DNA barcoding to analyse taxonomically complex groups in plants: the case of Thymus (Lamiaceae)

We evaluated the utility of the core barcode regions (matK and rbcL) and the plastid intergenic spacer trnH‐psbA to distinguish between Thymus 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 Thymus capitatus forms a well‐defined ‘barcoding gap’ compared with the other taxa. The identification problems observed in the other Thymus 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 Thymus spp. do not reflect real biological and molecular species boundaries. If this is the case, the taxonomy of Thymus 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.     

Taxonomy of the Poa laxa group,including two new taxa from Arctic Canada and Greenland,and Oregon,and a re‐examination of P. sect. Oreinos (Poaceae)

The Poa laxa Haenke species group, comprising four alpine–arctic taxa in P. sect. Oreinos, has a complicated and confusing taxonomic history. Here we re‐examine the taxonomy of the group and section based on sequences of three plastid and two nuclear ribosomal DNA markers. Poa laxa s.l. resolved in a clade with species of sections Abbreviatae, Oreinos, Stenopoa, and Tichopoa. In the plastid analyses, Poa laxa s.s. (type of sect. Oreinos) was placed in a subclade with P. glauca and other sect. Stenopoa species, while all other P. laxa s.l. taxa were placed in a subclade with species of sect. Abbreviatae. We maintain P. laxa s.s. (mainly 2n = 28) of west–central Europe in sect. Oreinos, while the other P. laxa s.l. taxa from northern Europe and North America (all 2n = 42 or higher ploid) are referred to P. sect. Abbreviatae. In North America only one collection of the northern European P. flexuosa subsp. flexuosa is accepted (Greenland, Jensen's Nunatakker), and P. flexuosa subsp. fernaldiana is accepted based on populations in eastern Canada and northeast USA. A new subspecies, P. flexuosa subsp. consauliae, is described from eastern Arctic Canada and Greenland; its variable morphological characteristics suggest introgression with P. glauca and it is predicted to be apomictic. Rocky Mountain P. laxa subsp. banffiana is treated as P. banffiana. Oregon material formerly considered to belong to P. laxa s.l. is named P. wallowensis. Poa sect. Oreinos is thus found to be polyphyletic, and is here emended to comprise only three continental European species, including P. laxa. Lectotypes are designated for P. aspera var. laxiuscula, P. fernaldiana, P. flexuosa, and P. laxa var. debilior. New chromosome numbers are reported for P. flexuosa subsp. consauliae (ca 2n = 42), and P. glauca (2n = 63) from Baffin Island. A key to the species and subspecies found in North America is given.     

A new species of Anthemis sect. Hiorthia (Asteraceae) from SE Sicily

A new species of Anthemis sect. Hiorthia (Asteraceae) is described from Sicily. This taxon, named A. piagnattiorum, is confined to a restricted area of the Hyblaean territory (SE Sicily), in the Natural Reserve of Cava Grande (Cassibile, Siracuse), where it takes shelter on carbonate rocky habitat and participates, with other Sicilian endemic taxa, to the composition of a termophilous chasmophytic community (Putorio calabricae–Micromerietum microphyllae).     

Morphometric study of the complex Moehringia sect. Pseudomoehringia McNeill from the western Mediterranean

Moehringia. sect. Pseudomoehringia McNeill is endemic to the western Mediterranean, having its origin and diversification centre in the Iberian Peninsula and mountains of northern Morocco. Both the relationship with the genus Arenaria as well as the taxonomy within the section have been largely controversial. To disentangle these issues, we conducted a morphometric study using herbarium material. We measured 12 relevant morphological traits from 148 selected herbarium sheets. Data were analyzed using different statistical methods: general linear models, multiple factorial analysis and linear discriminant analysis. We found significant differences between Arenaria balearica and the rest of the genus Moehringia taxa. Within this genus, we identified three well-discriminated species: Moehringia fontqueri, M. glochidisperma and M. intricata. Within M. intricata complex, we discerned virtually no differences amongst most of the subspecies (intricata, giennensis and tejedensis) with the exception of subsp. castellana. We propose: (i) to maintain A. balearica separate from Moehringia sect. Pseudomoehringia; (ii) to consider three species in the section Pseudomoehringia: M. fontqueri, M. glochidisperma and M. intricata; (iii) to recognize only two subspecies within M. intricata complex: subsp. intricata and subsp. castellana. To clarify the taxonomy of this threatened group is of great interest because it might help to prioritize conservation measures.     

