Paleobotanical studies inFagaceae of the European Tertiary

A systematic reassessment of megafossil records ofFagaceae in Central Europe has been undertaken on the basis of leaf cuticular characters. The oldest representatives date back to the Eocene:Quercus subhercynica spec. nova,Dryophyllum furcinerve (Rossm.)Schmalh.,Trigonobalanopsis rhamnoides (Rossm.) gen. & comb. nov. In the Oligocene other members of extant genera appear:Quercus rhenana (Weyl. & Kilpp.)Knobloch & Kvaek,Fagus attenuata Goepp.,Lithocarpus saxonicus spec. nova. In the Neogene these ancient taxa (except inFagus lineage), are gradually replaced by deciduous species ofQuercus andCastanea. Trigonobalanus andCastanopsis are recorded by fruits (or wood) only.     

Three new species and a new combination in the genusTorulomyces from soil

Seven isolates ofTorulomyces from Asian and Australian soil samples were studied in comparison with known taxa of the genus and withMonocillium indicum, the type species ofMonocillium. Three new species,Torulomyces parviverrucosus, T. laevis, andT. ovatus, are described, andT. brunneus is described as a new combination. Conidial characteristics, especially their shape and surface structure, are useful taxonomic criteria for distinguishing species ofTorulomyces. Monocillium is considered to be a distinct genus.     

Systematics of AustralianLepidium species (Brassicaceae) and implications for their origin: Evidence from IEF analysis of Rubisco

Variation in subunit polypeptide composition of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) from native AustralianLepidium taxa was analyzed by isoelectric focusing (IEF). Species of grexMonoplocoidea on the one hand, and species of gregesPseudoruderalia andPapillosa on the other, were well separated by Rubisco IEF patterns. The protein data suggest grexMonoplocoidea to be placed in sect.Monoploca whereas gregesPseudoruderalia andPapillosa should be integrated into sect.Dileptium. We suggest that the Rubisco type of American and/or AsianLepidium species was contained in those plants migrating to Australia and evolving into the recent native Australian species. Fossil pollen records and vegetation history indicate that the origin ofLepidium in Australia was restricted to the late Tertiary of Quaternary. Data presented in this study fit best with an immigration by long-distance dispersal of seeds by birds from Asia and/or from South America.     

Anatomical changes and evolutionary trends in the foliar epidermis of extant and fossil Euro-Mediterranean oaks (Fagaceae)

The differentiation of foliar epidermis structures, cuticles, stomata, and indumentum of most of the extant Euro-Mediterranean taxa ofQuercus have been studied by light and scanning electron microscopy, and compared with other genera and fossil material. Results allow the recognition of the subgg.Sclerophyllodrys, Cerris andQuercus, and of various sections and even individual species. The cyclocytic stomata type, regarded as plesiomorphic, is found in the geologically oldest representatives of the familiy (Dryophyllum, resp.Eotrigonobalanus) and in the relatively old, evergreen to semi-evergreen species ofQuercus subgg.Sclerophyllodrys andCerris. These taxa also have relatively thick and smooth cuticles. Anomocytic stomata, thinner cuticles and the presence of crystalline wax flakes are regarded as apomorphic features and characterize the deciduous taxa of subg.Quercus. These changes are interpreted as ecological adaptations to the changing climates from the Tertiary to the present. An analysis of the various character combinations found in macrofossils and the often poor species separation inQuercus suggest that hybridization has played a major role in the evolution of the Euro-Mediterranean oaks.     

History of the montane forests of the northern Andes

From the vascular plant genera of the tropical Andean montane forests about 65% have a tropical-neotropical, 15% tropical-Andean, 5% amphi-pacific (Malayo-American), 5% Austral-antarctic and 10% Holarctic distribution. The explosive evolution of Andean centred taxa probably started in the lower Tertiary from tropical Gondwana stock, when in the area of the present day Andes, locally there may have been hills up to 1 000m. With the final upheaval between the Late Miocene and Late Pliocene, extensive areas with a montane climate were created and populated from the low mountain flora by evolutionary radiation. Taxa of Austral-antarctic origin migrated along the Andean chain to the tropics. At the same time the formation of the Panama isthmus connected N. and S. America, and enabled many plants to enter the tropical Andes from the north. First to cross were tropical to subtropical and warm-temperate species from the Tertiary Laurasian flora that had migrated southward during the period of Miocene cooling, taking refuge in the montane tropics. Because the same happened in SE. Asia there is a good number of amphi-pacific taxa known as fossils from Tertiary Laurasia but largely extinct in the present-day Holarctic (e.g.,Trigonobalanus). Later to cross were cool-temperate to cold elements that still exist in the Holarctic (e.g.,Alnus andQuercus).     

