did any foreign country rule or invade this island in historical times?
Yes, by the Portuguese.
Madagascar
European contact began in 1500, when the Portuguese sea captain Diogo Dias sighted the island, while participating in the 2nd Armada of the Portuguese India Armadas.

Matatana was the first Portuguese settlement on the south coast, 10 km west of Fort Dauphin. In 1508, settlers there built a tower, a small village, and a stone column. This settlement was established in 1613 at the behest of the viceroy of Portuguese India, Jeronimo de Azevedo.
One point where the armada language was later given the Spanish equivalent of the captain's name, Diego Suarez, which it held until it was renamed Antsiranana in 1975.

Contacts continued from the 1550s. Several colonization and conversion missions were ordered by King João III and by the Viceroy of India, including one in 1553 by Baltazar Lobo de Sousa. 
which of the following are only found naturally on madagascar More than 80 percent of Madagascar's 14,883 plant species are found nowhere else in the world, including five plant families. which continent is this island a part of? UNANSWERABLE what are the names of the plants endemic to this island? Plants of family "Didiereaceae", "Pachypodium" species along with orchids, and traveler's palm. how would you describe the first family of plant species mentioned in the list? Didiereaceae is a family of flowering plants found in continental Africa and Madagascar. and how would you describe the second family of plant species mentioned? It is a genus of succulent spine-bearing trees and shrubs, native to Madagascar and Africa. how is the climate in that island? It has a hot rainy season with frequent destructive cyclones and a cooler dry season.
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Madagascar [SEP] Portuguese
European contact began in 1500, when the Portuguese sea captain Diogo Dias sighted the island, while participating in the 2nd Armada of the Portuguese India Armadas. Matatana was the first Portuguese settlement on the south coast, 10 km west of Fort Dauphin. In 1508, settlers there built a tower, a small village, and a stone column. This settlement was established in 1613 at the behest of the viceroy of Portuguese India, Jeronimo de Azevedo. One point where the armada language was later given the Spanish equivalent of the captain's name, Diego Suarez, which it held until it was renamed Antsiranana in 1975.