Citrofortunella are a large group of commercial hybrids that cross the

kumquat Kumquats (; zh, 金桔), or cumquats in Australian English, are a group of small fruit-bearing trees in the flowering plant family Rutaceae. Their taxonomy is disputed. They were previously classified as forming the now-historical genus ''For ...

with other citrus. In the system of

citrus taxonomy Citrus taxonomy refers to the botanical classification of the species, varieties, cultivars, and graft hybrids within the genus ''Citrus'' and related genera, found in cultivation and in the wild. Citrus taxonomy is complex and controversial. ...

established by Swingle, kumquats were placed in a different genus, '' Fortunella'', from ''Citrus'', which included

citron The citron (''Citrus medica''), historically cedrate, is a large fragrant citrus fruit with a thick rind. It is said to resemble a 'huge, rough lemon'. It is one of the original citrus fruits from which all other citrus types developed throu ...

mandarin orange The mandarin orange (''Citrus reticulata''), also known as the mandarin or mandarine, is a small citrus tree fruit. Treated as a distinct species of orange, it is usually eaten plain or in fruit salads. Tangerines are a group of orange-colou ...

pomelo The pomelo ( ), ''Citrus maxima'', is the largest citrus fruit from the family Rutaceae and the principal ancestor of the grapefruit. It is a natural, non-hybrid, citrus fruit, native to Southeast Asia. Similar in taste to a sweet grapefr ...

and papedas. The result of genetic crosses between kumquats and these other citrus would then be

intergeneric hybrid In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different breeds, varieties, species or genera through sexual reproduction. Hybrids are not always intermediates between their parents (such as in ...

s, so a novel genus name was coined for them in 1975, by

compound Compound may refer to: Architecture and built environments * Compound (enclosure), a cluster of buildings having a shared purpose, usually inside a fence or wall ** Compound (fortification), a version of the above fortified with defensive struc ...

ing the names of the contributing genera to form ''Citrofortunella''. That the genus is of a hybrid nature is represented by a multiplication sign before the genus name, for example × ''Citrofortunella microcarpa''. Recent phylogenetic work has shown kumquats to fall within ''Citrus'' rather than belonging to a distinct genus, meaning these would no longer be considered intergeneric hybrids, and use of ''Citrofortunella'' as a distinct genus name for these hybrids loses taxonomic validity. All would be placed instead within ''Citrus''. These hybrids combine some of the edibility properties of the more typical ''Citrus'' species with the cold hardiness of the kumquats, often being referred to as

cold hardy citrus Cold-hardy citrus is citrus with increased frost tolerance and which may be cultivated far beyond traditional citrus growing regions. Citrus species and citrus hybrids typically described as cold-hardy generally display an ability to withstand wint ...

. They produce small acidic fruit and are also more compact than other citrus, making them good

ornamental plant Ornamental plants or garden plants are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars that ...

s. Of this group, the

calamansi Calamansi (''Citrus'' × ''microcarpa''), also known as calamondin, Philippine lime, or Philippine lemon, is an economically important citrus hybrid predominantly cultivated in the Philippines. It is native to the Philippines, Borneo, Sumatra, ...

has a long history of propagation in Asia as an ornamental plant and food flavoring, but many members of the group are of relatively recent (20th century) generation. These have been given similar common names, portmanteaus that combine the '-quat' ending of kumquat with an indication of the other parent citrus. Some have been assigned separate species names, though there is no agreement on the validity of these names. They can also be represented as a cross between the parent species. The citrofortunella include: *

Calamansi Calamansi (''Citrus'' × ''microcarpa''), also known as calamondin, Philippine lime, or Philippine lemon, is an economically important citrus hybrid predominantly cultivated in the Philippines. It is native to the Philippines, Borneo, Sumatra, ...

(or Calamondin)– (

tangerine The tangerine is a type of citrus fruit that is orange in color. Its scientific name varies. It has been treated as a separate species under the name ''Citrus tangerina'' or ''Citrus'' × ''tangerina'', or treated as a variety of ''Citrus retic ...

crossed with kumquat) * Citrangequat – (

citrange The citrange (a portmanteau of ''citrus'' and ''orange'') is a citrus hybrid of the sweet orange and the trifoliate orange. The purpose of this cross was to attempt to create a cold hardy citrus tree (which is the nature of a trifoliate), with d ...

crossed with kumquat) *

Limequat The limequat is a citrofortunella hybrid that is the result of a cross between the Key lime and the kumquat, hybridized by Walter Tennyson Swingle in 1909. Description It is a small tree that grows into a contained bushy form. The leaves a ...

– ''Citrofortunella floridana'' – (

Key lime The Key lime or acid lime (''Citrus'' × ''aurantiifolia'' or ''C. aurantifolia'') is a citrus hybrid ('' C. hystrix'' × '' C. medica'') native to tropical Southeast Asia. It has a spherical fruit, in diameter. The Key lime is usually picked ...

crossed with kumquat) * Mandarinquat – varieties 'Nippon' and 'Indio' – ( satsuma mandarin crossed with kumquat) * Procimequat – (

limequat The limequat is a citrofortunella hybrid that is the result of a cross between the Key lime and the kumquat, hybridized by Walter Tennyson Swingle in 1909. Description It is a small tree that grows into a contained bushy form. The leaves a ...

crossed with kumquat) *

Sunquat A sunquat, also known as lemonquat or lemondrop, is a variety of citrus fruit, having an edible rind. It was initially created by Leslie Cude in Beeville, Texas, as a chance hybrid between a lemon The lemon (''Citrus limon'') is a spec ...

– (probably

Meyer lemon ''Citrus'' × ''meyeri'', the Meyer lemon (), is a hybrid citrus fruit native to China. It is a cross between a citron and a mandarin/pomelo hybrid. Mature trees are around tall with dark green shiny leaves. The flowers are white with a purp ...

crossed with kumquat) * Yuzuquat – (

yuzu Yuzu (''Citrus junos'', from Japanese or ) is a citrus fruit and plant in the family Rutaceae of East Asian origin. Yuzu has been cultivated mainly in East Asia, though recently also in New Zealand, Australia, Spain, Italy, and France. I ...

crossed with kumquat) * Jiangsu kumquat - previously classified as a distinct species of kumquat, but revealed by karyotyping to be a kumquat hybrid

References

{{citrus Asian cuisine Historically recognized angiosperm genera Citrus hybrids Fruits originating in Asia Garden plants of Asia Ornamental trees Kumquats