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A Dichotomous Key to the Genus Drosera L. (Droseraceae)
... In addition, studies of characters such as cytology (e.g. Kondo 1976;Kondo & Lavarack 1984), germination (Conran et al. 1997), pollen structure (Takahashi & Sohma 1982) and phytochemisty (Culham & Gornall 1994) have added to the overall understanding of relationships in the family, contributing to several proposed classification realignments (Marchant et al. 1982;Seine & Barthlott 1994;Schlauer 1996). ...
... In an attempt to reconcile their respective leaf microgland classifications, the data for their studies and ours are summarised at sectional level with the respective gland classifications indicated in Table 1. These character state distributions were then mapped onto a condensed sectional-level cladogram derived from the clades obtained by Rivadavia et al. (2003), using the sectional classification of Schlauer (1996) and the clade-exploration program MacClade 3.06 (Maddison & Maddison 1996). Phylogenetically useful patterns of character states were then discussed in terms of evolution within the family. ...
... ex All.: N.Marchant). The expanded data confirm this, with all taxa possessing these glands being members of the Bryastrum clade sensu Schlauer (1996) possessing these glands, as well as subgenus Coelophylla (D. glanduligera Lehm.) which was basal to the Bryastrum/Ergaleium clade pair. ...
Droseraceae germination and leaf gland and microgland character state patterns were re-examined in the light of new molecular phylogenetic relationships. Phanerocotylar germination is basal in the family, with cryptocotylar germination having evolved at least twice; once in Aldrovanda, and again in Drosera within the Bryastrum/Ergaleium clade. Gland patterns also support major clades; with the Bryastrum clade taxa having marginal and Rorella-type glands whereas the terminal branch of the Drosera clade had marginal glands and most of the clade possessed biseriate type 3 glands. The gland and germination patterns are supported by growth habit features, suggesting that the family and the main clades within Drosera in particular have undergone major adaptive radiations for these characters.
... Although several morphological characters can be used to distinguish species in Drosera (Schlauer, 1996), sometimes it is difficult to differentiate species using only morphological traits, especially in large and taxonomically complex genera such as this. In these cases, DNA is a useful tool to help with the identification of individuals new to the area (Darling & Blum, 2007;Calviño et al., 2018). ...
... The individuals were tentatively identified following a dichotomous key to the genus Drosera (Schlauer, 1996), and keys and descriptions in several floras of northern temperate regions (Webb, 1993;Lu & Kondo, 2001;Mellichamp, 2015), as most alien species naturalised in Nahuel Huapi National Park come from temperate areas of the Northern Hemisphere. Morphological characters used to distinguish species of Drosera are habit, leaf shape, presence or absence of stipules, inflorescence scape length and number of flowers, sepals and petals characteristics, style number and morphology, seed traits and presence of specialised organs, such as gemmae or tubers (Schlauer, 1996). ...
... The individuals were tentatively identified following a dichotomous key to the genus Drosera (Schlauer, 1996), and keys and descriptions in several floras of northern temperate regions (Webb, 1993;Lu & Kondo, 2001;Mellichamp, 2015), as most alien species naturalised in Nahuel Huapi National Park come from temperate areas of the Northern Hemisphere. Morphological characters used to distinguish species of Drosera are habit, leaf shape, presence or absence of stipules, inflorescence scape length and number of flowers, sepals and petals characteristics, style number and morphology, seed traits and presence of specialised organs, such as gemmae or tubers (Schlauer, 1996). The morphological characterisation was done based on the three available individuals. ...
