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Publications (92)
Based on recent collections from Arunachal Pradesh (Northeast India), a new species of Gesneriaceae, Whytockia arunachalensis, Taram, D.Borah & Tag is described. It differs from the other species of WhytockiaW.W.S.m. by its extensive, dense and uniform indumentum over the entire plant and is closely related to the white, but smaller-flowered congen...
Der Afrikanische Kontinent (inkl. Madagaskar und die Komoren) ist relativ arm an Vertretern der Gesneriaceae. Afrikanische Gesneriaceen sind auch arm an typisch tropischen Bestäubungsmustern wie Vogel- und Fledermausblütigkeit. Während das letztere Syndrom völlig fehlt, gibt es nur zwei Arten, die klar das Syndrom der Vogelblütigkeit (Ornithophilie...
Die Familie der Gesneriaceae weist hinsichtlich Blütenformen, -farben, -größen und Bestäubungssyndromen eine enorme Vielfalt auf. Besonders interessant sind jene Fälle, bei denen sich innerhalb einer Gattung oder einer engen Verwandtschaftsgruppe verschiedene Bestäubungssyndrome und Anpassungen an bestimmte Tiergruppen herausdifferenziert haben – e...
Nachdem Stefan Vogel in den späten 1950er-Jahren bewiesen hatte, dass bei den Kesselfallenblumen von Ceropegia (Apocynaceae-Asclepiadoideae) winzige Fliegen als Bestäuber agieren (Mikromyiophilie), konnte er zwanzig Jahre später eine weitere und ganz spezielle Fliegengruppe als Bestäuber ausmachen: Pilzmücken (Mycetophilidae, Sciaridae u.a.). Vogel...
Bei den Monokotyledonen haben sich Ölblumen in zwei Familien entwickelt: Iridaceen und Orchideen. Bei ersteren (mit Trichom-Elaiophoren) zweimal, bei letzteren mindestens 10 mal voneinander unabhängig (sowohl Trichom- als auch Epithel-Elaiophoren). Wichtige Vertreter aus beiden Familien, die bereits von Stefan Vogel entdeckt wurden, werden näher da...
Ölblumen haben sich im Laufe der Evolution in 11 Pflanzenfamilien entwickelt und selbst innerhalb dieser Familien sind sie oft mehrfach und voneinander unabhängig entstanden. Im vorliegenden Artikel werden, aufbauend auf den morphologischen Analysen und Bestäubungsbeobachtungen von Stefan Vogel, wichtige Vertreter der Dikotyledonen vorgestellt. Die...
Nach der Entdeckung der Parfümblumen hat Stefan Vogel einen weiteren neuen Blumentypus erkannt und erforscht: die Ölblumen. Hier wird von den Blüten fettes Öl als Sammelgut angeboten, das in den sogenannten Elaiophoren gebildet wird. Das Öl wird von spezialisierten Bienen (Vertreter mehrerer Gruppen der Apidae-Apinae und zwei Gattungen der Melittid...
Mit der Entdeckung der „Parfümblumen“ (zahlreiche Orchideen sowie vereinzelt Gattungen und Arten der Araceae, Gesneriaceae, Euphorbiaceae und Solanaceae) und ihre Bestäubung durch hochspezialisierte, männliche Prachtbienen (Apidae-Euglossini) hat Stefan Vogel einen bahnbrechenden Beitrag zur Blütenökologie geleistet. Nachdem mehr als 250 Jahre lang...
Over the last two decades molecular phylogenetic research on Gesneriaceae has greatly advanced our understanding of species relationships and generic delimitations. It has allowed the proposal of a new classification of the family that is thought to reflect the natural relationships of the taxa better than traditional morphological classifications....
Blütendüfte hat man für lange Zeit als bloße Nebenprodukte des pflanzlichen Stoffwechsels gehalten, die ökologisch nur gelegentlich bzw. sekundär ausgenutzt werden. Stefan Vogel hat gezeigt, dass die Düfte in spezifischen Strukturen, den so genannten Osmophoren, gebildet werden. Für ihre Bildung ist Energie notwendig, die durch den Abbau von Stärke...
