Phylogenetic analysis of Mexican and Central American Pinguicula (Lentibulariaceae) based on internal transcribed spacer (ITS) sequence

Abstract

ABSTRACT. The internal transcribed spacer (ITS) region of 18S-26S nuclear ribosomal DNA (nrDNA) in 36 species of Pinguicula (Lentibulariaceae) in Mexico and Central America, most of which are endemic to Mexico, was sequenced. Based on the ITS results, those species of Pinguicula studied were divided into three clades. In general, these cledes do not agree with the current conventional classification proposed by various authors except for Clade I. Clade I includes only two species belonging to section Isoloba, which are widely but sparsely distributed in Mexico and Central America. Clade II included 18 species, which have been conventionally classified in the sections Heterophyllum (six species), Longitubus (three species), Orcheosanthus (eight species), and Temnoceras (one species). Clade III included 16 species, which have been conventionally placed in section Agnata (four species), Crassifolia (four species), Heterophyllum (two species), Microphyllum (three species) and Orcheosanthus (three species). Clade II is widely distributed in the Sierra Madre Occidental, the Sierra Madre del Sur to the southern part of the Sierra Madre Oriental regions and extends down south to Honduras, while the species in clade III were mostly confined to the northern part of the Sierra Madre Oriental regions. In general, the ITS results were largely consistent with biogeographic patterns, but showed disagreements with the current morphological classification.

Phylogenetical Position versus Pollination Syndromes: Floral Trichomes of Central American and Mexican Pinguicula

“…The general topology of the ITS phylogenetic tree obtained in this study is, in general, congruent with the phylogenetic reconstructions of the Pinguicula genus based on ITS sequences from previous papers [51,85]. We recovered two major clades of Central American and Mexican species: the P. emarginata-P. moctezumae clade and P. agnata-P. gigantea clade, as well as taxon P. albida, corresponding to clades VII, VIII, and IX, respectively, according to Shimai et al [51].…”

“…The position of P. esseriana was unresolved in our analysis. Shimai et al [51,85], in previous analyses based on ITS sequences, placed P. esseriana in clade III/VIII (which corresponds to the P. agnata-P. gigantea clade in this work) with 52% and 57% bootstrap support, respectively. P. esseriana has long-spurred and colored flowers with visible yellow blotches at the entrance to the spur, indicating psychophily pollination syndrome.…”

Biogeographical patterns and speciation of the genus Pinguicula (Lentibulariaceae) inferred by phylogenetic analyses

“…Degtjareva et al [42] and Kondo & Shimai [43] analysed taxa mainly from the temperate Northern Hemisphere using the internal transcribed spacer (ITS) region, and they showed that taxa forming rootless hibernacula in the section Pinguicula were monophyletic. Shimai & Kondo [44] analysed the ITS (ITS-1, 5.8S, and ITS-2) regions of 36 species from Mexico and Central America and suggested that the species were monophyletic, although Casper [3] had divided them into three subgenera. Overall, those phylogenetic analyses were not consistent with the morphology-based classification.…”

Disentangling Phylogenetic Relationships in a Hotspot of Diversity: The Butterworts (Pinguicula L., Lentibulariaceae) Endemic to Italy

“…[14] by means of ITS region (nuclear internal transcribed spacers and small ribosomal gene, ITS T , nrDNA). The ITS T resulted much more informative than plastid markers, and was also used in a couple of studies focused on the species from Northern hemisphere [15] and focused on central American and Cuban taxa [16, 17]. In the above-cited studies, a few Italian endemic species, such as P .…”

“…Our marker choice is supported by: (1) high variability and discriminating capabilities of this molecular marker among Pinguicula taxa as already shown by Degtjareva et al . [14], Kondo & Shimai [15], Shimai & Kondo [16] and Shimai et al . [17]; (2) a complete GenBank nrDNA- Pinguicula database to be used for an exhaustive phylogenetic reconstruction; (3) completeness of information as a consequence of the biparental inheritance of nrDNA [6, 26, 27, 28].…”