Résumé
A broad range of climatic and biogeographical conditions are represented
in the French Overseas Territories, from sub-polar to equatorial,
resulting in a high diversity of endemic species. We mobilized data from
herbaria, floras, checklists, literature, the expertise of botanists and
plant ecologists to compile the most complete dataset on endemic vascular
plants and bryophytes in the 15 French Overseas Territories. To date, 3748
spermatophytes (seed plants), 244 pteridophytes (ferns and lycophytes) and
448 bryophytes are strictly endemic to the overseas territories. New
Caledonia, French Polynesia and Réunion harbour the highest numbers of
strictly endemic species, yet French Guiana and the French Antilles
harbour high numbers of regional endemic species due to their proximity
with other territories. The endemic flora of these territories is highly
threatened. In particular, 51% of strictly endemic spermatophytes are
threatened and many species at risk belong to Rubiaceae and Orchidaceae
families. Around 82% and 69% of strict and regional endemic spermatophytes
and pteridophytes are found in the Paris herbaria. Only 34% of endemic
bryophytes have their label information fully databased so that their
total number in Paris herbaria is not known. Databasing the remaining
specimens in the collection will greatly enhance future research and
conservation projects. To facilitate the use of the information we
compiled, we provide a publicly searchable dataset of the checklist. This
study not only provides a picture of the flora of French overseas
territories; it also identifies gaps in knowledge on which future research
efforts in systematics, ecology and conservation could focus.