The micrantha is a wild citrus from the papeda group, native to southern Philippines, particularly islands of Cebu and Bohol. Two varieties are recognized: small-flowered papeda, locally known as biasong, and small-fruited papeda or samuyao.
Description
The micrantha was first described to Western science in 1915 by Peter Jansen Wester, who worked for the Philippine Bureau of Agriculture at the time. ==Toxicity==
Toxicity
The micrantha contains a significant amount of bergapten, a linear furanocoumarin well known for its phototoxic effects. Of 61 Citrus varieties tested, C. micrantha had the highest concentration of bergapten of any Citrus species. In particular, C. micrantha contained almost twice as much bergapten as the bergamot orange whose essential oil is highly phototoxic. Indiscriminate use of bergamot essential oil has led to several cases of phytophotodermatitis, a potentially severe skin inflammation. In these cases, the primary causal agent is believed to be bergapten. ==Hybrids==
Hybrids
The Key lime (Citrus aurantifolia) is a hybrid of the micrantha and the citron. It, in turn, has been crossed with a lemon to produce the Persian lime (C. latifolia). There are lumias that are distinct micrantha/citron hybrids, such as the Pomme d'Adam, while other lumias, like the Borneo lemons, are micrantha/citron/pomelo tri-species hybrids. An Indonesian hybrid, the nansaran (C. × amblycarpa), is a C. hystrix/C. reticulata cross. ==References==