Drosera L. (Droseraceae) is a genus of insectivorous plants distributed worldwide with 240 species, 40 of which are found in South America. In the temperate forests of Chile and Argentina the only species present is D. uniflora. In a peat bog in Nahuel Huapi National Park, Argentina, a new species of Drosera was found in February 2018. To identify the species, we used morphological characters, and in addition, we sequenced two individuals for the nuclear region ITS and the chloroplast gene rbcL. Other Drosera sequences for these molecular regions were downloaded from GenBank, and a phylogenetic analysis was done to confirm the morphological identification of the Patagonian individuals. Morphologically and genetically, the species found in Nahuel Huapi is D. rotundifolia, a mostly Northern Hemisphere species. This is an alien species to the region and is thought to have been transported to the bog by tourists that visit the area. The presence of an exotic species represents a threat to this particular ecosystem with high conservation value. Currently, the National Park is taking control actions order to remove all individuals of the recently detected species. This study represents the first report of an alien species of Drosera in southern South America growing in the wild. This potentially invasive species may not only have negative impacts on the natural peat bog habitats in southern Argentina and Chile, but may also reach bogs in other temperate parts of the world.
... The discovery of M in D. minutiflora (syn. D. parvula: Lowrie 2014: 620), D. pedicellaris, and D. sargentii suggests a close phylogenetic relationship between these taxa as deduced from morphological similarity before (Schlauer 1996;Lowrie 2014: 700 & 796). ...
... Lowrie (2014), in parentheses alternative classification followingSchlauer (1996). b P: plumbagin, M: ramentaceone, 0: no quinone detected c References * New/additional data from this study 1 Culham & Gornall 1994 2 Schlauer 2012 3 Länger et al. 1995 Fresh leaves of D. roseana, D. scorpioides, and D. pygmaea did not yield quinones, confirming gemmae and/or literature results. ...
A detailed study of 44 accessions representing 38 taxa (76% of the diversity known at present) of pygmy sundews (Drosera sect. Bryastrum) reveals the first naphthoquinone patterns in this lineage, in which previous studies have not yielded reliable evidence for naphthoquinones. While most samples do not display detectable amounts of naphthoquinones as previously reported for the group, ramentaceone is detected in three mutually related taxa, and both ramentaceone and its regio-isomer plumbagin is present in all accessions investigated of D. pulchella.
... When first discovered in flower, Drosera citrina was described by Lowrie (1989; initially mistaken for D. rechingeri, until correctly classified by Lowrie & Carlquist 1992) to be one of the most unique pygmy Drosera due to its striking flower color. The white-flowered D. nivea was denoted as its closest relative by Lowrie & Carlquist (1992), but considered to represent a variety of D. citrina by Schlauer (1996) -the latter classification was not adopted by most Drosera taxonomists (e.g., Lowrie 1998Lowrie , 2014Lowrie et al. 2017;Fleischmann et al. 2018). With the description of D. coalara by Lowrie (2014), another closely related taxon was added to this affinity of species from the northern sand plains of southwest Western Australia ( Fig. 1). ...
... Infraspecific classification might be more appropriate in this case than two separate species. Schlauer (1996) suggested to distinguish the two taxa on variety rank -however, in his concept that would suggest sympatry (which has never been observed so far), and so the rank of subspecies (i.e., allopatric distribution) might be more appropriate. However, in the present work, we distinguish both taxa on species rank, with D. coalara treated as conspecific with D. citrina. ...
The pygmy sundews (Drosera section Bryastrum) are the second-largest group of Australian Drosera in terms of species number following the tuberous sundews. According to the latest revisions (Fleischmann et al. 2018; Robinson et al. 2018) they currently comprise 51 species in southwest Western Australia and six named natural hybrids (Lowrie 2014; Lowrie et al. 2017). Within the pygmy Drosera, a wide range of flower colors can be found, ranging from pure white, various shades of pink, metallic orange, and red to yellow colors, quite often with bi- or rarely even tricolored petals (Lowrie 1989; Robinson et al. 2018). The color combination of lime yellow petals with white base has thus far been considered to be unique to D. citrina (Lowrie & Carlquist 1992; Lowrie 2014; Lowrie et al. 2017).
... Except D. pygmaea, other species in section Bryastrum have pentamerous flowers and are endemic to southwestern Australia. D. pygmaea has been placed in a different section owing to its unique distributary features and tetramerous flowers, 36,37 . This implies that tetramerous flowers are an autapomorphic character and would have evolved from the pentamerous flowers shared by other pygmy sundews. ...