History and biogeography of the mangrove ecosystem,based on a critical reassessment of the paleontological record

The geological record of mangrove plants is based on comparablemorphological characteristics of pollen, fruits and wood, of fossil andmodern species. But this record relies on the assumption that the ecologicaland habitat preferences of ancestral taxa have remained similar throughages. A reexamination of fossil evidence of Avicennia, Pelliciera,Sonneratia, Rhizophora, Bruguiera, Ceriops, etc.reveals that the modern mangrove flora was pantropic by the Eocene, andappears to have originated during Paleocene times. Earlier Paleozoic andMesozoic candidates for a mangrove ecology lack conclusive evidence oftheir exclusive association with tidal environments. It is therefore clear thatcontinental drift had a limited role in the dispersal and development ofmodern mangrove floras. The Eocene/Oligocene boundary crisis appears toherald a beginning of the biogeographic split between the current-dayeastern and western provinces of mangrove plants. But, while the climaticorigins of this major disjunction is not clearly understood, our reassessmentof Tertiary paleoclimates suggests that the major cooling events of themiddle Paleocene, the end of the Eocene and the middle Pliocene were themost likely influences on the evolution of mangrove floras. The associatedinvertebrates, especially molluscs, further support our assertion that amodern mangrove ecosystem was established only during the earliestEocene times. We summarize our interpretation in a set of 9 palinspasticmaps of fossil mangrove genera through their evolution ending with thecurrent, bipartite distribution of present day taxa.     

Model of a hypothetical protohominid dentition and its implications for hominid phylogeny

The complete dentition of the common ancestor ofAustralopithecus andHomo, intermediate between that of a pongid and a hominid, is virtually unknown. The maxillary dentition (P3-M2) ofRamapithecus brevirostris Lewis, 1934, a pongid from the Early Pliocene, and that of hominids from the Late Pliocene and Plio/Pleistocene is known. SinceR. brevirostris is probably ancestral to the hominids, a model of intermediate maxillary dentition (P3-M2) is extrapolated and described. The model represents a hypothetical protohominid dentition. It does not conform with the teeth ofAustralopithecus, but shows greater morphological affinity to hominine dentition and to 5 myo hominids. TheHomo lineage, therefore, may go back to the Middle Pliocene. According to the normal sequence of evolution, it is most unlikely thatAustralopithecus gave rise toHomo, but much more probable that a very early, generalizedHomo evolved into an advanced, specializedAustralopithecus.     

A new point of view on the taxonomy ofPottia starckeana agg. (Musci,Pottiaceae)

A new taxonomic treatment is proposed for thePottia starckeana species complex. The peristome development is not considered to be a useful feature to separate the taxa. On the basis of spore morphology only two species are accepted:P. starckeana, with spores wavy in outline, andP. davalliana, with variously-shaped and developed processes on the spores.Pottia starckeana var.brachyoda is reduced to synonymy withP. starckeana; P. conica andP. commutata are treated as synonyms ofP. davalliana. The speciesP. mutica, P. affinis, P. salina, P. microphylla, P. texana, andP. arizonica (included var.mucronulata) are considered taxa of doubtful affinity, as they have spore features intermediate between the two spore types established for the group. The identity ofP. appertii andP. recurvifolia has not been elucidated because the type material has been destroyed.     

Phylogenetic relationships in the genusStylosanthes (Leguminosae) based upon chloroplast DNA variation

A detailed analysis of chloroplast DNA restriction fragment length variation was undertaken to reconstruct the maternal phylogeny of 18 taxa from both sections of the papilionoid tropical forage legume genusStylosanthes. Data were analysed by means of the computer program PAUP, using an heuristic search with Wagner parsimony. The resulting cladogram dividedStylosanthes into four separate clades, which comprised: (i) theS. guianensis complex and related species (i.e.S. gracilis, S. grandifolia andS. montevidensis); (ii)S. hispida, tetraploidS. hamata s. l.,S. sympodialis, S. humilis, S. leiocarpa, S. angustifolia and certain accesions ofS. scabra; (iii)S. calcicola, S. viscosa, diploidS. hamata s. str., andS. fruticosa, plus accessions ofS. scabra, S. capitata and one accession ofS. grandifolia; and (iv)S. macrocephala and other accessions ofS. capitata not included within clade 3. Results are generally congruent with previously established interspecific relationships and, moreover, enabled identification of putative maternal progenitors for four tetraploid taxa:S. humilis was identified as a likely maternal parent of bothS. sympodialis andS. hamata s. l.,S. viscosa as a maternal parent ofS. scabra, andS. macrocephala as a maternal parent ofS. capitata.     

