Biodiversity of ecosystems in an arid setting: The late Albian plant communities and associated biota from eastern Iberia

early Albian unit consisting of coal-bearing deposits [40] which sometimes also present amber [41]. Although more than 30 amber outcrops have been reported in the basin, the sites related to the desert system revealing the most diverse sets of bioinclusions and plant remains [29, 37, 42–44] are the successions of Arroyo de la Pascueta, San Just (both located in Teruel Province) and Cortes de Arenoso (Castello´n Province) (Fig 1). The present study is the first to provide a comprehensive treatment of the palaeobotanical and palynological content of the three afore- mentioned mid-Cretaceous sites. This paper aims to: (i) document the micro- and macrofloral assemblages together with the entomological content recovered from highly significant amber- bearing outcrops; (ii) reassess the age of the successions based on the presence of key biostrati- graphic markers; (iii) reconstruct the corresponding ecosystems with a special focus on the plant communities and insects which thrived on them; and (iv) compare the vegetation with coeval floras from presumably wetter settings. Material and methods Geological setting The study area is located in the Maestrazgo Basin, on the eastern part of a palaeogeographic domain referred to as the Iberian Basin Rift System (IBRS), Spain (Fig 1A). The sedimentary Fig 1. Location of the Maestrazgo Basin and its seven sub-basins (A) based on Aurell et al. [45]. The studied locations are indicated by coloured stars (San Just,

SJ; Arroyo de la Pascueta, AP; Cortes de Arenoso, CA). (B) Detail of the geological map with the location of San Just (SJ) section in the Las Parras Sub-basin. Based on data from the geological map of Spain Magna 1:50000 [46]. (C) Detail of the geological map showing the location of Arroyo de la Pascueta (AP) and Cortes de Arenoso (CA) sections. Based on data from the geological map of Spain Magna 1:50000 [47]. https://doi.org/10.1371/journal.pone.0282178.g001 PLOS ONE Late Albian desert biota from Iberia PLOS ONE | https://doi.org/10.1371/journal.pone.0282178 March 2, 2023 3 / 51