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 ''Fort ...

with other citrus. In the system of citrus taxonomy 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 (fruit), orange, it is usually eaten plain or in fruit salads. Tangerines are a group of ...

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 grapef ...

and papedas. The result of genetic crosses between kumquats and these other citrus would then be intergeneric hybrids, so a novel genus name was coined for them in 1975, by compounding 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 Validity or Valid may refer to: Science/mathematics/statistics: * Validity (logic), a property of a logical argument * Scientific: ** Internal validity, the validity of causal inferences within scientific studies, usually based on experiments ...

. 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. 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 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 (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 crossed with kumquat) * Limequat – ''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 The madarinquat, also misleadingly called orangequat, is any cross between a mandarin and a kumquat (Fortunella crassifolia). Mandarinquats are members of the citrofortunella group. The variety Nippon orangequat was first introduced in 1932 by D ...

– varieties 'Nippon' and 'Indio' – (

satsuma mandarin ''Citrus unshiu'' is a semi-seedless and easy-peeling citrus species, also known as miyagawa mandarin, unshu mikan, cold hardy mandarin, satsuma mandarin, satsuma orange, naartjie, and tangerine. ''Citrus unshiu'' was named after Unshu (Wenzho ...

crossed with kumquat) * Procimequat – ( limequat crossed with kumquat) * Sunquat – (probably Meyer lemon crossed with kumquat) *

Yuzuquat A ''yuzuquat'' is a trigeneric hybrid between a Yuzu lemon (''Citrus ichangensis'' x ''C. reticulata'') and 'Nagami' kumquat (''C. japonica'' 'Nagami'). It was developed by John Brown in Texas. The fruit often is used as a lemon substitute an ...

– ( yuzu 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