Development of inflorescences and flowers in Fabaceae subfamily Dialioideae: an evolutionary overview and complete ontogenetic series for Apuleia and Martiodendron

The goal of this study was to better understand the origin and development of flowers and inflorescences in the newly established subfamily Dialioideae, an unusual and morphologically variable clade of Fabaceae due to its varied levels of floral reduction. We present here the complete ontogenetic series for two species characterizing different levels of floral reduction: Apuleia leiocarpa, an andromonoecious species with trimerous flowers; and Martiodendron fluminense, a species lacking the inner whorl of stamens. We also performed a literature review and herbarium specimen survey of the inflorescence and floral morphology of the other 15 genera in Dialioideae. Among the exclusive traits of Apuleia found here are the absence of two sepals and petals from initiation, the simultaneous initiation of the sepals (never before documented for Dialioideae), the absence of carpel initiation in staminate flowers and the formation of the carpel in the staminal whorl of monoclinous flowers, with the presence of a nectariferous hypanthium in both flower types. In Martiodendron the two exclusive traits are the heteromorphic development of stamens of the outer whorl, with the abaxial one being the last to elongate, and the possible initiation of an inner staminal whorl, which stops developing immediately thereafter and is no longer visible at anthesis. Among the potential synapomorphies for the subfamily are the absence of bracteoles and a pair of bracts subtending a triad of flowers or inflorescence axes, the distichous anthotaxy of the thyrsoid inflorescences, the bidirectional initiation of the sepals and the simultaneous initiation of the stamens.

Can the anatomy of abnormal flowers elucidate relationships of the androecial members in the ginger (Zingiberaceae)?

Background Interpretation of the floral structure of Zingiberaceae has long concentrated on the relationships of the androecial members. It has been suggested that the labellum is composed of two structures rather than three or five, and the glands are not only the epidermis of the ovary but are similar to nectaries. Results Serial sections were used to observe the vasculature of normal and two-staminate flowers in Alpinia intermedia ‘shengzhen’. Floral diagrams were drawn to interpret the morphological category of the floral organs and the relationships of the androecial members. Androecial vascular bundles were associated with carpellary dorsal bundles (CDBs) and parietal bundles (PBs) in a Zingiberales phylogeny setting using ancestral state reconstruction. Anatomical observations demonstrate that the fertile stamen(s) incorporate parietal strands both in normal and two-staminate flowers. The three appendages represent the three members of the outer whorl of the androecium while the labellum represents the inner whorl of the androecium in the two-staminate flower. Reconstruction of the origin of the vascular system in the androecium suggests that the outer whorl of androecium receives its vascular supply from the CDBs and the inner whorl of androecium receives from the PBs in both the basal banana group and the more derived ginger clade. Conclusions The present study adds to a growing body of literature suggesting that anatomy of abnormal flowers may not provide enough evidence for elucidating the relationships of the androecial members. Abnormal flowers are diverse in the Zingiberaceae and may derive from different types of mutations.

Recognition of Truncorotalia Crassaformis As a Modern Planktonic Foraminiferal Morphospecies in the Caribbean and Equatorial Atlantic Ocean and Proposal of a Neotype

To clarify patterns of within-population variation in Truncorotalia crassaformis and their bearing on selection of a neotype, the shape of shells from two Caribbean sediment traps was analyzed statistically. These data were compared with those from a Holocene equatorial Atlantic core, from topotypes of Globigerina crassaformis Galloway and Wissler (Lomita Quarry, California), and from type specimens of Globorotalia oceanica. This approach was used because the holotype (now destroyed) was the only designated specimen. Morphometric analyses of shells in axial and spiral orientations use data from equally-spaced coordinates around their outlines recorded from SEM imagery. Special attention is given to the profile of the last-formed chamber and to development of a keel at its periphery. Comparison of data from 150 m and 700 m traps shows that the former population includes only small, possibly pre-adult specimens that are non-crusted. Shell shape, especially in axial orientation is much less variable than in the 700 m sample which includes many encrusted and kummerform specimens. Variation in the Holocene sample is closely similar to that in the 700 m trap. Between group comparisons show that the holotype and two paratypes of Globorotalia oceanica plot within the morphospaces of the trap and Holocene samples. All are referred to Truncorotalia crassaformis on the basis of their shape, calcification patterns, and notably the absence of a keel or carina on the final chamber. It is likely that its holotype had this attribute. The axial shape of the neotype is similar to the modelled mean shape of specimens from the sediment traps. Topotypes with a keel on all chambers of the outer whorl are identified as Truncorotalia aff. crassacarina.