For the Gesneriaceae of India the consequences of revised generic circumscriptions and the new classification based on molecular phylogenetic work are summarised and outlined. An identification key, genus descriptions and some considerations on the biogeographic distribution of the genera in India are provided. The current genus count in India is 2...
Stefan Vogel war Vorreiter in der Untersuchung der Fledermausblütigkeit. Auf mehreren Reisen, zunächst nach Südamerika, später auch nach Westafrika und Südostasien, konnte er erstmals für einige Gattungen oder sogar Familien Fledermausbestäubung feststellen. Das Syndrom der Fledermausblütigkeit wird erläutert.
Stefan Vogel (1925– 2015) war einer der führenden Blütenökologen unserer Zeit. Die Bedeutung seines wissenschaftlichen Lebenswerkes, insbesondere die Erforschung der Beziehungen zwischen Blüten und Bestäubern (Blütenökologie), wird herausgestellt. Dieser erste Beitrag handelt von den „Stiltypen“ der Blüten (Bestäubungssyndrome), die Vogel im Zuge s...
Inflorescences of Araceae pollinated by cyclocephaline scarab beetles are visited frequently by a wide array of other arthropods that exploit floral resources without taking part in pollination, including earwigs, flies, and true bugs. To date, nothing is known about the cues these insect visitors use to locate the inflorescences and whether or to...
Besleria macropoda, a rare and poorly known gesneriad endemic to Costa Rica, was recently collected for the first time on the southern slopes of the Fila Costeña (Puntarenas Province, SE Costa Rica). The collection considerably widens the geographic distribution to the southeastern part of Costa Rica. Moreover, the following unique characters not p...
A new formal classification of Gesneriaceae is proposed. It is the first detailed and overall classification of the family that is essentially based on molecular phylogenetic studies. Three subfamilies are recognized: Sanangoideae (monospecific with Sanango racemosum), Gesnerioideae and Didymocarpoideae. As to recent molecular data, Sanango/Sanango...
Sparked by the publication of large phylogenetic studies and major generic redefinitions in the Gesneriaceae, we review this growing body of molecular studies on the family. Different aspects of molecular data and their use in Gesneriaceae systematics are considered including conceptual challenges on the phylogenetic work undertaken to date as well...
Following recent molecular phylogenetic studies in Old World Gesneriaceae the nomenclatural implications for names in Henckelia are examined. New combinations are made in Codonoboea and Loxocarpus to account for species now excluded from Henckelia. A list is presented in which the current position of all species hitherto assigned to Henckelia is gi...
The Araceae include both taxa with rewarding and deceptive trap pollination systems. Here we report on a genus in which rewarding and imprisonment of the pollinators co-occur. We studied the pollination of four species of Colocasia in Southwest China and investigated the morpho-anatomical adaptations of the spathe related to the attraction and capt...
Background and AimsIn the Lamiales, indeterminate thyrses (made up of axillary cymes) represent a significant inflorescence type. However, it has been largely overlooked that there occur two types of cymes: (1) ordinary cymes, and (2) 'pair-flowered cymes' (PFCs), with a flower pair (terminal and front flower) topping each cyme unit. PFCs are uniqu...
Pollinators have long been known to select for floral traits, but the nature of this relationship has been little investigated in trap pollination systems. We investigated the trapping devices of 15 Arum spp. and compared them with the types of insects trapped. Most species shared a similar general design of trap chamber walls covered in downward-p...
Protogyny is supposed to represent the ancestral form of dichogamy in the angiosperms, but is rare in advanced groups such as the Asteridae, in which protandry prevails by far. Here we report on an unusual form of protogyny combined with herkogamy in a Chinese species of Gesneriaceae (Asteridae–Lamiales): Oreocharis acaulis (formerly Opithandra aca...
A new species of Gesneriaceae, Henckelia pradeepiana, is described from the southern Western Ghats, India. The species is remarkable by the presence of flat tubers, from which shoots with a single or few basal leaves and large and lax inflorescences (pair-flowered cymes) emerge. The corolla is white or pale violet and obliquely campanulate. Also re...
