Influence of Socio-Historical Events and Macroecological Patterns on the Endemic Plant Descriptions in the Iberian Peninsula

Since 1753 the description of vascular plants has been highly uneven. Given its high levels of plant endemism and long botanical history, the Iberian Peninsula is considered a suitable territory to study the species discovery process. Anova tests were conducted to explore the differences on the description dates for categories of range size and life-form. Correlation and GLM analyses were carried out to examine the spatial relationship between the number of described species and the plant richness and human influence variables. Two important peaks of description were identified: the first was associated to the extensive botanical exploration of the Baetic Mountains Hotspot by Boissier (mid-nineteenth century), and the second to the taxonomic revisions for Flora iberica (late 20th). As found in other studies, a negative correlation existed between the range size and the description date, while no differences were found for the life-form categories. The spatial pattern of the number of described species was highly correlated with the weighted endemism metric and to a lesser extent with the human influence. Changes in discovery effort have been governed by socio-historical factors and consequently the discovery curves are not reliable to indicate the final approach to completeness. However, the high number of recently discovered species suggests that the inventory is still incomplete.