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Impatiens msisimwanensis S.B. Janssens and E.B. Knox is described as a new species from the Udzungwa Mountains in Tanzania. A comparative morphological study illustrates the affinity between the newly discovered species, I. nana and I. sylvicola . Using a molecular approach we assessed the phylogenetic position of I. msisimwanensis among the East African Impatiens species, thereby confirming its status as a new species. In addition, the pollen morphology of I. msisimwanensis was thoroughly examined.

Pollen and orbicule morphology of 84 species, representing 52 genera from all tribes and subfamilies are investigated, in order to assess the systematic value of palynological data and to determine palynological evolutionary trends in Cyperaceae. A total of 90% of the species are examined for the first time with scanning electron microscopy. Pollen grains of Cyperaceae are oblate spheroidal to perprolate in shape, inaperturate to polyporate with opercula or pontopercula on pori or colpi. We distinguished seven different sexine ornamentation patterns. Orbicules occur in all species investigated. Pollen morphological variation within Cyperaceae is considerable and includes dispersal unit; number, location and degree of differentiation of apertural zones; and sexine ornamentation patterns. In subfamily Mapanioideae both tribes can be characterized by palynological synapomorphies. However, in subfamily Cyperoideae, the observed pattern of variation does not fit the most recent molecular phylogeny due to high levels of homoplasy and polymorphism in major pollen characters.

Aim To study the present-day olive stands and their ecology in the eastern part of the territory of the ancient city of Sagalassos, to study the variation of olive pollen production and dispersal near the olive stands, to establish a modern pollen reference model, and to compare Hellenistic–Roman pollen data from two wetlands with this modern reference model. Location Eastern part of the territory of the ancient city of Sagalassos, western Taurus mountain range in south-west Turkey. Methods The study is based on field survey, pollen analysis of surface samples, multivariate statistics of modern pollen data and the use of ‘modern analogues’ in comparison with Hellenistic–Roman pollen samples. Results A field survey revealed the presence of 35 olive stands in the study area. These are mainly small-scale stands. The olive pollen representation in the surface samples is highly variable. Two groups of modern ‘olive’ pollen spectra could be distinguished: (1) a group representing mainly olive stands from lush and moist mixed orchards; and (2) a group representing mainly olive stands from open small-scale olive stands in combination with annual crop agriculture. Although no ‘perfect’ modern analogue was found for the Hellenistic–Roman pollen data, the fossil pollen data show similarities with modern spectra from the second group, due to the presence of relatively high pollen values for secondary anthropogenic indicators. Main conclusion A well-organized and diverse, but time- and energy-consuming, agricultural system was maintained nearby the wetlands of Canakli soils, presumably to maximize the yields in both valleys.

Background: In the locules of anthers of flowering plants, tiny (1.5-2 µm) granules of sporopollenin may occur next to the pollen grains. Those granules, called orbicules, mostly occur on the radial and innermost tangential wall of secretory tapetum cells. Methods: We have investigated the presence of orbicules in 15 important European allergenic species with scanning electron microscopy (SEM). Results: Orbicules were present in all species investigated of the families Betulaceae, Chenopodiaceae, Fagaceae, Poaceae, Polygonaceae, and Urticaceae. However, in the Asteraceae and Oleaceae species studied, orbicules were lacking. In all Chenopodiaceae, Poaceae, and Urticaceae species, orbicules were attached to the pollen exine. These observations indicate the possibility of the dispersal of orbicules into the atmosphere during anthesis. Conclusions: The hypothesis of the potential role of orbicules as possible important vectors of allergens is put forward, based on the comparison of our results with recent literature about the evidence of allergenic activity in the smaller micronic atmospheric aerosol fraction. Our results provide evidence that an in-depth investigation of the sites of allergens across the whole anther is required. We suggest that allergen researchers apply immunoelectron microscopy on whole anthers to determine whether orbicules possess allergens.