Unlabelled:
Premise of the study:
Floral traps are among the most sophisticated devices that have evolved in angiosperms in the context of pollination, but the evolution of trap pollination has not yet been studied in a phylogenetic context. We aim to determine the evolutionary history of morphological traits that facilitate trap pollination and...
Clusia valerioi Standl. and C. peninsulae Hammel, sp. nov. (formally established in the Appendix), two Central American species of Clusiaceae offering resin as a floral reward, were studied in the Piedras Blancas National Park, SW Costa Rica. Basic data on phenology, flower structure, course of anthesis, flower visitors, flower visitation and polli...
A comprehensive morphological and anatomical analysis was carried out on seeds of all 15 species currently recognized in the genus Nigella s.l. (including Komaroffia and Garidella). In addition, a selection of six infraspecific taxa was examined. Using testa thin sections, morphometry, and SEM imaging, seed coat characters proved to be a highly dia...
The polyphyletic genus Chirita is remodelled after an extensive molecular phylogenetic study of species assigned to it and to other associated genera. Most of Chirita sect. Chirita and the monotypic Hemiboeopsis are amalgamated with Henckelia sect. Henckelia, resulting in a very differently circumscribed genus Henckelia and the synonymisation of Ch...
Based on molecular data and a morphological evaluation, evidence is provided that the species of eleven, mostly small-sized and monotypic genera of Chinese Gesneriaceae (Ancylostemon, Bournea, Briggsia s.str., Dayaoshania, Deinocheilos, Isometrum, Opithandra, Oreocharis, Paraisometrum, Thamnocharis, Tremacron) form a highly-supported group in which...
Based on molecular studies, the small Chinese genus Petrocodon (two species and one variety) has been recently enlarged to include the monotypic genera Calcareoboea, Paralagarosolen and Tengia. It is shown here that the (6-7) species of Lagarosolen, the monotypic Dolicholoma, a few species of Didymocarpus, and a number of new species that have rece...
Based on molecular data and morphology, Metabriggsia is reduced to synonymy with Hemiboea and its two species transferred to that genus.
Based on a considerably enlarged sampling, a phylogenetic analysis of the largest group of didymocarpoid Gesneriaceae, the
“advanced Asiatic and Malesian genera”, was performed, covering all but 3 of the 60 genera presently recognised in this group
(20 of these, mostly from China, are monotypic). The results suggest that no fewer than 17 out of the...
A comprehensive morphological and anatomical analysis was carried out on seeds of all 15 species currently recognized in the genus Nigella s.l. (including Komaroffia and Garidella). In addition, a selection of six infraspecific taxa was examined. Using testa thin sections, morphometry, and SEM imaging, seed coat characters proved to be a highly dia...
A comprehensive morphological and anatomical analysis was carried out on seeds of all 15 species currently recognized in the genus Nigella s.l. (including Komaroffia and Garidella). In addition, a selection of six infraspecific taxa was examined. Using testa thin sections, morphometry, and SEM imaging, seed coat characters proved to be a highly dia...
The phylogenetic placement of the Old World Gesneriaceae genera Ramonda, Conandron, Bournea, Thamnocharis, and Tengia, all characterized by actinomorphic flowers, has been the subject of much debate. Actinomorphy in Gesneriaceae is rare, with most species exhibiting zygomorphic flowers. The actinomorphic genera have historically been considered “pr...
The phylogenetic placement of the Old World Gesneriaceae genera Ramonda, Conandron, Bournea, Thamnocharis, and Tengia, all characterized by actinomorphic flowers, has been the subject of much debate. Actinomorphy in Gesneriaceae is rare, with most species exhibiting zygomorphic flowers. The actinomorphic genera have historically been considered “pr...
A new neotropical genus, , with a single species, , is described from the Cordillera del Cóndor and Amazonian regions of southeastern Ecuador and is placed in the family Gesneriaceae, tribe Beslerieae. The placement of in the tribe Beslerieae is strongly supported by molecular sequence data generated from analyses of nuclear ribosomal DNA internal...
Although the floral morphology of Oleaceae appears to be simple at first sight, fundamental problems still exist. The most detailed morphological studies date back to the 1920s but do not contain developmental data. Such data, based on the SEM investigation of 15 species out of 10 genera and covering most tribes and subtribes of the family, are pre...