The mangrove palm Nypa in the geologic past of the New World

The paleontological history of Nypa, known today as the mangrovepalm, is traced through geological time back to the Late Cretaceous. Emphasis is laid on the New World occurrences, especially in NorthAmerica, where Nypa is known from fossil fruits and pollen. In SouthAmerica, the stratigraphic range of this palm extends from theMaastrichtian to the late Eocene, whereas in North America, Nypa isrestricted to only the Eocene. Nypa occurs as pollen all along theAmerican Gulf Coast from the early Eocene (Ypresian) to the late Eocene(Priabonian), while fruit records come from the early and middle Eoceneof Maryland and Texas, respectively. The floristics of these Eocenemangroves, including possible mangrove associates, and the developmentof mangrove vegetation in the neotropics through the Tertiary andQuaternary, are discussed. New paleobotanical evidence from a middleEocene faunal and floral assemblage in Texas, the Casa Blanca flora (LaredoFormation, Claiborne Group), which contains fossil Nypa pollen andfruits, is described in detail.     

rbcL sequences support exclusion ofRetzia,Desfontainia, andNicodemia from theGentianales

The taxonomic positions ofRetzia, Desfontainia, andNicodemia have been much discussed, and all three genera have been included inLoganiaceae (Gentianales). We have made a cladistic analysis ofrbcL gene sequences to determine the relationships of these taxa toGentianales. Four newrbcL sequences are presented; i.e., ofRetzia, Desfontainia, Diervilla (Caprifoliaceae), andEuthystachys (Stilbaceae). Our results show thatRetzia, Desfontainia, andNicodemia are not closely related toLoganiaceae or theGentianales. Retzia is most closely related toEuthystachys and is better included inStilbaceae. The positions ofDesfontainia andNicodemia are not settled, butDesfontainia shows affinity for theDipsacales s.l. andNicodemia for theLamiales s.l.     

The phylogeny ofPapaver s. l. (Papaveraceae): Polyphyly or monophyly?

An RFLP analysis of the chloroplast genetrnK of 32 species of the generaPapaver, Roemeria, Stylomecon, andMeconopsis leads to the following conclusions: (1) AsianMeconopsis consists of two distinct clades and is paraphyletic in relation toPapaver, Roemeria, Stylomecon, and the W EuropeanMeconopsis cambrica. (2) Sister group relationships ofRoemeria toPapaver sect.Argemonidium and ofStylomecon toPapaver californicum are well-supported. (3)Meconopsis cambrica is nested withinPapaver (incl.Roemeria andStylomecon). The consideration of morphology, geographical distribution and ecology leads to the conclusion thatM. cambrica is best regarded as a member ofMeconopsis, and thatPapaver arose polyphyletically from within a paraphyleticMeconopsis in response to Tertiary climatic aridification. — The removal ofM. cambrica from the taxon matrix is discussed. It is concluded that this experiment illuminates the importance of critical taxon sampling, and shows that at least potentially the assessment of taxa as mono-, para-, or polyphyletic may characterize their present status only and need not reflect their phylogenetic history.     

Phylogeny ofRubiaceae-Rubieae inferred from the sequence of a cpDNA intergene region

A phylogenetic analysis of 25 species, representing eight genera of theRubieae tribe (Rubiaceae), has been made using the DNA sequence of the chloroplastatp B-rbc L intergene region. Six tropical genera from other tribes ofRubiaceae have been used as outgroups. Whatever the method of analysis (distance, parsimony or maximum likelihood), five groups are clearly separated and described as informal clades. Their relative relationships are not clearly resolved by the parsimony analysis, resulting in eight equally parsimonious trees, 327 steps long, with a consistency index (CI) of 0.749 (excluding uninformative sites). TheRubieae tribe appears monophyletic from the data available. Some new and partly unexpected phylogenetic relationships are suggested. The genusRubia forms a separate clade and appears to be the relatively advanced sister group of the remaining taxa. TheSherardia clade also includes the generaCrucianella andPhuopsis. Galium sect.Aparinoides appears closely attached to theAsperula sect.Glabella clade. The remaining taxa ofGalium are paraphyletic:Galium sect.Platygalium (in theCruciata clade) is linked to the advanced generaCruciata andValantia; the more apomorphic groups ofGalium form theGalium sect.Galium clade, including the perennial sectionsGalium, Leiogalium, andLeptogalium as well as the annual (and possibly polyphyletic) sect.Kolgyda.     