... It is widely believed that Drosera has colonized itself in both the hemispheres 37 and Australia happens to be the center of diversity of Drosera species, where more than 80 species thrive [38][39][40] . Over 30 species are distributed in Northern Africa and half of the species are distributed in South Africa. ...
Background: Botanical carnivory is spread across four major angiosperm lineages and five orders: Poales, Caryophyllales, Oxalidales, Ericales and Lamiales. The carnivorous plant family Droseraceae is well known for its wide range of representatives in the temperate zone. Taxonomically, it is regarded as one of the most problematic and unresolved carnivorous plant families. In the present study, the phylogenetic position and biogeographic analysis of the genus Drosera is revisited by taking two species from the genus Drosera ( D. burmanii and D. Peltata ) found in Meghalaya (Northeast India).
Methods: The purposes of this study were to investigate the monophyly, reconstruct phylogenetic relationships and ancestral area of the genus Drosera , and to infer its origin and dispersal using molecular markers from the whole ITS (18S, 28S, ITS1, ITS2) region and ribulose bisphosphate carboxylase (rbcL) sequences.
Results: The present study recovered most of the findings by previous studies. The basal position of Droseraceae within the non-carnivorous Caryophyllales indicated in the tree topologies and fossil findings strongly support a date of origin for Droseraceae during the Paleocene (55-65 mya). Within the family Droseraceae, the sister relationship between Aldrovanda and Dionaea is supported by our ITS and rbcL dataset. This information can be used for further comparative and experimental studies.
Conclusions:Drosera species are best suited as model systems for addressing a wide array of questions concerning evolutionary dynamics and ecological processes governing botanical carnivory.
... As Drosera rotundifolia possesses good antiinflammatory activity due to the presence of flavonoids. Drosera magnifica is also prone to possess antiinflammatory mechanisms via their ability to inhibit reactive oxygen or nitrogen compounds [63][64][65][66][67] . ...
... Dietary flavonoid intake is associated with reduced gastric carcinoma risk in women, and reduced aero digestive tract cancer risk in smokers. So there may be chances that Drosera magnifica can be used to reduce carcinoma risk due to presence of both quinines and flavonoids [67][68][69][70][71] . Derivatives of quinones are common in biologically active molecules as an electron acceptor as well as for production of useful metabolites in aerobic respiration. ...
A long cycle of adaptation is going on in the ecosystem either it is a human being who adapted or a plant. Recently carnivorous
plants have taken the stage of adaptation. By not getting photosynthesis and nitrogen from the environment non carnivorous plants have adapted to carnivorous species. Researchers have discovered thousands of new species of carnivorous plants. Recently the social network photographs have revealed the third largest species of Droserea family that is Droserea magnifica. In this article, we have discussed Droserea magnifica, its discovery, habitat and its future prospects in relation to its phytochemistry and
pharmacology.
Keywords: Carnivorous, Droseraceae, Drosera magnifica, Phytochemistry, Pharmacology.
... and stated that the range expansion into Africa was important when considering glaciation and dispersion events in Drosera. Schlauer (1996), in a synoptic overview of Drosera, explained the aberrant occurrence in east (sic) Africa as resulting from an 'almost certainly recent -synanthropous? -range extension'. ...
The original set of botanical collections of the agronomist H.A. Homblé is conserved in the herbarium BR. Homblé was one of the first collectors (1911–1913) for the flora of Katanga, Democratic Republic of the Congo. Many Homblé specimens were described as taxonomic novelties; 107 tropical African plant species are named after him. Before his colonial career in Katanga, Homblé stayed about two years (1909–1911) in Guangxi, China.
His incompletely labelled Chinese collections were erroneously considered as collected in Katanga. This supposed African origin has led to confusion with regard to the identification, and even resulted in the description of four species believed to be new for science. This paper presents and discusses Homblé’s collection made in Guangxi, and
the assumed novelties in it. Drosera insolita is a synonym of the Asian Drosera lunata, widespread from India to Australia. Three other species are new synonyms. Caesalpinia homblei is a synonym of the pantropical Caesalpinia bonduc. Digitaria polybotryoides is a synonym of Digitaria abludens, a widespread species in tropical Asia. Grewia
katangensis is the only species that proved to be synonymous with an endemic species, Grewia cuspidatoserrata, only known from S Yunnan, and here reported as a new record for Guangxi. Lysimachia candida and Impatiens chinensis should be deleted from the list of the Congo Flora. The importance of careful specimen labelling and
label interpretation is discussed.