The presence of kettle traps in the Araceae is well known. A perfect example is Arum nigrum, which has been paradigmatically studied by Fritz Knoll (1926). However, many aspects of the structure and function of the traps are still poorly known, and, of course, many aroids have no traps or only imperfect traps ('semi-traps'). Araceae thus provide a...
Extreme modification and reduction in floral morphology presents an obstacle to determining the evolutionary relationships and homologies of the holoparasites in Balanophoraceae. Developing flowers and inflorescences of two dioecious species, Balanophora papuana and B. elongata, were compared to each other and to the monoecious B. fungosa. Intermin...
The 'didymocarpoid Gesneriaceae' (traditional subfam. Cyrtandroideae excluding Epithemateae) are the largest group of Old World Gesneriaceae, comprising 85 genera and 1800 species. We attempt to resolve their hitherto poorly understood generic relationships using three molecular markers on 145 species, of which 128 belong to didymocarpoid Gesneriac...
The Golfo Dulce region is botanically one of the most diverse areas in Central America. During the last 15 years, research plots have been established in the Piedras Blancas National Park and its surroundings, for the investigation of species composition, vegetation structure, growth patterns, reproductive ecology and forest dynamics. This paper pr...
Whereas seed features of Scrophulariaceae (in their traditional circumscription) have been well studied and used as a taxonomic marker, little attention has been paid to how the seeds are attached to the placenta. The structures supporting the seeds are usually referred to as seed funicles, but study of development shows that they develop from the...
The present paper is part of a study dealing with various aspects of reproduction of two Costa Rican Clusia species offering resin as a floral reward. It provides data on the floral development and flower (especially stamen and staminode) anatomy of one of the species, Clusia valerioi. In the early stages, both male and female flowers develop in th...
The recent establishment of the new family Calceolariaceae, separated from Scrophulariaceae on the basis of molecular evidence, is complemented here by a scanning electron microscopy study of floral morphology and development of 12 species encompassing all genera (Calceolaria, Jovellana, and Stemotria [= Porodittia]). All species showed a similar p...
The number of tribes recognised in Old World Gesneriaceae has
steadily decreased, numbering presently four. Molecular studies
continue this trend: only two major clades can be sharply
delimited: (I) the small clade of Epithematoid Gesneriaceae, (II) the
large clade of Didymocarpoid Gesneriaceae. While in the former
the relationships of the six...
Exorhopala ruficeps is a rare parasitic plant of the family Balanophoraceae, endemic to the north-western part of Peninsular Malaysia. It was originally described in Rhopalocnemis and later placed in a new monotypic genus on the basis of the exogenous origin of its inflorescences. A new collection of material enabled a detailed morphological study,...
Weber, Anton (Institute of Botany, University of Vienna, Rennweg 14, A-1030 Vienna, Austria) 2004. Gesneriaceae and Scrophulariaceae: Robert Brown and now. Telopea 10(2): 543-571. Though Robert Brown seems to have seen only one or two species of Gesneriaceae in the field, he understood the family admirably well and had an everlasting influence on i...
Perennial or rarely annual herbs, subshrubs, shrubs or rarely small trees; perennial herbs with fibrous roots or with rooting above- or underground stems, rootstocks, rhizomes, scaly rhizomes, or tubers; terrestrial, epiphytic or climbing. Stem erect, ascending, decumbent, creeping, pendulous, or ± absent. Leaves opposite, sometimes in whorls of th...
The systematic position and generic differentiation of the morphologically and geographically outstanding tribe Epithemateae (Gesneriaceae) was analyzed using the rbcL/atpB-spacer and trnL-F intron-spacer regions of chloroplast DNA. In our analysis Epithemateae forms a strongly supported monophyletic clade (bootstrap [BS] = 100%; jackknife [JK] = 1...
The paper reviews briefly the presently available information on bee-flies (Bombylius, Bombyliidae, Diptera) and their role in the pollination of flowers. It combines literature data and the results of field studies carried out over three consecutive flowering seasons in the surroundings of Vienna (Lower Austria). Field work concentrated on factors...
