Joachim Thiede

Phylogenetic analysis of Sesuvioideae (Aizoaceae) inferred from nrDNA internal transcribed spacer (ITS) sequences and morphological data

The phylogeny of the four genera of Aizoaceae subfamily Sesuvioideae (Sesuvium, Cypselea, Trianthema and Zaleya) is elucidated employing internal transcribed spacer (ITS) sequences and 23 morphological characters. Phylogenetic analysis based on ITS sequences and a combined molecular-morphological analysis provide largely congruent results. The monophyly of Sesuvioideae and its close relationship to Aizooideae s.l. and Mesembryanthemoideae is confirmed. Zaleya is placed within Trianthema and Cypselea within Sesuvium by ITS analysis, but in the combined analysis, Zaleya forms an unresolved polytomy with the two Trianthema clades and Cypselea, as well as two Sesuvium species, remain unresolved. Sesuvium sesuvioides and S. hydaspicum, previously treated as synonyms, are closely related, but molecular data do not support conspecifity. The Trianthema triquetra complex needs further intensive study because the African T. triquetra sample is closer to the NE African-Arabian T. sheilae than to Australian samples of T. triquetra. The close relationship of four species of Trianthema (T. patellitecta, T. rhynchocalyptra, T. megasperma, and T. pilosa) from Australia based on molecular data is supported morphologically by the exclusive possession of a well-developed indumentum in these taxa.

Identity of Tetragonia pentandra and taxonomy and distribution of Patellifolia (Chenopodiaceae)

Abstract Thulin M., Rydberg A. & Thiede J.: Identity of Tetragonia pentandra and taxonomy and distribution of Patellifolia (Chenopodiaceae). — Willdenowia 40: 5–11. — Online ISSN 1868-6397;

Testa sculpture in the genus Frailea (Cactaceae)

The primary sculpture of the seed surface in the genus Frailea (Cactaceae) is characterized by a ± flat outer periclinal wall and the presence of an usually eccentric papilla. Papilla morphology differs mainly in size and breadth:length ratio. Seeds of different species (groups) are characterized by special patterns in the arrangement of short and long papillae on the surface, thus providing a useful tool for taxonomic studies in Frailea. The seeds of Frailea castanea possess branched papillae, a character restricted in this genus to this species. Moreover, such papilla morphology seems to be unique for the seed epidermis in spermatophytes. The possible function of the papillae is discussed.

Transfer of Polianthes geminiflora into Agave (Asparagaceae): new combinations (Nomenclature of Agave II)

Abstract Govaerts R. & Thiede J.: Transfer of Polianthes geminiflora into Agave (Asparagaceae): new combinations (Nomenclature of Agave II). — Willdenowia 43: 331–333. December 2013. — ISSN 0511-9618;

The International Organization for Succulent Plant Study (IOS): Its Role and Potential Services to the International Scientific Community

IOS, a scientific member of the International Union of Biological Sciences, was officially established at the Stadtische Sukkulenten-Sammlung in Zurich, Switzerland, in 1950. The IOS is presented, with emphasis on the structure of the organisation, its congresses, publications, conservation activities, and its potential services to the international scientific community. An address list of the current IOS board members and section co-ordinators is provided.