Sixteen species of 14 genera of 7 different tribes of the Cinchonoideae (Rubiaceae) were investigated with a scanning electron microscope to examine orbicule presence and morphological diversity. Orbicules are lacking only in Gouldia terminalis (Hook, et Arn.) Hbd. and Simira rubescens (Benth.) Bremek. ex Steyerm. Four orbicule types could be distinguished mainly on the basis of shape and ornamentation characteristics. Spiny orbicules (type I) we found only in the Catesbaeeae (sensu Delprete). Augusta longifolia (Spreng.) Rehd. has microrugulate orbicules (type II). Smooth and spherical orbicules smaller than 0.5 μm (type III) are most widespread in our sample of the Cinchonoideae. In Burttdavya nyasica Hoyle, they are irregular and folded (type IV). For each species a description is given of the orbicule and of the sexine morphology, to allow comparison. Species with spiny orbicules always have microspines on the pollen sexine. For the other orbicule types no such resemblance could be observed. Transmission electron microscope observations of four species are included to comment on ultrastructural differences between orbicule types. From this preliminary survey, we suggest that orbicule features in Cinchonoideae may be systematically useful on generic and tribal levels. Key words: Ubisch bodies, Rubiaceae, Cinchonoideae, orbicule ultrastructure, tapetum.

The possible alliance between Gaertnera and Pagamea (Rubiaceae-Rubioideae), two genera from the Old and New World, respectively, is investigated on the basis of wood anatomy and pollen morphology. Nowadays, the main point of discussion about the taxonomic position of these genera is whether they belong to the Psychotrieae or constitute a tribe Gaertnereae characterised by their secondarily superior ovary and sheathing stipules. Both the wood and pollen of the genus pair are found to show specific features absent in other genera of the Psychotrieae, e.g. parenchyma bands in the xylem and endexine thickenings on the polar sites of the pollen apertures. Nevertheless Gaertnera and Pagamea share many other characters with the Psychotrieae. Wood and pollen convincingly demonstrate the very close affinity of the two genera. The sister pair differs in so many features from other Psychotrieae, that Gaertnera and Pagamea should constitute at least a subtribe Gaertnerinae, formally recognized here. The general lack of profound studies on the affinities within the very large tribe Psychotrieae makes further comments on the taxonomic relationships of the Gaertnerinae difficult.

This study examines the diversity and character transformations in pollen and orbicule morphology of Ebenaceae, with a focus on subfamily Ebenoideae (ca. 600 sp.). 62 specimens comprising all three genera of Ebenoideae (Diospyos, Euclea, Royena), were studied using LM and SEM. Bayesian phylogenetic analysis was performed on molecular sequence data to establish an evolutionary hypothesis that was then used as an evolutionary framework to identify synapomorphies and trace evolutionary trends of palynological data with Bayesian posterior mapping and principle component analyses (PCA). Ebenoideae pollen is generally shed as monads (permanent tetrads in two species), medium-sized, prolate-spheroidal to subprolate and tricolporate. A substantial amount of variation is found in pollen size, equatorial outline (lobate, subtriangular, circular and hexagonal) and sexine ornamentation type ((micro)rugulate, striate, granulate and gemmate). Moreover, orbicules were present on the inner locule wall in all specimens examined. Their abundance, degree of fusion with tapetal membrane and aggregation vary considerably. We can conclude that Ebenaceae pollen is more heterogeneous than previously assumed. We traced palynological synapomorphies for groups at different taxonomic levels: subfamily level (pollen size, pollen wall stratification and aperture morphology), generic level (size, equatorial outline and sexine ornamentation types) and subgeneric clades (size, ectocolpus morphology, equatorial outline and sexine ornamentation subtypes) respectively. The granular infratectum and the unique sculpturing pattern on the orbicule walls are the most discriminating pollen features for subfamily Ebenoideae. (c) 2008 Elsevier B.V. All rights reserved. ispartof: Review of palaeobotany and palynology vol:153 issue:3 pages:336-353 status: published

Modern pollen precipitation studies were carried out on a regional scale in the territory of the classical city of Sagalassos (Southwest Turkey). 57 moss cushions and 7 soil samples from different vegetation types were analysed palynologically. The resulting pollen spectra were grouped into 14 vegetation groups, which were examined using discriminant analysis and principal components analysis. These numerical procedures are applied to display the structure in the data set in a comprehensive way. Some of the modern spectra groups seem to be well-defined, whereas others are difficult to distinguish from each other. After the relationships between the modern pollen spectra had been analysed, the fossil data from a core from the marsh of Gravgaz were added to the data set so that any similarities between fossil and modern spectra could be seen. A joint principal components analysis of the modern and fossil pollen spectra revealed that the pollen spectra from the earliest (ca. 2600-2500 BP; Cal. 830-590 BC till 790-520 BC) and the latest (starting at ca. 1300 BP; Cal. 660-780 AD) pollen assemblage zones have modern counterparts. On the other hand, the pollen spectra from the pollen assemblage zone dominated by Artemisia (ca. 2500-2300 BP; Cal. 790-520 BC till 410-210 BC) and from the pollen assemblage zone that indicated the practice of arboriculture (ca. 2300-1300 BP; Cal. 410-210 BC till 660-780 AD) have no close modern analogues, although individual tabulated pollen percentages revealed some similarities with some modern spectra groups.