Zusammenfassung Als Grundlage für eine zukünftige Revision von Didymocarpus WALL, (im emendierten Umfang von WEBER & BURTT 1998) wird eine Liste der Sektionen und der relevanten Arten (einschließlich infraspezi-fischer Taxa, nomina nuda und illegitimer Namen) präsentiert. Die Information zu den einzelnen Arten umfaßt das Zitat der Originalpublikati...
The film (WEBER 1992) demonstrates and explains the elaborate flower structure of Nigella arvensis in relation to pollination. The course of anthesis (stamen and style movements in the male and female stage) is shown in rapid motion. Of special interest is the unique mode of anther dehiscence and pollen presentation. Pollination by various hymenopt...
Structure, dynamics and pollination of the flower of Nigella arvensis (Ranunculaceae) A comprehensive description of the flower structure, floral dynamics (movements of the stamens and styles) and pollination of Nigella arvensis is presented. New observations refer, inter alias, to the anther dehiscence and pollen presentation, the complex structur...
Crabbea veilutina and Dicliptera laxata exhibit a highly complex and complicated inflorescence organization in which sectorial anisoclady plays an essential role. The capitule-Iike axillary inflorescences of Crabbea are interpreted as indeterminate thyrses, in which all axes are merged into a flat receptacle (coenosome). Due to extreme anisoclady t...
Based on personal collections ofGlobba unifolia
Ridl. andG. unifolia var.sessiliflora
Holtt., the latter is recognized as a distinct species. As the nameG. sessiliflora is already occupied, the nomen novumG. corneri is proposed in honour of Prof. DrE. J. H. Corner, who was the first collector of the plant.
Didymocarpus geitleri spec. nov. is described from Sungai Pandan, Kuantan distr., Pahang, Peninsular Malaysia. Distinctive features include: leaden-grey leaves with long, erect hairs on the upper side and whitish, campanulate flowers with a long exserted, bright yellow style. The colouring of the latter is caused by densely arranged glands. Togethe...
Phyllagathis tuberculata
King and two closely allied new species,P. magnifica
A. Weber andP. stonei
A. Weber, are described and illustrated. Within the genus, these species form a distinct and isolated group which is restricted to Peninsular Malaysia.P. tuberculata occurs in Perak (probably confined to G. Bujang Melaka),P. magnifica andP. stonei ar...
The reproductive structures ofDeplanchea tetraphylla (Bignoniaceae) exhibit a significant number of unusual features: inflorescence with an apical “platform”; flowers yellow, short-tubed, strongly zygomorphic; mouth closed through lateral compression; stamens and style long-exserted, erect or slightly reclined; nectar dark brown, exposed in the spo...
The two characters used byBurtt (1974) to segregate the genusSchizoboea fromDidymocarpus, viz. terminal inflorescence and fruit splitting into 4 valves, have been studied in detail: (a) The terminal inflorescence represents a bracteate florescence (sensuTroll), that is an open thyrse, peculiar because of its only two extremely condensed internodes...
Nicolaia elatior is used as an example to demonstrate that the “mucronate” tepals ofZingiberaceae correspond to hypsophylls (bracts) consisting of a leaf sheath and a rudimentary “Oberblatt” (= leaf petiole + lamina) represented by the “mucro”. Evidence for this interpretation is furnished by all available criteria: leaf sequence (exhibiting a comp...
A new interpretation of the shoot and inflorescence structure of the two markedly anisophyllous genera Loxonia and Stauranthera is presented.
Within the genusLoxonia
Jack, currently regarded as monotypic, three species are recognized:L. hirsuta
Jack (Sumatra, Mentawai-Islands, Java, Borneo, Anambas-Islands, Malay Peninsula),L. discolor
Jack (Sumatra) andL. burttiana
A. Weber, spec. nova (Borneo). [Key with English translation p. 203.] There is evidence thatL. discolor is the most primiti...
The MediterraneanOrobanche variegata has n = 38. This is the third tetraploid taxon known from sect.Orobanche.
