Madagascar is in part of the biggest Gondwana in the past, so many milllions years ago.So doing research about plants fossils may refer that all countries belonging to Gondwana's continent at that time expected the same fossils!
Sure! Not only Madagascar, but even India was in Gondwana. Palaeobotanical evidence of similar flora was used in reconstruction of the positions of the continents in the past.
Note that Gondwana stretched across many latitudes so as natural regions are spread according to climate and such factors, so it was in the past. Places on the same continent may not have same flora if their latitudinal and thus climatic conditions are different.
The landmass might have similarities in the flora asDr.Umeji alluded to whcich add flora. Also a bit of relevance is the tectonic plates on which the existing land masses are. For example, in India while India has "stable" Gondwana, the land mass is moving ever slowly nothrward and with coastal changes, thus one sees terraces in the beaches of the Bay of Bengal , South India, especially corals beds have left uplifted Land Marks. Coastal Madagascar might give some of these clues.
You may find the following molecular paper by Barker & al. (2007) on Proteaceae, family that was distributed in the southern hemisphere and specifically in Madagascar.
Molecular dating of the 'Gondwanan' plant family Proteaceae is only partially congruent with the timing of the break-up of Gondwana.
Hi I'm doing Palaeobotany in Indian Lower Gondwana. There are potential workers in Birbal Sahani Institute of Palaeosciences dealing specifically Gondwana.