
Cinchonoideae (that includes Ixoroideae,
Coptosapeltaeae and Luculieae) and Rubioideae. The adoption of the
Melbourne Code for botanical nomenclature had an unexpected impact on
many names that have been long in use and are well-established in
literature. According to the Melbourne Code, the subfamilial name
Ixoroideae should be replaced by Dialypetalanthoideae. However,
Dialypetalanthus is morphologically quite aberrant in
Rubiaceae and if
it should be excluded from Rubiaceae, the subfamilial name remains
Ixoroideae. Molecular studies also have substantial impact on tribal
delimitations and taxonomic changes are still being made. Also here,
according to the Melbourne Code, the tribe
Condamineeae should be
renamed to Dialypetalantheae. The following list contains the validly
published tribe names, however, some tribes might be disputed. The
approximate number of species is indicated between brackets, however,
several genera and species are not yet placed in a tribe.
* BASAL RUBIACEAE (59 sp.)
Coptosapelteae Bremek. ex S.P.Darwin (55 sp.)
Luculieae Rydin & B.Bremer (4 sp.)
* CINCHONOIDEAE Raf. (1708 sp.)
Chiococceae Benth. & Hook.f. (224 sp.)
Cinchoneae DC. (125 sp.)
Guettardeae DC. (747 sp.)
Hamelieae A.Rich. ex DC. (171 sp.)
Hymenodictyeae Razafim. & B.Bremer (25 sp.)
Hillieae Bremek. ex S.P.Darwin (29 sp.)
Isertieae A.Rich. ex DC. (16 sp.)
Naucleeae DC. ex Miq. (192 sp.)
Rondeletieae DC. ex Miq. (178 sp.)
Strumpfieae Delprete & T.J.Motley (1 sp.)
* IXOROIDEAE Raf. (3960 sp.)
Airospermeae Kainul. & B.Bremer (7 sp.)
Alberteae Hook.f. (7 sp.)
Aleisanthieae Mouly, J.Florence & B.Bremer (10 sp.)
Augusteae Kainul. & B.Bremer (86 sp.)
Bertiereae Bridson (57 sp.)
Coffeeae DC. (303 sp.)
Condamineeae Hook.f. (305 sp.)
Cordiereae A.Rich. ex DC. emend. Mouly (124 sp.)
Cremasporeae Bremek. ex S.P.Darwin (2 sp.)
Crossopterygeae F.White ex Bridson (1 sp.)
Gardenieae A.Rich. ex DC. (587 sp.)
Greeneeae Mouly, J.Florence & B.Bremer (9 sp.)
Henriquezieae Benth. & Hook.f. (20 sp.)
Ixoreae Benth. & Hook.f. (545 sp.)
Jackieae Korth. (1 sp.)
Mussaendeae Hook.f. (221 sp.)
Octotropideae Bedd. (96 sp.)
Pavetteae A.Rich. ex Dumort. (624 sp.)
Posoquerieae Delprete (23 sp.)
Retiniphylleae Hook.f. (20 sp.)
Sabiceeae Bremek. (164 sp.)
Scyphiphoreae Kainul. & B.Bremer (1 sp.)
Sherbournieae Mouly & B.Bremer (54 sp.)
Sipaneeae Bremek. (43 sp.)
Steenisieae Kainul. & B.Bremer (5 sp.)
Trailliaedoxeae Kainul. & B.Bremer (1 sp.)
Vanguerieae A.Rich. ex Dumort. (644 sp.)
* RUBIOIDEAE Verdc. (7571 sp.)
Anthospermeae Cham. & Schltdl. ex DC. (208 sp.)
Argostemmateae Bremek. ex Verdc. (215 sp.)
* Clarkelleae Deb (1 sp.)
Colletoecemateae Rydin & B.Bremer (3 sp.)
Coussareeae Hook.f. (402 sp.)
Craterispermeae Verdc. (16 sp.)
Cyanoneuroneae Razafim. & B.Bremer (5 sp.)
Danaideae B.Bremer & Manen (50 sp.)
Dunnieae Rydin & B.Bremer (1 sp.)
Gaertnereae Bremek. ex S.P.Darwin (95 sp.)
Knoxieae Hook.f. (131 sp.)
Lasiantheae B.Bremer & Manen (239 sp.)
Mitchelleae Razafim. & B.Bremer & Manen (14 sp.)