Centaurea rahiminejadii sp. nov. and a new record in the genus Centaurea (Asteraceae,Cardueae–Centaureinae) from Iran

A new species, Centaurea rahiminejadii Negaresh (Asteraceae) in C. sect. Cynaroides Boiss. ex Walp., is described and illustrated from the Kermanshah Province, west Iran. It is morphologically similar to Centaurea regia Boiss. subsp. regia. Diagnostic morphological of this and closely related taxa are discussed and presented. The ecology, habitat and conservation status of the new species are also described. In addition, Centaurea regia subsp. cynarocephala (Wagenitz) Wagenitz is reported as a new record to the flora of Iran. Finally, the geographic distribution of the new species and closely related species is presented and mapped.     

A revision of European taxa ofHyacinthoides sectionSomera (Hyacinthaceae) on the basis of multivariate analysis

Cluster analysis and principal components analysis were used to investigate patterns of morphological variation among specimens of European species of sect.Somera of the genusHyacinthoides (Hyacinthaceae). The results are clearly consistent with the existence of four species (H. italica, H. paivae, H. reverchonii andH. mauritanica). It is proposed that the latter be considered to comprise two subspecies,H. mauritanica subsp.mauritanica andH. mauritanica subsp.vincentina (comb. nov.). A key is presented, together with distribution maps for the five taxa.     

Palynological investigations on some Hypericum taxa (Hypericaceae) growing naturally in Turkey

This study examined the detailed pollen morphological structures of sixteen Hypericum taxa (four endemic, twelve non endemic) including eight sections showing the natural distribution in Turkey: H. sect. Ascyreia (H. calycinum L.), H. sect. Heterophyllum (H. heterophyllum Vent.), H. Sect. Taeniocarpium (Hypericum confertum Choisy subsp. confertum, H. venustum Fenzl, H. linaroides Bosse), H. sect. Drosocarpium (H. montbretii Spach, H. bithynicum Boiss.), H. sect. Crossophyllum (H. adenotrichum Spach, H. orientale L.), H. sect. Olympia (H. olympicum L. subsp. olympicum), H. sect. Origanifolia (H. origanifolium Willd., H. avicularifolium Jaub and Spach subsp. depilatum (Freyn and Bornm.) Robson var. depilatum, H. avicularifolium Jaub. and Spach subsp. byzantinum) and H. sect. Hypericum (H. tetrapterum Fries, H. perforatum L., H. triquetrifolium Tura). These taxa were studied under light microscope and scanning electron microscope for the first time. Of the taxa studied, H. tetrapterum has the smallest pollen grains (on average 15.85–17.20 × 15.45–16.05 μm); and H. olympicum subsp. olympicum the largest grains (on average 22.90–23.10 × 21.40–22.10 μm). The pollen grains of 15 taxa are subprolate and one taxon is prolate-spheroidal. The regular pollen grains of all 16 taxa are 3-zonocolporate. Ornamentation is microreticulate; lumina regularly spaced in eight taxa, tectum perforatum; tectal perforations regularly spaced in seven taxa and tectum perforatum; and tectal perforations grouped together in one taxon. Endoaperture is cruciform porus, with short lateral and meridional extensions in ten taxa, cruciform porus, transversally elongated, with very small lateral extensions in one taxon and lalongate colpus in five taxa. Basic pollen types are ten taxa in type X, five taxa in type IV and one taxon in type II.     

