Plants in danger

Plants with complex floral morphologies are adapted to be pollinated by restricted pollinator assemblages and may suffer pollinator limitation. Understanding how floral traits and other variables relate to plant vulnerability can provide a powerful tool for predicting the conservation status and prioritizing the assessment of plants with scarce field data. Using circa 3000 records of rare and threatened (sensu IUCN) entomophilous plant taxa from seven Mediterranean countries, we evaluated how six floral traits and other eight intrinsic and extrinsic variables were related to plant vulnerability (less vs. more threatened plants). Besides, we analyzed 29 experts' opinions regarding the floral traits most related to floral complexity. Floral shape, reproductive unit, and flowering duration were good vulnerability indicators. Taxa with lip- and flag-shaped flowers were the most threatened, which agrees with the opinion of experts who considered lip- and flag-shaped flowers to have more complex morphologies. Also, plants with cylindrical inflorescences or solitary flowers were more threatened than those with flat-spherical inflorescences