Morindeae Miq. (165 sp.)
Ophiorrhizeae Bremek. ex Verdc. (364 sp.)
Paederieae DC. (81 sp.)
Palicoureeae Robbr. & Manen (817 sp.)
Perameae Bremek. ex S.P.Darwin (14 sp.)
Prismatomerideae Y.Z.Ruan (23 sp.)
Psychotrieae Cham. & Schltdl. (2114 sp.)
Putorieae (34 sp.)
Rubieae Baill. (938 sp.)
Schizocoleeae Rydin & B.Bremer (2 sp.)
Schradereae Bremek. (55 sp.)
Spermacoceae Cham. padding:0;">
The fossil history of the
Rubiaceae goes back at least as far as the
Eocene . The geographic distribution of these fossils, coupled with
the fact that they represent all three subfamilies, is indicative of
an earlier origin for the family, probably in the
Late Cretaceous or
Paleocene . Although fossils dating back to the
Palaeocene have been referred to the family by various authors, none
of these fossils has been confirmed as belonging to the Rubiaceae.
The oldest confirmed fossils, which are fruits that strongly resemble
those of the genus
Emmenopterys , were found in the Washington and are
48–49 million years old. A fossil infructescence and fruit found in
44 million-year-old strata in
Oregon was assigned to Emmenopterys
dilcheri, an extinct species. The next-oldest fossils date to the Late
Eocene and include
Faramea from Panama,
New Caledonia , and Paleorubiaceophyllum, an extinct
genus from the southeastern
United States .
Rubiaceae are known from three regions in the
America north of Mexico, Mexico-Central America-Caribbean, and
Southeast Pacific-Asia). In the
Oligocene , they are found in these
three regions plus Africa. In the
Miocene , they are found in these
four regions plus South America and Europe.
Staple foods are not found in the Rubiaceae; instead, some species
are consumed locally and fruits may be used as famine food . Examples
are African medlar fruits (e.g. V. infausta , V. madagascariensis ),
African peach (
Nauclea latifolia ), and noni (
Morinda citrifolia ).
The most economically important member of the family and the world's
second-most important commodity (after petroleum) is the genus Coffea
used in the production of coffee .
Coffea includes 124 species, but
only three species are cultivated for coffee production: C. arabica ,
C. canephora , and C. liberica .
The bark of trees in the genus
Cinchona is the source of a variety of
alkaloids , the most familiar of which is quinine , one of the first
agents effective in treating malaria . Woodruff (
Galium odoratum ) is
a small herbaceous perennial that contains coumarin , a natural
precursor of warfarin , and the South American plant Carapichea
ipecacuanha is the source of the emetic ipecac .
Psychotria viridis is
frequently used as a source of dimethyltryptamine in the preparation
of ayahuasca , a psychoactive decoction. The bark of the species
Breonadia salicina have been used in traditional African medicine for
many years. The leaves of the Kratom plant (
Mitragyna speciosa )
contain a variety of alkaloids, including several psychoactive
alkaloids and is traditionally prepared and consumed in Southeast
Asia, where it has been known to exhibit both painkilling and
stimulant qualities, behaving as a μ-opioid receptor agonist , and
often being used in traditional Thai medicine in a similar way to and
often as a replacement for opioid painkillers like morphine .
Originally from China, the common gardenia (
Gardenia jasminoides ) is
a widely grown garden plant and flower in frost-free climates
worldwide. Several other species from the genus are also seen in
horticulture. The genus
Ixora contains plants cultivated in
warmer-climate gardens; the most commonly grown species, Ixora
coccinea , is frequently used for pretty red-flowering hedges.
Mussaenda cultivars with enlarged, colored calyx lobes are shrubs with
the aspect of
Hydrangea ; they are mainly cultivated in tropical Asia.
The New Zealand native
Coprosma repens is a commonly used plant for
hedges . The South African
Rothmannia globosa is seen as a specimen
tree in horticulture.
Nertera granadensis is a well-known house plant
cultivated for its conspicuous orange berries. Other ornamental plants
Pentas , and
Rose madder , the crushed root of
Rubia tinctorum , yields a red dye,
and the tropical
Morinda citrifolia yields a yellow dye.
Warszewiczia coccinea is the national flower of Trinidad and
Coffea arabica is the national flower of
Cinchona is the national tree of
* The International
Coffee Day is held each year on September 29.
