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Hamburg, Germany

Thiede J.,Schenefelder Holt 3 | Opel M.R.,University of Connecticut | Hammer S.A.,Sphaeroid Institute
Haseltonia | Year: 2010

In an older paper, Reznik (1957) studied flower pigments from 37 Conophytum samples and found three main pigments: one betaxanthin (in samples with yellow flowers) and two betacyanins (betanin 1 in samples with purple flowers and betanin 2 in one sample with rose-purple flowers), as well as 6 flavonols as co-pigments. Here, the results from Reznik (1957) and related older studies are compared with more recent morphological-phylogenetic studies (Opel 2005b) with regard to the agreement or deviation with respect to subdivisions of the genus Conophytum. The mutually exclusive distribution of two flavonols in Conophytum is phylogenetically informative: flavonol 1 is restricted to the basally diverging lineages of the Biloba Grade (including Conophytum taylorianum), and flavonol 2 was found in the group containing the remainder of Conophytum, probably indicating monophyly. In conjunction with phylogenetic data of Opel (2005b), floral pigment data suggest that Conophytum sect. Biloba could be provisionally recognized as a possibly paraphyletic assemblage comprising all members of the Biloba Grade including C. taylorianum but excluding C. herreanthus, and that sect. Herreanthus should encompass C. herreanthus only. © 2011 Cactus and Succulent Society of America. Source


Thiede J.,Schenefelder Holt 3
Bradleya | Year: 2015

For two recently published species of Polianthes, P. alboaustralis E.Solano & Ríos-Gómez and P. cernua Art.Castro, J.G.González & Aarón Rodr., binomials in Agave are proposed: Agave alboaustralis (E.Solano & Ríos-Gómez) Thiede comb. Nov. and Agave neocernua Thiede nom. Nov. Source


Four infraspecific taxa in Mediterranean Sedum (S. eriocarpum subsp. apertiflorum 't Hart, subsp. orientale 't Hart, and subsp. Spathulifolium 't Hart, and S. Litoreum var. creticum't Hart) were first invalidly published by Hart (1996) in Ot Sist. Bot. Dergisi 2(2), but later validated by Hart (2002) in Fl. Hellenica 2. The valid place and date of valid publication and the type is indicated for all four taxa. Source


Mifsud S.,Flat 5 | Stephenson R.,8 Percy Gardens | Thiede J.,Schenefelder Holt 3
Phytotaxa | Year: 2015

Plants of Sedum album (Sedum ser. Alba; Crassulaceae) from Malta (Maltese Islands) differ from previously known S. album plants in having very rarely formed inflorescences mostly without peduncular leaves and floral bracts, flowers in which (3–)5 stamens of one whorl, mostly of the antepetalous one, have dysfunctional and often abortive anthers and only the stamens of the other whorl having 5, dark maroon to blackish-brown, mostly indehiscent anthers at anthesis, pollen which is partly deformed and shrivelled, carpels without nectary scales, and fruits and seeds which remain undeveloped and sterile. The Maltese plants have apparently switched from generative to almost exclusively vegetative reproduction and are described as a new endemic subspecies Sedum album subsp. rupi-melitense. The local history, distribution, habitat, phenology, and conservation status of this new taxon (which is categorized as Critically Endangered according to IUCNRed List Criteria) are discussed. © 2015 Magnolia Press. Source


Thulin M.,Uppsala University | Thiede J.,Schenefelder Holt 3 | Liede-Schumann S.,University of Bayreuth
Taxon | Year: 2012

The phylogenetic position and circumscription of the disjunct African genus Tribulocarpus is investigated with DNA sequences from plastid rps16 and trnL-F, and nuclear ITS. Representatives from all four subfamilies of Aizoaceae are included in the analyses, most of them from Aizooideae and Sesuvioideae. The position of Tribulocarpus as sister to the rest of Sesuvioideae is confirmed, and we agree that the genus should be referred to this subfamily. Tetragonia retusa is found to be part of the Tribulocarpus clade with strong support. A new taxonomy of Tribulocarpus with two species is proposed and the new combination Tribulocarpus retusus is made. A lectotype is designated for Tetragonia somalensis. Tribulocarpus dimorphanthus, disjunctly distributed in south-western and north-eastern Africa, is retrieved as paraphyletic with regard to T. retusus, endemic in Somalia, as the latter is sister to the north-east African part of T. dimorphanthus only. Despite the genetic difference between the samples from the disjunct populations of T. dimorphanthus no morphological differences could be detected. Tribulocarpus dimorphanthus-T. retusus is suggested as an example of a progenitor-derivative species pair, where T. retusus has budded off from the north-eastern partial area of distribution of T. dimorphanthus. The compound and spiny fruits of T. dimorphanthus versus the simple and broadly winged fruits of T. retusus indicate a rapid adaptive shift from zoochorous trample burrs to anemochorous nuts. Source

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