Phylogeny of Lamiales, with emphasis on Gratiolaceae species to Brazil / Filogenia molecular de Lamiales, com ênfase em espécies nativas de Gratiolaceae




The history of Scrophulariaceae has been characterized by different treatments regarding the circumscription of the family. Some proposals have included in the family groups currently recognized as belonging to families such as Globulariaceae, Lentibulariaceae, Orobanchaceae, Plantaginaceae e Selaginaceae. Tribe Gratioleae, traditionally included in Scrophulariaceae, inrecent yearshas been assumed as a member of Plantaginaceae. However, a recent study raised this tribe to family status (Gratiolaceae). Affinity relationships among Gratiolaceae genera have so far been established on bases of morphological characters. The aim of the present work was to establish affinity relationships inside the family on bases of molecular phylogeny criteria and to test the monophyly of the constituent G ratilaceae genera. Sequences of mitochondrial NAD and plastid rbcL and trnL-trnL-F were obtained. Phylogenetic inferences were obtained based on DNA sequences and maximum parsimony and bayesian analysis. The congruence of topologies based on individual DNA regions were evaluated by means of the ILD test. The results obtained give support to previous studies which proposed exclusion from Gratiolaceae of four genera: Capraria, Limosella, Lindenbergia e Stemodiopsis. In this way, family Gratiolaceae is monophyletic and comprises the genera Achetaria, Bacopa, Conobea, Dopatrium, Gratiola, Hydrotriche, M ecardonia, Otacanthus, Philcoxia, Scoparia, Stemodia e Tetraulacium. Among these, in addition to Tetraulacium (a monospecific genus), other monophyleti and strongly supported genera are Gratiola, Mecardonia e Scoparia. The results suggest merging Achetaria and Otacanthus into a single genus. The same treatment has been suggested based on morphologic and palynologic characters. In the Scoparia clade a correlation is apparent between the position of species and its geographic distribution. The species with basal position (S. dulcis) has wide distribution, followed by S. montevidensis, with narrower distribution, covering the southern states and reaching M ato Grosso and part of Amazon. S. pinnatifida and S. ericaceae, in more derived condition, have distributions restricted to the south of Brazil. Bacopa is a paraphyletic genus, inclusion of Conobea scoparioides being required to reach monophyly. Conobea multifida is phylogenetically related to Scoparia and a group of Stemodia. The analysis failed to allow a reliable establishment of relationships between Tetraulacium and other genera. Gratiola is monophyletic and strongly linked to Achetaria, Otacanthus and a group of Stemodia. The latter genus is polyphyletic, the following phylogenic links having been observed: Stemodia vandellioides -M ecardonia; S. stellata -Philcoxia; (S. durantifolia, S. glabra, S. maritima, S. microphylla, S. veronicoides) (Achetaria, Otacanthus); (S. foliosa, S. trifoliata e S. verticillata) (Scoparia, Conobea multifida). S. maritima is the type species in the genus and only S. durantifolia and S. glabra emerged in the same clade with S. maritima. S. microphylla and S. veronicoides comprise a strongly supported clade, which is further supported by.


lamiales gratiolaceae lamiales gratiolaceae scrophulariaceae filogenia molecular molecular phylogeny scrophulariaceae

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