* ^ A B "Angiosperm Phylogeny Website". Retrieved 1 June 2014.
* ^ Igersheim A, Puff C, Leins P, Erbar C (1994). "Gynoecial
Gaertnera Lam. and of presumably allied taxa of the
Psychotrieae (Rubiaceae): secondary 'superior' vs. inferior ovaries".
Botanische Jahrbücher fur Systematik. 116: 401–414.
* ^ A B C D E Robbrecht E (1988). "Tropical woody Rubiaceae". Opera
Botanica Belgica. 1: 1–271.
* ^ Takhtajan A (2009). Flowering Plants (2 ed.). Springer. ISBN
* ^ A B C Davis AP, Govaerts R, Bridson DM, Ruhsam M, Moat J,
Brummitt NA (2009). "A global assessment of distribution, diversity,
endemism, and taxonomic effort in the Rubiaceae". Annals of the
Missouri Botanical Garden. 96 (1): 68–78. doi :10.3417/2006205 .
* ^ Delprete PG (2009). "Taxonomic history, morphology, and
reproductive biology of the tribe
Ixoroideae)". Annals of the Missouri Botanical Garden. 96 (1):
79–89. doi :10.3417/2006192 .
* ^ Anderson WR (1973). "A morphological hypothesis for the origin
of heterostyly in the Rubiaceae". Taxon. 22 (5/6): 537–542. doi
* ^ Bridson DM (1987). "Studies in African Rubiaceae-Vanguerieae: a
new circumscription of
Pyrostria and a new subgenus,
Bullockia". Kew Bulletin. 42: 611–639. doi :10.2307/4110068 .
* ^ Kapitany A (2007). Australian succulent plants: an
introduction. Boronia, Victoria: Kapitany Concepts. pp. 144–155.
ISBN 0-646-46381-0 .
* ^ Verstraete B, Lachenaud O, Smets E, Dessein S, Sonké B (2013).
"Taxonomy and phylogeny of Cuviera (Rubiaceae-Vanguerieae) and
reinstatement of the genus
Globulostylis with the description of three
new species". Botanical Journal of the Linnean Society. 173 (3):
407–441. doi :10.1111/boj.12062 .
* ^ Tilney PM, van Wyk AE, van deer Merwe CF (2012). "Structural
evidence in Plectroniella armada (Rubiaeae) for possible material
exchange between domatia and mites" . PLoS ONE. 7 (7): e39984. PMC
3390328 . PMID 22792206 . doi :10.1371/journal.pone.0039984 .
* ^ Lemaire B, Vandamme P, Merckx V, Smets E, Dessein S (2011).
"Bacterial leaf symbiosis in angiosperms: host specificity without
co-speciation" . PLoS ONE. 6 (9): e24430. PMC 3168474 . PMID
21915326 . doi :10.1371/journal.pone.0024430 .
* ^ Verstraete B, Van Elst D, Steyn H, Van Wyk B, Lemaire B, Smets
E, Dessein S (2011). "Endophytic bacteria in toxic South African
plants: identification, phylogeny and possible involvement in
gousiekte" . PLoS ONE. 6 (4): e19265. PMC 3082559 . PMID 21541284 .
doi :10.1371/journal.pone.0019265 .
* ^ Verstraete B, Janssens S, Smets E, Dessein S (2013). "Symbiotic
beta-proteobacteria beyond legumes:
Burkholderia in Rubiaceae" . PLoS
ONE. 8 (1): e55260. PMC 3555867 . PMID 23372845 . doi
* ^ Verstraete B, Janssens S, Lemaire B, Smets E, Dessein S (2013).
"Phylogenetic lineages in
Vanguerieae (Rubiaceae) associated with
Burkholderia bacteria in sub-Saharan Africa". American Journal of
Botany. 100: 2380–2387. PMID 24275705 . doi :10.3732/ajb.1300303 .
* ^ Sieber S, Carlier AL, Neuburger M, Grabenweger G, Eberl L,
Gademann K (2015). "Isolation and total synthesis of kirkamide, an
aminocyclitol from an obligate leaf nodule symbiont". Angewandte
Chemie - International Edition. 54: 7968–7970. doi
:10.1002/anie.201502696 . CS1 maint: Multiple names: authors list
* ^ Simpson MG (2006).
