Citrus westeri Tanaka
Citrus micrantha is a species of wild citrus from the papeda group,
native to southern Philippines, particularly islands of
Bohol. Two varieties are recognized: small-flowered papeda
(C. micrantha var. micrantha), locally known as biasong, and
small-fruited papeda (C. micrantha var. microcarpa) or
Citrus micrantha is a progenitor species of lime. According to some
Citrus micrantha is likely a synonym of
2 See also
4 External links
Citrus micrantha was first described in 1915 by Peter Jansen Wester,
who worked for the Philippine Bureau of Agriculture at the time.
Wester collected ripe fruit specimens of biasong (small-flowered
Citrus micrantha var. micrantha) on islands of Cebu, Bohol,
Dumaguete, Negros, and in the Zamboanga and Misamis provinces in
Mindanao. The fruits were collected throughout the year, indicating
that the plant is ever-bearing. Biasong is characterized by small
flowers (thus the "small-flowered" moniker) with fewer stamens than
other papedas and oblong-obovate, few-loculed fruits. Inhabitants did
not use the fruits for food, but for hair-washing, and it had little
According to Wester's botanical description, biasong fruit aroma is
similar to that of the samuyao. The tree reaches 7.5 to 9 meters in
height. Leaves are 9–12 cm long, 2.7–4.0 cm wide,
broadly elliptical to ovate, crenate, thin, with base rounded or
broadly acute; apex acutely blunt pointed. Petioles are
3.5–6 cm long, broadly winged, up to 4 cm wide, with wings
(phyllodes) sometimes larger than the leaf. Flowers are small,
four-petaled, white with thin purple edge, 12–13 mm in
diameter, forming cymes of two to five. There are 15–17 equal
stamens. The ovary is obovoid, with 6–8 slender, distinct locules.
Fruits are obovate to oblong-obovate, 5–7 cm long, with
diameter of 3–4 cm, averaging 26 g in weight; their skin
is rather thick, lemon-yellow, fairly smooth or with transverse
corrugations; the pulp is juicy, grayish and acid, while juice cells
are short and blunt to long, long, slender and pointed, sometimes
containing a minute, greenish nucleus. They have numerous flat,
pointed, reticulate seeds.
Wester collected ripe samuyao (small-fruited papeda,
var. microcarpa) fruit specimens from cultivation in
June, and from November to February. Samuyao is rather smaller than
biasong, with tree attaining 4.5 meters. It has small, thin leaves and
flowers comparable in size to biasong. The fruit, 15–20 mm in
diameter, is likely to be the smallest in the whole genus. Wester
also recorded a somewhat more vigorous variety, called
"samuyao-sa-amoo" in Bohol, with slightly larger fruits; there is a
possibility that this species was actually Limonellus aurarius,
Georg Eberhard Rumphius
Georg Eberhard Rumphius back in 1741 in a nearby area,
although his description also fits a number of related species.
Wester gave the botanical description:
A shrubby tree, 4.5 meters tall, with slender branches and small, weak
spines; leaves 55 to 80 millimeters long, 20 to 25 millimeters broad,
ovate to ovate-oblong or elliptical, crenulate, thin, of distinct
fragrance, base rounded to broadly acute; apex obtuse, sometimes
notched, petioles 20 to 30 millimeters long, broadly winged, about 14
millimeters wide, wing area somewhat less than one-half of the leaf
blade; flowers in compact axillary or terminal cymes, 2 to 7, small, 5
to 9 millimeters in diameter, white, with trace of purple on the
outside; calyx small, not cupped, petals 3 to 5; stamens 15 to 18,
free, equal; ovary very small, globose to obovate; locules 7 to 9,
style distinct; stigma small, knob like; fruit 15 to 20 millimeters in
diameter, roundish in outline; base sometimes nippled; apex an
irregular, wrinkly cavity; surface corrugate, greenish lemon yellow;
oil cells usually sunken; skin very thin; pulp fairly juicy, acid,
bitter with distinct aroma; juice cells very minute, blunt, containing
a small, greenish nucleus; seeds small, flattened, sometimes beaked.
Clear, intensely fragrant oil can be produced from the samuyao peel,
with potential use in cosmetics, as evidenced by usage by local women
as a hair fragrance.
Citrus hystrix, related species of Southeast Asia
Citrus micrantha was first described and published in Philippine
Agricultural Review 1915, viii. 20."Plant Name Details for Citrus
micrantha". IPNI. Retrieved 2 September 2015.
Germplasm Resources Information Network (GRIN).
Agricultural Research Service
Agricultural Research Service (ARS), United States Department of
Agriculture (USDA). Retrieved 16 January 2018.
^ a b c d P. J. Wester (1915), "
Citrus Fruits In The Philippines",
Philippine Agricultural Review, 8
^ Jorma Koskinen, "Small-flowered and Small-fruited papeda", Citrus
^ Khan, Iqrar A.; Grosser, Jude W. (2004-05-01). "Regeneration and
characterization of somatic hybrid plants of
Citrus sinensis (sweet
Citrus micrantha, a progenitor species of lime".
Euphytica. Kluwer Academic Publishers. 137 (2): 271–278.
doi:10.1023/B:EUPH.0000041591.65333.3c. ISSN 1573-5060.
^ "TPL, treatment of
Citrus hystrix DC". The Plant List; Version 1.1.
(published on the internet).
Royal Botanic Gardens, Kew
Royal Botanic Gardens, Kew and the
Missouri Botanical Garden. 2013. Retrieved 2 September 2015.
^ a b c Swingle, Walter T. (1943). "The Botany of
Citrus and Its Wild
Citrus Industry, Vol 1 (rev). Berkeley: Univ of
California Press. Archived from the original on 2013-09-01.
Searching for the Elusive Samuyao, "Our Philippine Trees" blog
Looking for the Elusive Biyasong, "Our Philippine Trees" blog