Analyses of distribution, population dynamics, threats, and conservation strategies applied to endemic marine angiosperms from the Tropical Atlantic Ocean

Marine angiosperms form highly productive, complex and ecologically important ecosystems, so their conservation is essential. Unfortunately, various threats have been documented that are reducing the conservation status of natural populations. To know the current state of conservation of endemic marine angiosperms in the Tropical Atlantic Ocean, a bibliographic review has been carried out on the advances in knowledge made between 2006 and 2021 about their distribution, population dynamics, threats and in situ and ex situ conservation strategies. The most studied species in this time is Thalassia testudinum Banks & Sol. Ex K.D. Koenig and, in addition, it is the one that has the greatest number of in situ conservation strategies implemented. However, in general, the results on distribution, population dynamics and threats are limited for the rest of the species considered in this work. Regarding ex situ conservation, it is scarce for all the species studied and only two of them (T. testudinum and Syringodium filiforme Kütz) have material preserved in germplasm banks. Halophila baillonis Asch. Ex Dickie is the species to which the least conservation strategies have been applied, probably due to the fragmentation of its populations. Finally, in order to improve the conservation status of the seagrasses studied in the present work, it would be necessary to carry out in the future new studies on the taxonomy, distribution, seed physiology and in vitro culture.