Ralph Mangelsdorff

• Goethe University Frankfurt

In the present study, the mycobiomes of two soils with different ecological conditions located in Benin (West Africa) were investigated by environmental sequencing (Illumina MiSeq) of the ITS2-region of ribosomal DNA to gain information about the influence of pedological stratification on fungal diversity. For each soil depth and horizon, fungal di...

Cercosporoid fungi (Mycosphaerellaceae, Mycosphaerellales, Ascomycota) are one of the largest and most diverse groups of hyphomycetes causing a wide range of diseases of economically important plants as well as of plants in the wild. Although more than 6000 species are known for this group, the documentation of this fungal group is far from complet...

Crosses between Schlumbergera species have been known since the 19th century. In almost all crosses, either S. truncata, S. russelliana, S. orssichiana or S. opuntioides are involved. The Schlumbergera species S. kautskyi and S. microsphaerica have rarely, or even not at all, been used in hybridization. The monograph by McMillan & Horobin (1995) on...

Species of tropical tar spot fungi (Phyllachorales, Ascomycota) are obligate biotrophic plant parasitic fungi associated with living leaves of a wide range of families of host plants, mainly in tropical and subtropical regions. In this study, samples of tropical tar spot fungi were collected in forests in Costa Rica and Panamá. To identify taxa, we...

Combined molecular and morphological analyses demonstrate that a number of small-flowered Caribbean Asclepiadoideae of hitherto uncertain affiliation form two independent lineages in Asclepiadeae-Gonolobinae, and not, as previously assumed, in the Metastelmatinae. One lineage is described as the new genus Anemotrochus, which includes the widespread...

Abstract— Analyses of cpDNA using maximum parsimony, maximum likelihood and Bayesian inference reveal that Metastelma is polyphyletic in its present circumscription. Two species are transferred to Tassadia as T. richardiana and T. stricta . One species, M. eggersii, is retrieved as a member of subtribe Gonolobinae rather than Metastelmatinae, and s...

The occurrence of rust fungi (Basidiomycota) infecting vascular plants on 14 sites in western Panama differing in altitude, climate, and vegetation type was analyzed. Three vegetation-types are investigated: (1) Disturbed sites where Asteraceae, Fabaceae, and Poaceae are most speciose, (2) slightly disturbed high canopy forests with sparse herbaceo...

Amorphophallus titanum was succesfully crossed with A. variabilis. One of the resulting seedlings is here presented as a new cultivar A. 'John Tan'.

Species richness in different groups of microfungi causing disease symptoms on above-ground plant organs is analyzed based on checklists and databases of five tropical regions in the Americas and two regions outside the tropics in North America. In addition, primary data on plant parasitic microfungi collected in natural habitats in western Panama...

A new semi-succulent species of Euphorbia (Euphorbiaceae), E. erythrocucullata, is described from SW Madagascar. The taxon is placed in the subgenus Lacanthis Raf. and grouped with E. pedilanthoides Denis; placement in this group is discussed.

A new species, Ceropegia yemenensis Meve & Mangelsdorff (Asclepiadoideae-Ceropegieae), from the province of Damar in northern Yemen, is described and illustrated. The tiny twiner with fleshy roots shares some characters with C. ahmarensis and C. stenantha from East Africa. Including this new species, the flora of Yemen now contains 11 Ceropegia spe...

Two new species of the genus Amorphophallus (Araceae) are described from Madagascar. An updated key to the Malagasy species is presented.

A new semi-succulent species of Euphorbia (Euphorbiaceae), E. erythrocucullata, is described from SW Madagascar. The taxon is placed in the subgenus Lacanthis Raf. and grouped with E. pedilanthoides Denis; placement in this group is discussed.