Rhabdodendron macrophyllum (Spruce ex Benth.)Huber andR. amazonicum (Spruce exBenth.)Huber differ in several anatomical and morphological characters (secretory cavities, hypoderm, peltate hairs, internodal region and petiole). A position of the monotypicRhabdodendronaceae in theCentrospermae as recently suggested is hardly supported: Peltate hairs,...
The shoot organization and inflorescence structure ofEpithema is analyzed. On the main axis micro- and macrocotyledon (the latter falling off early) are followed by a long epicotyl, then a large, solitary leaf (B3) and above this a dimerous leaf whorl (B4, B5). The last internode of the main axis is the basic internode of the main florescence (Trol...
The chromosome numbers of five species ofOrobanche sect.Orobanche (O. alsatica, O. laserpitii-sileris, O. loricata, O. salviae, O. teucrii) are reported for the first time and previous counts could be verified in ten other species. Now the chromosome numbers of all species of sect.Orobanche occurring in Central Europe are known: they are diploid (2...
The thickened shoot bases ofNeoalsomitra podagrica carry spines of an undescribed nature: they represent morphologically phyllodes. A closed ring of sclerenchyma originating from the fusion of vascular bundle sheaths is responsible for the rigidity of these organs. Contrary to their cylindric structure these phyllodes are to be considered as bifaci...
InOrobanche gracilis
Sm. (collected in Vienna, Lower Austria, and N. Italy) the somatic chromosome numbers were found to be inter-and intra-individually variable. Most plants yielded counts of around the tetraploid level (2n = 73–91), a few of around the hexaploid level (2n = 112–116). Only 36% of the plants were eusomatic, only 24% eutetraploid (2...
The foliar appendages at the base of the short petiole in some taxa ofRhytidophyllum are often called “stipules”. But this term is not applicable, because these appendages lack important characteristics of true stipules, f. i. constancy in form and appearence during leaf succession, early ontogenetic origin and prolepsis. Nevertheless they are effi...
Cruciferae are commonly said to have no stipules, but some authors have correctly pointed out that tiny stipules are nearly always present and form a regular morphological component of the leaf structure in this family (cf.Weberling, 1956).
The present investigations refer to the stipules and the morphology of the storage scales on the rhizomes inD...
The genus Didymocarpus has for long been used as a dumping ground for species of different affinities and different geographical origin. Following recent work on Didymocarpus and the associated genera Loxo- carpus, Codonoboea, and Platyadenia, which resulted in a much narrower delimitation of Didymocarpus, the re-instatement and enormous expansion...
Schon FRITSCH (1893, 1904) und GOEBEL (1898) haben erkannt, daß sich die zweizeilige Beblätterung von Rhynchoglossum (inkl. Kluftia) von eine_r_a_nisophy-l-l-virerz~eiTigen ableitet, wie-sie b~el~~Loxonia in typischer Ausprägung gegeben ist, näm- lich inden die Minus-Blätter vollständig abortieren (Näheres vgl. WEBER 1978). Sonstige morphologische...
Pentaphragma is a peculiar genus of Malesian rain forest herbs, which was formerly often included in Campanulaceae, but is now generally regarded to represent a family of its own. Recent molecular-systematic and morphological-cladistic studies (LAMMERS 1992; COSNER et al. 1994; GUSTAFSSON & BREMER 1996) have confirmed that the family has its place...
Auf Grund von Geländestudien während dreier Vegetationsperioden im Wiener Raum sowie der Auswertung von Literaturdaten wurde versucht, die Rolle der Wollschweber als Bestäuber von Blüten zu evaluieren. Im Gelände wurden Frequenzzählungen von Blutenbesuchen zu verschiedenen Zeiten der Vegetationsperiode bzw. Flugzeiten der Wollschweber (Mitte März b...
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The La Gamba Field Station is a research and teaching facility of the University of Vienna, situated at the edge of the Piedras Blancas National Park in SW Costa Rica. Being located in one of the most species-rich lowland rainforests in Central America, it is an ideal location for field research, courses and seminars. The field station plays a significant role in research into tropical rainforests, raises awareness for rainforest conservation and research, and provides an opportunity for students and anyone interested in the natural world to increase their knowledge of rainforests.