The genus Casimiroa of the family Rutaceae was named in honor of Cardinal Casimiro Gomez de Ortega, a Spanish botanist of the 18th Century*.
It embraces 5 or 6 species of shrubs or trees. Of these, 3 shrubby species, C. pubescens Ramirez, C. pringlei Engl. and C. watsonii Engl., are apparently confined to Mexico and have received scant attention.
An additional species, C. emarginata Standl. & Steyerm., was described in 1944, based on a single specimen in Guatemala. It may be merely a form of C. sapota.

Of the 3 larger-growing forms, the best known is the common white sapote, called zapote blanco by Spanish-speaking people, abché or ahache by Guatemalan Indians, and Mexican apple in South Africa, and widely identified as C. edulis Llave & Lex.

The matasano (or matazano), C. sapota Oerst., is often not distinguished from C. edulis in the literature and the name matasano has been applied to other species in various localities.

The woolly-leaved white sapote, known to the Maya as yuy and set apart in Guatemala as matasano de mico, has been commonly considered a distinct species, C. tetrameria Millsp., but it may be only a variant of C. edulis.

White sapote trees range from 15 to 20 ft (4.5-6 m) up to 30 to 60 ft (9-18 m) in height. They have light-gray, thick, warty bark and often develop long, drooping branches.

The leaves, mostly evergreen are alternate, palmately compound, with 3 to 7 lanceolate leaflets, smooth or hairy on the underside.

The odorless flowers, small and greenish-yellow, are 4- or 5-parted, and borne in terminal and axillary panicles. They are hermaphrodite or occasionally unisexual because of aborted stigmas.

The fruit is round, oval or ovoid, symmetrical or irregular, more or less distinctly 5-lobed; 2 1/2 to 4 1/2 in (6.25-11.25 cm) wide and up to 4 3/4 in (12 cm) in length; with thin green, yellowish or golden skin coated with a very thin bloom, tender but inedible; and creamy-white or yellow flesh glinting with many tiny, conspicuous, yellow oil glands.

The flavor is sweet with a hint or more of bitterness and sometimes distinctly resinous. There may be 1 to 6 plump, oval, hard, white seeds, 1 to 2 in (2.5-5 cm) long and 1/2 to 1 in (1.25-2.5 cm) thick, but often some seeds are under-developed (aborted) and very thin. The kernels are bitter and narcotic.

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Properties of Zapote Blanco - White Sapote Favored by Aztecs

Calms the nervous system, cures insomnia, increases the amount of urine and perspiration, diminishes pain caused by rheumatism and lowers arterial pressure.

Aztec Method of Use.

Drink 1 cup before bed of the boiled mixture consisting of 10 to 20 leaves to 1/2 liter of water.
To Lower Arterial Pressure:
Drink 3 to 4 cups a day of the boiled mixture consisting of 15 Chayote leaves, 25 Zapote Blanco leaves, boil for 10 minutes in 1/2 liter of water, strain and sweeten to taste.

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