A species peculiar to the Sertoens, where it grows on river borders. It is 50-60 feet tall, and the branches are so diffuse and double so much that they nearly reach the ground, forming a spacious cope. The fruit is an oblong drupe two or more inches long and half an inch thick, it always remains green even when ripe. The kernel is not hard like the kernels of the two preceding species, but ligneous and flexible and can easily be broken. It is covered with an astringent pulp. The seed has two oily cotyledons with a disagreeable taste, but abounding with an oil of which some use is now made. The common name is “Oiticica” or “Catingueira.”
Miers identified this species with Couepia uiti Benth. The range of that species extends north to Piauhy. Miers cannot be correct because C. uiti does not have the spreading habit or height of Arruda’s plant, and it has a round drupe with a thick hard endocarp. There is no doubt that P. umbrossisima is Licania rigida Benth., a species abundant in, and confined to, the dry regions of northeastern Brazil. L. rigida can grow to 60 ft tall, and has a very spreading habit. The drupe remains green when ripe and is of an elongate shape, furthermore the endocarp is thin and fibrous, not hard as in L. tomentosa. L. rigida also has much oil in the cotyledons. It is cultivated widely in Pernambuco, and the oil is extracted commercially. Brazil exported 16,606 metric tons of oil from this species in 1941 (see Bull. Imp. Inst. 44: 15. 1946). One of the uses of this oil is as a substitute for tongue oil in paint. The common name for L. rigida is still “Oiticica.” Conclusion.
The genus Pleragina is a mixture of species of Licania and Couepia. It is interesting to note that although few members of the Chrysobalanaceae grow in northeastern Brazil, three of them have fruit with local uses. There are comparatively few of the many Amazonian species with useful fruits. In summary the species of Pleragina are
Pleragina rufa Couepia rufa Arruda ex Ducke.
Pleragina odorata = Licania tomentosa Benth.
Pleragina umbrosissima — Licania rigida Benth.