... Drosera sect. Ptycnostigma Planch., largely using style morphology, a lack of stipules, thickened roots, corolla size and the presence of cauline leaves as delimitations (Schlauer 1996). Seine & Barthlott (1994) treated D. cistiflora L. as a single taxon in section Ptycnostigma, with radially symmetrical marginal tentacles in the cauline leaves and a chromosome number of 2n = 60. ...
• Variation in plant breeding systems has implications for pollinator‐mediated selection on floral traits and the ecology of populations. Here we evaluate pollinator contribution to seed production, self‐compatibility and pollen limitation in different colour forms of Drosera cistiflora sensu lato (Droseraceae). These insectivorous perennial plants are endemic to fynbos and renosterveld vegetation in the Cape Floristic Region of South Africa and the species complex includes five floral colour forms (pink, purple, red, white and yellow), some of which are known to be pollinated by beetles.
• Controlled hand‐pollination experiments were conducted in 15 populations of D. cistiflora s.l. (2–4 populations per floral colour form) to test whether the colour forms vary in their degree of self‐compatibility and their ability to produce seeds through autonomous self‐fertilisation.
• Yellow‐flowered forms were highly self‐incompatible, while other floral colour forms exhibited partial self‐compatibility. Seed set resulting from autonomous selfing was very low, and pollinator dependence indices were high in all populations. Since hand cross pollination resulted in greater seed set than open pollination in 13 of the 15 populations, we inferred that seed production is generally pollen‐limited.
• Drosera cistiflora s.l. typically exhibits high levels of pollinator dependence and pollen limitation. This is unusual among Drosera species worldwide and suggests that pollinators are likely to mediate strong selection on attractive traits such as floral colour and size in D. cistiflora s.l. These results also suggest that the colour forms of D. cistiflora s.l. which are rare and threatened are likely to be vulnerable to local extinction if mutualisms were to collapse indefinitely.
... According to the topology found in the phylogenetic reconstruction of Rivadavia et al. (2012), ovoid seed shape is homoplastic, and taxa that would be classified as belonging to D. sect. Oosperma based on the section description provided by Schlauer (1996), can be found spread in D. sections Drosera, Brasiliae and Ptycnostigma. Hence, Drosera section Oosperma as circumscribed by Rivadavia (2003) is polyphyletic, as it additionally included four of the tetraploid Brazilian taxa, which belong to a different clade herewith classified as D. section Brasiliae. ...
The research presented in this paper concerned the micropropagation of Drosera anglica Huds. and D. intermedia Hayne. by direct organogenesis. The aim was to determine the minimum composition of medium for leaf fragments culture of both species in vitro. Murashi and Skoog (1962, MS) medium was used as a medium with the addition of two phytohormones: NAA and BA. The study was conducted on a BM control and its dilutions: ½ BM, ¼ BM, 1/8 BM, 1/16 BM, 1/32 BM. The effect of individual media concentrations on the growth of shoots, roots, the number of seedlings produced by a single explant and the colour of the seedlings were observed. Acclimatization to ex vitro conditions obtained in plant breeding was assessed. In addition, a leaf decontamination procedure was performed on the example of D. capensis L. to minimize losses in the culture material.
Observations have shown that the amount of mineral compounds in the medium has a significant impact on the development of the explants. As the concentration of the nutrient solution decreased, the diameter of rosettes decreased and the root length increased. At the lowest concentration of medium (1/32 BM) no signs of development were observed. 60 seedlings were transferred to ex vitro conditions. Survival rate was about 95%. The optimal variant for the breeding of both sundew species was the variant R2, and the obtained seedlings had the highest average weight. The minimal variant for the sundew breeding, given satisfactory results, was R4. This variant developed respectively for: D. anglica - 72.7% and D. intermedia - 66.7% of the biological material.
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