ITS sequences from nuclear rDNA suggest unexpected phylogenetic relationships between Euro-Mediterranean, East Asiatic and North American taxa ofQuercus (Fagaceae)

Nucleotide sequences from the internal transcribed spacer (ITS) regions of the 18S–26S nuclear ribosomal DNA have been studied from ten species ofQuercus (representing four subgenera),Castanea sativa andFagus sylvatica, as a preliminary molecular contribution to the still poorly understood systematics and evolution ofFagaceae. The resulting matrix has been used to calculate pair-wise sequence divergence indices and to construct a maximum parsimony tree forQuercus coding indels as a fifth state. Divergence is greater forQuercus vs.Fagus than forQuercus vs.Castanea. The tree for theQuercus taxa studied reveals two clearly divergent clades. In clade I the evergreen W MediterraneanQ. suber appears in a basal position as sister to more distal deciduous taxa, i.e. the E MediterraneanQ. macrolepis and the E AsiaticQ. acutissima (all formerly united as different sections under the apparently polyphyletic subg.Cerris), andQ. rubra (a representative of the N American subg.Erythrobalanus), forming a pair withQ. acutissima. In clade II the evergreen southeastern N AmericanQ. virginiana is basal and sister to the remaining three branches, i.e. a pair of evergreen Mediterranean taxa withQ. ilex andQ. coccifera (subg.Sclerophyllodrys), the deciduous but otherwise plesiomorphic SE European/SW AsiaticQ. cerris (type species of subg.Cerris), and the related but more apomorphic European pairQ. petraea andQ. robur (subg.Quercus). These results partly conflict with current taxonomic classification but are supported by some anatomical and morphological characters. They document polyphyletic lines from evergreen to deciduous taxa and suggest Tertiary transcontinental connections within the genus.     

Genotypic variation in progeny of the agamic grass complexPennisetum sectionBrevivalvula in West Africa

The genotypic variation of 1180 progeny from 118 genitors belonging to five taxa ofPennisetum sect.Brevivalvula has been estimated by isoenzyme electrophoresis with observations on five enzymatic systems, in order to compare the type of reproduction in polyploid and diploid taxa. A total of 112 different isozyme genotypes has been found, over all taxa. Genotypic variation was found among all progeny of the diploid populations ofP. polystachion andP. subangustum, as a consequence of their sexual reproduction system. At the polyploid level the type of reproduction appears to be predominantly agamic, but genotypic variation in the progeny was not rare: five tetraploid and one hexaploidP. pedicellatum, one pentaploid and one hexaploidP. polystachion and one hexaploidP. hordeoides, in a total of 90 genitors. Genetic relationships have been observed between the diploid sexualP. polystachion andP. subangustum, and, to a lesser extent, with the tetraploids of the same taxa as well. TetraploidP. polystachion andP. pedicellatum share genotypes with most other chromosomal taxa.     

Hybridisation,genomic constitution and generic delimitation inElymus s. l. (Poaceae: Triticeae)

Intergeneric crosses were made between representatives of the genomically-defined generaElymus, Agropyron, Elytrigia, Pseudoroegneria, andThinopyrum. The genomic constitution ofElytrigia repens, the type species ofElytrigia, is shown to be SSH, a genomic combination otherwise found only inElymus. The S genome ofPseudoroegneria has almost always a dominant influence on the morphology of the taxa of which it is a component.Wang (1989) showed that the J genome inThinopyrum and the S genome have considerable homoeology, with a mean c-value of 0.35 in diploid SJ hybrids. A genetic coherence from S to SJ^e, J^e, J^eJ^b, and J^b can be expected, agreeing with the continuous morphologic variation pattern observed. Because of the absence of morphological discontinuities between the taxa,Pseudoroegneria (S),Elymus (SH, SY, sometimes with additional genomes),Elytrigia (SSH, SSHX), andThinopyrum (SJ, SJJ, J) are best treated as a single genus,Elymus, following the generic concept ofMelderis in Flora Europaea and Flora of Turkey. The basic genomic constituents ofElymus will then be the S and/or J genomes.Agropyron, with diploids, tetraploids, and hexaploids based on the P genome is morphologically distinct from other genera inTriticeae. In a few species ofElymus andPseudoroegneria, a P genome is an additional constituent. In these cases the P genome has a negligible morphological influence. Therefore, it seems reasonable to maintainAgropyron as a separate genus.     