Scrophularia attariae and S. maharluica spp. nov. (Scrophulariaceae) from south Iran

Two new species of Scrophularia L. sect. Tomiophyllum Benth., S. attariae Ranjbar & Rahchamani and S. maharluica Ranjbar & Rahchamani, are described and illustrated from Fars Province, south Iran. The diagnostic morphological characters of these species and closely related taxa are discussed. The distribution, ecology and conservation status of the new species are also described. The value and utility of stem indumentum and leaf stomata is evaluated as an additional source of information for their taxonomy. Finally, an identification key and distribution map for the new taxa and related species are presented.     

Morphological and genetic diversity within Pilosella hoppeana aggr. (Asteraceae) in Italy and taxonomic implications

Morphological variation, ploidy level and genetic diversity have been studied on 10 populations of the Pilosella hoppeana aggr. from the Alps, Abruzzo, Calabria and Sicily. Chromosome counts showed that the plants from Abruzzo and those from Sicily are tetraploid (2n = 36); they are assigned to P. hoppeana subsp. macrantha. The plants from the Alps (P. hoppeana subsp. hoppeana) and those from Calabria are diploid. The Calabrian populations, previously included in P. hoppeana subsp. macrantha, are shown to belong to a separate species, P. leucopsilon. The principal component analysis, based on 25 morphological characters, allowed distinguishing clearly four groups. An allozyme study using 10 enzyme systems revealed 7 polymorphic loci with a total of 20 alleles, some of them exclusive at regional level, others shared between populations showing similar morphological features. The genetic differentiation between populations was relatively high. The obtained dendrogram supports recognition of the morphologically defined taxa.     

A new species of Brassica sect. Brassica(Brassicaceae) from Sicily

Among the suffruticose cabbages of Brassica sect. Brassica, a new species from Sicily, named B. raimondoi, is described and illustrated. It is a chasmophyte restricted to some steep limestone cliffs near Taormina (NE Sicily) and is morphologically related to B. incana, with which it shares densely hairy, broad, amplexicaul leaves and winged petioles, but differs principally in its white corolla, larger floral pieces, more developed stigmatic papillae, shorter siliquae with keeled valves and a smaller, seedless beak, smaller seeds differing in testa microsculpture. A key for the identification of the currently known Sicilian taxa of the section is provided.     

Ecogeographical differentiation patterns inAdonis sect.Consiligo (Ranunculaceae)

Adonis sect.Consiligo is split into three subsections based on morphology, growth pattern, pollen and fruit morphology. For all species distribution maps are provided and discussed with regard to their ecology and climatic requirements. These data reveal additional characters that support the classification of the taxa. Most species of the section grow in continental Eurasiatic steppes and mountain steppe habitats. Only the species of subsect.Amurenses grow in Far Eastern temperate forests and prefer a more oceanic climate. The taxonomic position of these strongly divergent species is supported by the distributional and ecological data. The evolution ofAdonis sect.Consiligo occurred under strong climatic control. During evolution the taxa could only slightly widen their ecological amplitude and, thus, ecology remained rather stable except that of the subsect.Amurenses. Ecological and distributional data can be used to validate taxonomy and phylogeny and reveal additional informations.     

First record of Ribes uva-crispa L. (Grossulariaceae) from the Madonie Mts., a new species of the Sicilian flora

Abstract

In this study, a first record of Ribes uva-crispa L. (Grossulariaceae) – a new species of the Sicilian flora – from the Madonie Mts. is reported. The autochthonous and relict new population of Ribes uva-crispa L. (Grossulariaceae) is found on Mount Carbonara (Madonie Mts., North-Central Sicily), which is several hundred kilometers away from the Central Apenninic and the South Mediterranean locations of its distribution range. R. uva-crispa shows a distribution similar to other taxa extending from the Euro-Asiatic area to the mountains of North Africa with disjunct populations on the main Sicilian reliefs (Madonie and Nebrodi Mts.), testifying ancient phytogeographical connections. This noteworthy record adds a new species – as well as a new genus and new family – to the vascular flora of Sicily. Based on the morphological characters, the population found is to be referred to Ribes uva-crispa L. subsp. austro-europaeum (Bornm.) Bech var. glanduligerum (Lindberg) Maire.     

