Iridoid glucosides in the genus Veronica (Plantaginaceae) from New Zealand.

Four simple iridoid glucosides, three known esters of catalpol, seven esters of aucubin, and two phenylethanoids were isolated from Veronica hookeri (syn. Hebe ciliolata; Plantaginaceae). Of these, none of four aromatic (p-methoxybenzoyl, isovanilloyl, veratroyl, caffeoyl) 6-O-esters of aucubin and 6″-O-benzoyl mussaenosidic acid, had been reported from nature before. Similarly, three simple iridoid glucosides, two esters of 6-O-rhamnopyranosylcatapol, and two phenylethanoid glucosides, as well as 1-O-benzoyl-3-α-glucuronosylglycerol, and 1-O-ß-benzoyl rutinoside were isolated from Veronica pinguifolia (syn. Hebe pinguifolia). The compound 3″-O-benzoyl-2″-O-caffeoyl 6-O-rhamnopyranosylcatalpol had not been reported previously. The pattern of the structural features of the iridoid glucosides is overlaid onto the latest molecular phylogenetic framework of Veronica sects. Hebe and Labiatoides, and discussed in the context of evolutionary trends.

Iridoid and phenylethanoid glycosides in the New Zealand sun hebes (Veronica; Plantaginaceae).

The sun hebes are a small clade of New Zealand Veronica formerly classified as Heliohebe. The water-soluble compounds of Veronica pentasepala, Veronica raoulii and Veronica hulkeana were studied and 30 compounds including 15 iridoid glucosides, 12 phenylethanoid glycosides, the acetophenone glucoside pungenin, the mannitol ester hebitol II and mannitol were isolated. Of these, five were previously unknown in the literature: dihydroverminoside and 3,3',4,4'-tetrahydroxy-α-truxillic acid 6-O-catalpyl diester, named heliosepaloside, as well as three phenylethanoid glycoside esters heliosides D, E and F, all derivatives of aragoside. The esters of cinnamic acid derivatives with iridoid and phenylethanoid glycosides and an unusually high concentration of verminoside were found to be the most distinctive chemotaxonomic characters of the sun hebes. The chemical profiles of the species were compared and used to assess the phylogenetic relationships in the group.

Iridoid and phenylethanoid glucosides from Veronica lavaudiana.

From an extract of Veronica (sect. Hebe) lavaudiana we have identified mannitol and isolated 11 iridoid glucosides, the carbohydrate ester hebitol II, and four phenylethanoid glycoside esters. Five of the iridoid glycosides are new; of these, lavaudiosides A, B, and C (2a, 3a, and 4) are 1-mannityl esters of 8-epiloganic acid, while 7e and 7f are 6'-O-caffeoyl derivatives of catalpol. The new phenylethanoid glycoside esters, heliosides A, B, and C (8b-d), are 6'-xylosyl derivatives of aragoside. The structures of the new compounds were elucidated mainly by spectroscopic analysis, but also by chemical degradation. We also demonstrated that the structures of the known glycosides globularitol and hebitols I and II should be revised. These compounds are derivatives of mannitol and not glucitol as previously believed.

First phylogenetic and biogeographical study of the southern bluebells (Wahlenbergia, Campanulaceae).

Wahlenbergia is a largely southern hemisphere genus of at least 260 species; within Campanulaceae only Campanula is larger. This first phylogeny of Wahlenbergia was reconstructed using about 20% of the 260 species in the genus based on the nuclear ribosomal ITS marker and the chloroplast trnL-F marker with samples from South Africa, Europe, Australia and New Zealand. Wahlenbergia was confirmed to be non-monophyletic, though most of the species form a clade. Our tree topology and date estimates indicate that Wahlenbergia diverged in South Africa about 29.6 mya, then dispersed to Australasia about 4.8 mya, thus indicating the radiation of Wahlenbergia occurred relatively recently. Radiations occurred in both of these main centres; there are currently about 170 species in South Africa and 45 species and subspecies in Australasia. New Zealand species comprise two clades, both rooted within the Australasian clade. We thus propose two dispersals from Australia to New Zealand, one leading to a radiation of species with the rhizomatous herbaceous growth form ca. 1.6 mya, and the other leading to a radiation of species with the radicate growth form 0.7 mya. Dispersals from Australia to New Zealand match the expected direction, following the west wind drift and ocean currents. The herbaceous growth form was shown to be ancestral for the genus as a whole, and polyploidy has been a mechanism of the evolution of the genus in Australasia.

Correlated evolution of sexual system and life-history traits in mosses.

In mosses, separate and combined sexes are evolutionarily labile, yet factors selecting for this variation are unknown. In this study, we investigate phylogenetic correlations between sexual system and five life-history traits (asexual reproduction, chromosome number, gametophore length, spore size, and seta length). We assigned states to species on a large-scale phylogeny of mosses and used maximum likelihood analyses to test for the correlations and investigate the sequence of trait acquisition. Mosses in lineages with separate sexes were significantly more likely to be large, whereas those in lineages with combined sexes had higher chromosome numbers. Moreover, evolutionary transitions to separate sexes were more likely to occur in lineages with small spores. There was no support for a correlation between asexual reproduction and separate sexes. These results suggest that sexual system evolution is influenced by traits affecting mate availability and the dispersal of gametes and spores, and provides evidence for the existence of syndromes of life-history traits in mosses.

Subfamilial relationships within Caryophyllaceae as inferred from 5' ndhF sequences.

DNA sequences of the 5' end of the chloroplast ndhF gene for 15 species of Caryophyllaceae have been analyzed by parsimony and neighbor-joining analyses. Three major clades are identified, with little or no support for monophyly of traditionally recognized subfamilies. The first of the three major clades identified (Clade I) is constituted by part of the subfamily Paronychioideae. It includes members of the tribe Paronychieae and members of tribe Polycarpeae. The second (Clade II) contains members of the Paronychieae exclusively. Tribe Paronychieae is thus apparently polyphyletic and tribe Polycarpeae is at least paraphyletic. The third clade (Clade III) includes members of subfamilies Alsinoideae and Caryophylloideae along with the genus Spergularia. The genus Scleranthus is also part of Clade III, while Drymaria groups with the other genera of tribe Polycarpeae in Clade II. We conclude that morphological characters previously used to delimit subfamilial groupings in the Caryophyllaceae are apparently unreliable estimators of phylogeny.