TAXONOMIC NOVELTIES IN THE VERBENA COMPLEX INFERRED FROM CPDNA AND NUCLEAR ETS/ITS SEQUENCES.

O'LEARY,NATALY; YUAN, YAOW; CHEMISQUY, AMELIA; OLMSTEAD, RICHARD

Tucumán, Argentina

Congreso; XXVII Meeting of the Willi Henning Society; 2008

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> The “Verbena complex” includes three genera, Verbena, Glandularia and Junellia, and is a rapidly diversifying group. Junellia is distinguished by its shrubby habit, woody rootstock and reduced, sometimes spiny, leaves, and a basic chromosome number x = 10; being Glandularia and Verbena leafy herbs or subshrubs, without woody rootstock nor spines. Verbena differs from Glandularia principally by its basic chromosome number being x=7 and x=5, respectively, as well as several morphological and anatomical characters. Junellia is a South American genus, distributed all along the arid andinian region, from Perú, Bolivia, Chile and Argentina. Verbena and Glandularia are distributed in temperate regions of both South America and North America. Junellia comprises 39 species, Verbena 44 species and Glandularia 84 species. For cladistic analyses 73-75 terminals, representing 19 Junellia taxa, 18 Verbena taxa, 22 to 33 Glandularia taxa, plus Urbania pappigera were sequenced, Lippia and Aloysia were used as outgroup taxa. Seven non-coding chloroplast regions were sequenced, these include intergenic spacers and/or introns in trnD-trnT, trnS-trnG, trnS-trnfM, trnT-trnL, trnG, trnL, and trnL-trnF, totaling ca. 5.3 kb (365 informative characters). The nuclear ITS and ETS were also sequenced (310 informative characters). Parsimony analyses were performed separately on the combined cpDNA dataset and on the nuclear ETS/ITS dataset. All phylogenetic analyses were conducted using TNT 1.1. This extensive sampling, together with previous studies, suggest that Junellia, as traditionally conceived, is paraphyletic and most ancestral among the three genera. Junellia should be restringed to the monophyletic group where Glandularia sect. Paraglandularia species and genus Urbania are nested. The rest of the species of Junellia integrate a monophyletic group that should be separated as a different genus: Thryothamnus. Verbena and Glandularia (excluding Glandularia sect. Paraglandularia, that is nested within Junellia) are monophyletic, but relationships within each genus are extremely difficult to resolve, nevertheless there is evidence that South and North American Verbena might be both monophyletic. Non-monophyly of Verbena and Glandularia recovered by cpDNA data is due to chloroplast transfer, as reported in previous studies. Verbena and Glandularia  are sister groups, and together they are sister to the newly classified Junellia. Thryothamnus is sister to the group comprising all the three genera Verbena + Glandularia + Junellia.