Geographical Distribution of Diploid and Tetraploid Cytotypes of Thymus sect. Mastichina (Lamiaceae) in the Iberian Peninsula, Genome Size and Evolutionary Implications

The occurrence of diploid and tetraploid cytotypes in Thymus section Mastichina (Lamiaceae) was investigated by chromosome counting and flow cytometric measurements of DNA content. To cover the entire native distribution of the section across the Iberian Peninsula, plant material was sampled from 29 populations, representing all three taxa (Thymus albicans, T. mastichina subsp. mastichina and T. mastichina subsp. donyanae). We provide first estimates of genome size for taxa of this section. Analyses revealed the existence of new cytotypes in T. mastichina subsp. mastichina (2n?=?2x?=?28, 30) and confirmed the existence of previous ones (2n?=?4x?=?56, 58, 60). We also confirmed the presence of exclusively diploid cytotypes (2n?=?2x?=?30) in the southwestern Iberian endemics T. albicans and T. mastichina subsp. donyanae. We conclude that the southwestern Iberian Peninsula acted as a Pleistocene glacial refugium that may have permitted speciation processes within this section. Several hypotheses concerning these processes and the origin and distribution of the studied taxa are discussed.     

Phytochemical Profile and Antioxidant Activity of the Aerial Part Extracts from Matthiola incana subsp. rupestris and subsp. pulchella (Brassicaceae) Endemic to Sicily

As part of a project aimed at investigating the Matthiola taxa endemic to Sicily (Italy), this study focused on Matthiola incana, an edible species used in the traditional medicine of various countries. Herein, the characterization of phenolic and volatile compounds, the antioxidant capacity in vitro (1,1-diphenyl-2-picrylhydrazil (DPPH), reducing power and Fe²⁺ chelating activity assays) and the toxicity test (Artemia salina lethality bioassay) of the hydroalcoholic extracts from the aerial parts of M. incana subsp. rupestris from Mt. Pellegrino (Palermo) and Mt. Erice (Trapani), and of M. incana subsp. pulchella are reported. The results are compared with those previously shown for M. incana subsp. incana, to achieve a comprehensive overview of the three subspecies. The HPLC-PDA/ESI-MS and SPME-GC/MS analyses led to the identification of 13 phenolics and 54 volatile compounds. Differences in the qualitative-quantitative profile of these phytochemicals have been highlighted between the M. incana subspecies. The antioxidant tests showed different activity for the extracts, which were found to possess better chelating properties. At last, none of the tested extracts displayed toxicity against brine shrimp larvae. These findings enrich the knowledge on the Matthiola taxa growing wild in Sicily, both from the strictly systematic point of view and for the possible applications as sources bioactive compounds that can be used in the nutraceutical field.     

RAD sequencing,morphometry and synecology clarify the taxonomy of the Melica ciliata (Poaceae) complex in France and Poland

Melica (Poaceae) consist of about 92 species distributed across temperate regions of the world. Within section Dalycum, Melica ciliata sensu lato forms a taxonomic complex of several species and subspecies with clinal morphological variation causing conflicting identifications. To resolve taxonomic confusion, we used three complementary approaches, through molecular, morphological, and phytoecological analyses. The double-digest restriction-associated DNA markers significantly support the monophyly of three taxa: (i) the Mediterranean Melica magnolii, (ii) the Eurasian Melica transsilvanica subsp. transsilvanica, and (iii) the west-European M. ciliata subsp. glauca. This differentiation is corroborated by the analysis of 22 morphometric variables. Furthermore, phytoecological analysis of 221 floristic inventories revealed habitat distinctions among these taxa. Our approach of integrative taxonomy argues for a specific distinction for these three taxa, and we include a key to separate these forms. These new molecular data on the section Dalycum, subsection Ciliatae, call for further phylogenetic analyses including samples of M. ciliata subsp. ciliata and other East-Mediterranean and South African taxa.     

Buchwaldoboletus lignicola (Boletaceae), a rare basidiomycete from Europe

Buchwaldoboletus lignicola is a rare basidiomycete with fragmented distribution in Europe. The taxonomy, ecology and distribution of this species is reported. The new locality from central Sicily widens the area of distribution of B. lignicola in Europe.