title: Fossil nutlets of Boraginaceae from the continental Eocene of Hamada of Méridja (southwestern Algeria): The first fossil of the Borage family in Africa.
abstract: OBJECTIVE
  The Paleogene deposits of the Hamada of Méridja, southwestern Algeria, are currently dated as lower-to-middle Eocene in age based on fossil gastropods and charophytes. Here we report the presence of fruits that can be assigned to the Boraginaceae s.str., apparently representing the first fossil record for this family in Africa, shedding new light on the historical biogeography of this group.
  
  
  METHODS
  Microscopic studies of the fossil nutlets were carried out and compared to extant Boraginaceae nutlets, and to types reported in the literature for this family.
  
  
  RESULTS
  The fossils are strikingly similar in general size and morphology, particularly in the finer details of the attachment scar and ornamentation, to nutlets of extant representatives of the Boraginaceae tribe Echiochileae, and especially the genus Ogastemma. We believe that these nutlets represent an extinct member of this lineage.
  
  
  CONCLUSIONS
  The Ogastemma-like fossils indicate that the Echiochileae, which are most diverse in northern Africa and southwestern Asia, have a long history in this region, dating back to the Eocene. This tribe corresponds to the basal-most clade in Boraginaceae s.str., and the fossils described here agree well with an assumed African origin of the family and the Boraginales I, providing an important additional calibration point for dating the phylogenies of this clade.
authors.affiliation: Laboratoire de Recherche Nr. 25, PRHPM-LECT, Département des Sciences de la Terre et de l'Univers, Université de Tlemcen, B.P. 119, Tlemcen 13000 Algeria sid.hammouda@gmail.com mweigend@uni-bonn.de.
authors.forename: Sid Ahmed
authors.initials: SA
authors.lastname: Hammouda
authors.affiliation: Nees-Institut für Biodiversität der Pflanzen, Meckenheimer Allee 170 53115 Bonn, Germany sid.hammouda@gmail.com mweigend@uni-bonn.de.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Weigend
authors.affiliation: Département des Sciences de la Terre et de l'Univers, Faculté des Sciences de la Nature et de la Vie, Université de Jijel, B.P. 98, Ouled Aissa, Jijel 18000 Algeria Laboratoire de Paléontologie, Stratigraphique et Paléoenvironnement, Faculté des Sciences de la Terre et de l'Univers, Université d'Oran 2, B.P. 1015, El Mnaouar, Oran 31000 Algeria.
authors.forename: Fateh
authors.initials: F
authors.lastname: Mebrouk
authors.affiliation: Nees-Institut für Biodiversität der Pflanzen, Meckenheimer Allee 170 53115 Bonn, Germany.
authors.forename: Juliana
authors.initials: J
authors.lastname: Chacón
authors.affiliation: Laboratoire de Recherche Nr. 25, PRHPM-LECT, Département des Sciences de la Terre et de l'Univers, Université de Tlemcen, B.P. 119, Tlemcen 13000 Algeria.
authors.forename: Mustapha
authors.initials: M
authors.lastname: Bensalah
authors.affiliation: Nees-Institut für Biodiversität der Pflanzen, Meckenheimer Allee 170 53115 Bonn, Germany.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Ensikat
authors.affiliation: Laboratoire de Recherche Nr. 25, PRHPM-LECT, Département des Sciences de la Terre et de l'Univers, Université de Tlemcen, B.P. 119, Tlemcen 13000 Algeria.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Adaci
mesh_terms: D000462:Algeria; D005075:Biological Evolution; D028082:Boraginaceae / Q000033:anatomy & histology / Q000145:classification*; D005580:Fossils / Q000033:anatomy & histology*; D005638:Fruit / Q000033:anatomy & histology / Q000145:classification
keywords: Boraginaceae s.str.; Codonaceae; Echiochileae; Eocene; Ogastemma; Wellstediaceae; fossils; northern Africa; nutlets; southwestern Asia