Plant Systematics (1 ed.). Elsevier Academic
Press. ISBN 978-0-12-644460-5 .
* ^ Jussieu A L de (1789).
Genera Plantarum. Paris: Herissant &
Barrois. p. 206.
* ^ Durand JF (1782). Notions Élémentaires de Botanique. Dijon:
LN Frantin. p. 274.
* ^ Fay MF, Bremer B, Prance GT, van der Bank M, Bridson D, Chase
MW (2000). "Plastid rbcL sequence data show
Dialypetalanthus to be a
member of Rubiaceae". Kew Bulletin. 55 (4): 853–864. doi
* ^ Rogers GK (1981). "The wood of Gleasonia, Henriquezia, and
Platycarpum (Rubiaceae) and its bearing on their classification: some
new considerations". Brittonia. 33 (3): 461–465. doi
* ^ Wunderlich R (1971). "Die systematische Stellung von
Theligonum". Österreichische botanische Zeitschrift. 119: 329–394.
doi :10.1007/bf01377490 .
* ^ Rutishauser F, Ronse Decraene LP, Smets E, Mendoza-Heuer I
Theligonum cynocrambe: developmental morphology of a peculiar
Plant Systematics and Evolution. 210 (1): 1–24.
doi :10.1007/BF00984724 .
* ^ A B Robbrecht E, Manen JF (2006). "The major evolutionary
lineages of the coffee family (Rubiaceae, angiosperms). Combined
analysis (nDNA and cpDNA) to infer the position of
Luculia, and supertree construction based on rbcL, rps16, trnL-trnF
and atpB-rbcL data. A new classification in two subfamilies,
Cinchonoideae and Rubioideae". Systematic Geography of Plants. 76:
* ^ Hooker JD (1873). "Ordo LXXXIV. Rubiaceae". In Bentham G,
Genera planetarium ad exemplaria imprimis in herbaria
kewensibus servata defirmata. 2. London. pp. 7–151.
* ^ Schumann K (1891). "Rubiaceae". In Engler A, Prantl K. Die
natürlichen Pflanzenfamilien. 4. Leipzig: Engelmann. pp. 1–156.
* ^ Baillon H (1878). "Sur les limits du genre Ixora". Adansonia.
* ^ Solereder H (1893). "Ein Beitrag zur anatomischen
Charakteristik und zur Systematik deer Rubiaceen". Bull. Herb.
Boissier. 1: 167–183.
* ^ Verdcourt B (1958). "Remarks on the classification of the
Rubiaceae". Bulletin du Jardin botanique de l'état, Bruxelles. 28:
209–281. doi :10.2307/3667090 .
* ^ Bremekamp CEB (1966). "Remarks on the position, the
delimitation and the subdivision of the Rubiaceae". Acta Botanica
Neerlandica. 15: 1–33. doi :10.1111/j.1438-8677.1966.tb00207.x .
* ^ Bremer B, Andreasen K, Olsson D (1995). "Subfamilial and tribal
relationships in the
Rubiaceae based on rbcL sequence data". Annals of
the Missouri Botanical Garden. 82: 383–397. doi :10.2307/2399889 .
* ^ Rydin C, Kainulainen K, Razafimandimbison SG, Smedmark JE,
Bremer B (2009). "Deep divergences in the coffee family and the
systematic position of Acranthera".
Plant Systematics and Evolution.
278: 101–123. doi :10.1007/s00606-008-0138-4 .
* ^ Bremer B (2009). "A review of molecular phylogenetic studies of
Rubiaceae". Annals of the Missouri Botanical Garden. 96 (1): 4–26.
doi :10.3417/2006197 .
* ^ Reveal JL (2012). "Newly required infrafamilial names mandated
by changes in the code of nomenclature for algae, fungi and plants".
Phytoneuron. 33: 1–32.
* ^ Kainulainen K, Razafimandimbison SG, Bremer B (2013).
"Phylogenetic relationships and new tribal delimitations in subfamily
Ixoroideae (Rubiaceae)". Botanical Journal of the Linnean Society. 173
(3): 387–406. doi :10.1111/boj.12038 .
* ^ Mouly A, Kainulainen K, Persson C, Davis AP, Wong KM,
Razafimandimbison SG, Bremer B (2014). "Phylogenetic structure and
clade circumscriptions in the
Gardenieae complex (Rubiaceae)". Taxon.