OXALIDACEAE

Oxalis dehradunensis

FAMILY OF THE WEEK : OXALIDACEAE
The OXALIDACEAE contains 3 genera and 875 species mostly in tropical and subtropical region.In India there are 2 genera and about 12 species distributed mostly in Himalayas. Indian sorrel is a common example found throughout India.
Vegetative characters :
Perennial herbs. Plants often produce fleshy rhizomes or bulbous tubers. The leaves are alternate or radical(Oxalis), digitately (Oxalis) or pinnately(Biophytum) compound and exstipulate.
The leaflets are folded and bent downwards in bud at night. The leaves of many species of Biophytum are sensitive and the leaflets bend down when touched.
Inflorescence and flowers :
The flowers are solitary or subumbellate or racemose.They are bracteate, complete and hermaphrodite, actinomorphic, pentamerous and hypogynous. The calyx is of five imbricate and persistent sepals which are free or united. The corolla is composed of five shortly clawed, free or basally connate petals. The androecium is of 10 stamens in alternate whorls.They are obdiplostemonous. The filaments are connate at the base. The gynoecium is pentacarpellary and syncarpous with a superior five-locular ovary. The styles are five, free and persistent and the stigmas are capitate or shortly divided.
Fruits and seeds :
The fruit is loculicidal capsule. The seeds have a straight embryo enveloped by a fleshy copious endosperm. An explosive aril is often present on the seeds.
Pollination and seed dispersal :
The flowers are protandrous and the pollination is by insects. The seeds are shot off as the capsule opens.
Examples :
Oxalis corniculata
Oxalis pes-caprae,
Oxalis corymbosa
Oxalis latifolia
Oxalis dehradunensis
Biophytum sensitivum