Pyrene and pollen morphology of several neo- and paleotropical Geophila species is documented and discussed. Pyrenes show distinct morphological variation. They have one central or several adaxial ribs and are straight or twisted. Neotropical species only have twisted pyrenes, whereas Madagascan species have straight ones. Both pyrene types occur on the tropical African mainland and in tropical Asia. The genus is eurypalynous, including inaperturate, colpate and pantoporate pollen. The paper includes the first record of operculate pollen in the Rubiaceae, viz. in Geophila repens var. repens. Pyrenes as well as pollen morphology indicate that the varieties of the pantropical species G. repens need recognition at the specific level.

Pollen diagrams from mountain lakes and marshes in SW Turkey show evidence of intensive anthro pogenic influence in the landscape between 3500 and 1300 BP. Three cores from within the territory of the classical city Sagalassos (Western Taurus, Pisidia) were palynologically analysed to make a reconstruction of the past vegetation in the territory of Sagalassos and to estimate the impact of its inhabitants on the landscape in Pisidia. Two cores originate from an intramontane marsh (Gravgaz; elevation 1215 m) and one from a seasonal intramontane lake (ÇanaklK; elevation 1030 m). Human acitivity is apparent from c. 2530 BP in the pollen diagrams. A deforestation phase/‘disturbance’ phase (from c. 2530 BP/c. 2480 BP till c. 2280 BP/c. 2270 BP), anthropogenically or climatologically driven, precedes a cultivation period (arboricultural phase) (from c. 2280 BP/2270 BP till c. 1480 BP/c. 1270 BP). The results of the pollen analyses of the three cores are compared and show many similarities. There are also similarities with other cores from SW Turkey, although the arboricultural phase (mainly olive cultivation) occurs later in the cores from the Sagalassos territory than in other cores from SW Turkey.

The pollen morphology and distribution of orbicules were investigated in ten species of the genus Coptosapelta (Rubiaceae) using light, scanning electron and transmission electron microscopy. In general, Coptosapelta pollen is three- to five-pororate and suboblate to oblate-spheroidal. The sexine ornamentation varies from psilate to reticulate, and the pollen-wall stratification lacks columellae. 'Droplets' are observed on the inner nexine surface. Distinct orbicules are found in five species. Orbicules are often lobed and appear to be aggregated and embedded in the tapetal remnants of the locule wall. Ultrastructurally, a single, flattened core is frequently observed. Coptosapelta has a unique pollen type within Rubiaceae and does not resemble possibly related genera. Pollen characteristics provide additional evidence supporting earlier findings that Coptosapelta represents an isolated lineage in Rubiaceae.

Two travertine sections in the valley of Baskoy, near the archaeological site of Sagalassos have been palynologically investigated. The base of one of these sections has been dated to 9000±600 yr B.P. by the U/Th dating technique. The pollen diagrams of both sections reveal the importance of deciduous Quercus and Betula woodlands during deposition of the travertine. The development of woodlands in the early Holocene implies an increase in humidity after the Late Pleistocene. An annual precipitation of at least 500 mm/yr is suggested. A study of the δ18O values of the travertines in the sections indicates a change to higher precipitation temperatures of the travertines and hence a climatic change to higher air temperatures around 9000±600 yr B.P. This increase in temperature is not documented in the pollen diagrams. The evaluation of the local pollen curves provides additional information on the depositional environment. The facies and pollen analyses indicate that the travertines were deposited in a fluvial–barrage system. High abundances of Cyperaceae pollen suggest a marshy environment and fluctuating water levels of this early Holocene fluvial-barrage system. High percentages of Poaceae and/or Aster and Mentha–Thymus pollen types point to drier local conditions at the beginning and the end of the travertine accumulation of both sections.