Open AccessDNA barcoding to analyse taxonomically complex groups in plants: the case of T hymus ( L amiaceae)
Author(s) -
Federici Silvia,
Galimberti Andrea,
Bartolucci Fabrizio,
Bruni Ilaria,
De mattia Fabrizio,
Cortis Pierluigi,
Labra Massimo
Publication year - 2013
Publication title -
botanical journal of the linnean society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.872
H-Index - 68
eISSN - 1095-8339
pISSN - 0024-4074
DOI - 10.1111/boj.12034
Subject(s) - biology , dna barcoding , intraspecific competition , taxon , taxonomy (biology) , evolutionary biology , intergenic region , species complex , interspecific competition , gene flow , genetic variation , botany , zoology , gene , genetics , phylogenetic tree , genome
We evaluated the utility of the core barcode regions ( matK and rbcL ) and the plastid intergenic spacer trnH ‐ psbA to distinguish between T hymus spp. This is a taxonomically complex group that has been investigated so far mainly using morphological approaches. Thirty‐six samples representing nine different morphospecies were collected and used for molecular analysis. The three markers showed clear amplification and sequencing. However, the genetic variation and the resulting haplotype networks showed that only T hymus capitatus forms a well‐defined ‘barcoding gap’ compared with the other taxa. The identification problems observed in the other T hymus spp. may be related to reduced gene flow among populations, resulting in high intraspecific and low interspecific genetic variation. This situation does not permit the definition of species‐specific barcodes. A second hypothesis suggests that morphological traits used for the delimitation of T hymus spp. do not reflect real biological and molecular species boundaries. If this is the case, the taxonomy of T hymus should be revised through extensive sampling and analyses with different tools (i.e. molecular variability, morphology, geographical distribution, etc.) to define the natural units at the species level. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society , 2013 , 171 , 687 – 699 .