Floral evolution and phylogeny in the tribeThelymitreae (Orchidaceae: Neottioideae)

The Australian orchid tribeThelymitreae, composed ofCalochilus, Epiblema, andThelymitra, is unique in theOrchidaceae because of the presence of a mitra or staminodal complex. Evidence from floral structure suggests thatEpiblema andThelymitra are sister genera and thatCalochilus is derived from aThelymitra ancestor. A Gene Pool Vortex model and a hypothetical phylogeny illustrate that introgressive hybridization, allopatry, and long distance dispersal have played a major role in the evolution of the tribe. Pollination and hybridization in the tribe are discussed with major emphasis on floral mimicry.     

Nutritional physiology of type isolates of currently accepted species ofExophiala andPhaeococcomyces

Nutritional physiological and tolerance tests were performed for all type strains of species currently classified in the black yeast generaExophiala andPhaeococcomyces, including some additional type strains of taxa recently reidentified asExophiala species. Most describedExophiala species can be distinguished by physiological characters.Exophiala jeanselmei with its varieties, andE. castellanii should all be retained as separate taxa. The pairs of strainsMycotorula schawii/Exophiala dermatitidis, Hormodendrum negronii/Exophiala jeanselmei var.lecaniicorni andSporotrichum gougerotii/Torula bergeri were found to be conspecific. Phenetic analyses of physiological data support the identity ofPhaeococcomyces exophialae as a yeast-like synanamorph ofExophiala spinifera. The taxonomic positions of the generaNadsoniella, Phaeoannellomyces andWangiella are discussed. The generaExophiala andPhaeococcomyces are unrelated.     

New and noteworthyHabenaria spp. (Orchidaceae) from New Guinea and adjacent islands

5 new taxa ofHabenaria, namelyH. bougainvillae, H. elongata R. Br. var.leptophylla, H. ensigera, H. rechingeri andH. trichoglossa, are described and illustrated, with reference to affinities to related Australian and Indo-malayan species. The occurrence in New Guinea of severalHabenaria spp. typical for a savanna-like vegetation, led to look more thoroughly at these taxa:H. elongata R. Br. andH. ochroleuca R. Br., considered so far to be endemic in Northern Australia, andH. khasiana Hook. f., hitherto only known from southeastern Asia.Studies in the subtribeHabenariinae Bentham (Orchidaceae), 2.—Part 1: Candollea34, 357 (1979).Dedicated to Hofrat Prof. DrKarl Heinz Rechinger on the occasion of his 80th birthday. — On April 30, in the year 1927, the author and his brotherOtto Renz metKarl Heinz Rechinger on a small steam-boat in a stormy Aegaen Sea, travelling from Piraeus to the Northern Sporades Islands:Karl Heinz with destination to Chelidromia, the author andO. Renz to Skopelos. By this lucky chance a lasting friendship began.     

Phylogenetic relationships in theCampanulales based onrbcL sequences

Phylogenetic relationships within the angiosperm orderCampanulales were investigated by comparative sequencing of the chloroplast generbcL. CompleterbcL sequences were obtained for ten species in six families within the order. These data were analyzed along with previously publishedrbcL sequences from other taxa (for a total of 117 species) within the subclassAsteridae and outgroups, producing 32 equally parsimonious trees. A subset consisting of 44 of these taxa was then chosen and more rigorous analyses performed, resulting in four equally parsimonious trees. Results indicate that two major clades roughly corresponding to traditionally circumscribedAsterales andCampanulales exist as sister taxa. In particular, therbcL trees indicate thatSphenoclea is not a member ofCampanulales orAsterales, thatPentaphragma is more closely allied toAsterales thanCampanulales, that theCyphiaceae are not monophyletic, thatCampanulaceae andLobeliaceae are not sister taxa, and thatStylidiaceae are correctly placed withinCampanulales.