title: Contrasted Genetic Diversity, Relevance of Climate and Host Plants, and Comments on the Taxonomic Problems of the Genus Picoa (Pyronemataceae, Pezizales).
abstract: The species concept within the genus Picoa Vittad. is here revisited in light of new molecular and ecological data obtained from samples collected throughout the Mediterranean basin. Two highly diverse widespread clades and four additional minor lineages were significantly supported by three genes dataset (ITS, 28s LSU and RPB2) inferences for 70 specimens. The two widespread clades occur in very different geographical and ecological areas associated with exclusive host plants in the genus Helianthemum. SEM study of spore surface morphology in these lineages revealed the existence of smooth ascospores in the majority of these clades. However the most frequent lineage in Europe and coastal North Africa displayed either smooth or verrucose spores. Hence this morphological criterion cannot be reliably used to discriminate between the different clades. In addition, SEM observations made on ascospores from several original collections of P. juniperi and P. lefebvrei supported the hypothesis that ornamentation depends on the degree of maturity in some of these lineages. Geographical and ecological, rather than morphological data are here suggested as the most useful characters to separate the different lineages in Picoa. Further studies focusing on these features are needed before the names P. juniperi and P. lefebvrei can be unambiguously linked with the genetic lineages observed.
authors.affiliation: Laboratoire de Biologie des Microorganismes et de Biotechnologie, Département de Biotechnologie, Faculté des Sciences de la nature et de la vie, Université d'Oran 1, Ahmed Ben Bella, Algérie.
authors.forename: Fatima El-Houaria
authors.initials: Fel-H
authors.lastname: Zitouni-Haouar
authors.affiliation: Departamento Ciencias de la Vida, Universidad de Alcalá, 28871, Alcalá de Henares, Madrid, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Alvarado
authors.affiliation: Laboratoire d'Ecologie Pastorale, Institut des Régions Arides, 4119, Médenine. Tunisia; Laboratoire Microorganismes and Biomolécules Actives, Université Tunis El Manar & Université de Carthage, Campus Universitaire, 2092, Tunis, Tunisia.
authors.forename: Imed
authors.initials: I
authors.lastname: Sbissi
authors.affiliation: Laboratoire Microorganismes and Biomolécules Actives, Université Tunis El Manar & Université de Carthage, Campus Universitaire, 2092, Tunis, Tunisia.
authors.forename: Abdellatif
authors.initials: A
authors.lastname: Boudabous
authors.affiliation: Laboratoire de Biologie des Microorganismes et de Biotechnologie, Département de Biotechnologie, Faculté des Sciences de la nature et de la vie, Université d'Oran 1, Ahmed Ben Bella, Algérie.
authors.forename: Zohra
authors.initials: Z
authors.lastname: Fortas
authors.affiliation: Departamento Ciencias de la Vida, Universidad de Alcalá, 28871, Alcalá de Henares, Madrid, Spain.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Moreno
authors.affiliation: Departamento Ciencias de la Vida, Universidad de Alcalá, 28871, Alcalá de Henares, Madrid, Spain.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Manjón
authors.affiliation: Laboratoire Microorganismes and Biomolécules Actives, Université Tunis El Manar & Université de Carthage, Campus Universitaire, 2092, Tunis, Tunisia.
authors.forename: Maher
authors.initials: M
authors.lastname: Gtari
mesh_terms: D001203:Ascomycota / Q000145:classification / Q000235:genetics* / Q000648:ultrastructure; D002980:Climate; D014644:Genetic Variation; D019684:Magnoliopsida / Q000382:microbiology*; D019083:Mediterranean Region; D010802:Phylogeny