Citrofortunella are a large group of commercial hybrids that cross the

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

with other citrus. In the system of

citrus taxonomy Citrus taxonomy is 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. Cultiva ...

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 Peel (fruit), rind. It is said to resemble a 'huge, rough lemon'. It is one of the Citrus taxonomy#Citrons, original citrus fruits from which al ...

mandarin orange A mandarin orange (''Citrus reticulata''), often simply called mandarin, is a small, rounded citrus tree fruit. Treated as a distinct species of orange, it is usually eaten plain or in fruit salads. The mandarin is small and oblate, unlike the ...

pomelo The pomelo ( ; or pummelo, ''Citrus maxima''), also known as a shaddock, is the largest citrus fruit. It is an ancestor of several cultivated citrus species, including the bitter orange and the grapefruit. It is a natural, non-hybrid citrus fr ...

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 varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two dif ...

s, 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. 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 th ...

s. Of this group, the

calamansi Calamansi (''Citrus'' × ''microcarpa''), also known as calamondin, Philippine lime, or Philippine lemon, is a citrus hybrid cultivated predominantly in the Philippines. It is native to the Philippines, parts of Indonesia (Borneo, Sumatra, and ...

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 a citrus hybrid cultivated predominantly in the Philippines. It is native to the Philippines, parts of Indonesia (Borneo, Sumatra, and ...

(or Calamondin)– (

tangerine The tangerine is a type of citrus fruit that is orange in colour, that is considered either a variety of the mandarin orange (''Citrus reticulata''), or a closely related species, under the name ''Citrus tangerina'', or yet as a hybrid (''Citr ...

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), wi ...

crossed with kumquat) * Limequat – ''Citrofortunella floridana'' – (

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

crossed with kumquat) * Mandarinquat – varieties 'Nippon' and 'Indio' – ( satsuma mandarin crossed with kumquat) * Procimequat – ( limequat crossed with kumquat) * Sunquat – (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 language, Japanese or ; ) is a citrus fruit and plant in the family Rutaceae of China, Chinese origin. Yuzu has been cultivated mainly in East Asia, though it has also recently been grown in New Z ...

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