Floral development and vascularization help to explain merism evolution inPaepalanthus(Eriocaulaceae, Poales)

BackgroundFlowers in Eriocaulaceae, a monocot family that is highly diversified in Brazil, are generally trimerous, but dimerous flowers occur inPaepalanthusand a few other genera. The floral merism in an evolutionary context, however, is unclear.Paepalanthusencompasses significant morphological variation leading to a still unresolved infrageneric classification. Ontogenetic comparative studies of infrageneric groups inPaepalanthusand in Eriocaulaceae are lacking, albeit necessary to establish evolution of characters such as floral merism and their role as putative synapomorphies.MethodsWe studied the floral development and vascularization of eight species ofPaepalanthusthat belong to distinct clades in which dimery occurs, using light and scanning electron microscopies.ResultsFloral ontogeny in dimerousPaepalanthusshows lateral sepals emerging simultaneously and late-developing petals. The outer whorl of stamens is absent in all flowers examined here. The inner whorl of stamens becomes functional in staminate flowers and is reduced to staminodes in the pistillate ones. In pistillate flowers, vascular bundles reach the staminodes. Ovary vascularization shows ventral bundles in a commissural position reaching the synascidiate portion of the carpels. Three gynoecial patterns are described for the studied species: (1) gynoecium with a short style, two nectariferous branches and two long stigmatic branches, in most species; (2) gynoecium with a long style, two nectariferous branches and two short stigmatic branches, inP. echinoides; and (3) gynoecium with long style, absent nectariferous branches and two short stigmatic branches, inP. scleranthus.DiscussionFloral development of the studied species corroborates the hypothesis that the sepals of dimerous flowers ofPaepalanthuscorrespond to the lateral sepals of trimerous flowers. The position and vascularization of floral parts also show that, during dimery evolution inPaepalanthus, a flower sector comprising the adaxial median sepal, a lateral petal, a lateral stamen and the adaxial median carpel was lost. In the staminate flower, the outer whorl of staminodes, previously reported by different authors, is correctly described as the apical portion of the petals and the pistillodes are reinterpreted as carpellodes. The occurrence of fused stigmatic branches and protected nectariferous carpellodes substantiates a close relationship betweenP.sect.ConodiscusandP.subg.Thelxinoë. Free stigmatic branches and exposed carpellodes substantiate a close relationship betweenP. sect.Diphyomene,P. sect.EriocaulopsisandP. ser.Dimeri. Furthermore, the loss of nectariferous branches may have occurred later than the fusion of stigmatic branches in the clade that groupsP. subg.ThelxinoëandP. sect.Conodiscus.

The Genus Dasymaschalon (Annonaceae) in Thailand

A comprehensive taxonomic revision of the genus Dasymaschalon (Annonaceae) in Thailand is presented. Twelve species are recognized, including five that are newly described and one new nomenclatural combination, viz. D. acuminatum sp. nov., D. angustifolium sp. nov., D. dasymaschalum, D. echinatum sp. nov., D. filipes, D. glaucum, D. grandiflorum sp. nov., D. lomentaceum, D. macrocalyx, D. obtusipetalum sp. nov., D. sootepense, and D. wallichii comb. nov. Previous taxonomic confusion regarding the relationship between Dasymaschalon and Desmos is discussed. The most significant diagnostic difference between the two genera is the number and arrangement of petals: Dasymaschalon species have only three petals (homologous with the outer whorl of other Annonaceae) that are apically connivent to form an enclosed pollination chamber, whereas Desmos species have two whorls of three petals which are basally constricted and apically free.

Flowers of Bienertia cycloptera and Suaeda aralocaspica (Chenopodiaceae) complete the life cycle performing single-cell C4 photosynthesis

Leaves and cotyledons of the terrestrial C4 plants, Bienertia cycloptera Bunge ex Boiss. and Suaeda aralocaspica (Bunge) Freitag & Schütze (Chenopodiaceae), accomplish C4 photosynthesis within individual chlorenchyma cells: each species having a unique means of intracellular spatial partitioning of biochemistry and organelles. In this study the chlorenchyma tissue in flowers and stems of these species was investigated. Flowers have an outer whorl of green tepals with a layer of chlorenchyma cells, which are located on the abaxial side, exposed to the atmosphere. Anatomical, immunocytochemical, western blots and starch analyses show that the chlorenchyma cells in tepals are specialised for performance of single-cell C4 photosynthesis like that in leaves. In the tepals of B. cycloptera, chlorenchyma cells have a distinctive central cytoplasmic compartment, with chloroplasts which contain Rubisco, separated by cytoplasmic channels from a peripheral chloroplast-containing compartment, with phosphoenolpyruvate carboxylase (PEPC) distributed throughout the cytoplasm. In the tepals of S. aralocaspica, chlorenchyma cells have chloroplasts polarised towards opposite ends of the cells. Rubisco is found in chloroplasts towards the proximal end of the cell and PEPC is found throughout the cytoplasm. Also, green stems of B. cycloptera have a single layer of the specialised C4 type chlorenchyma cells beneath the epidermis, and in stems of S. aralocaspica, chlorenchyma cells are scattered throughout the cortical tissue with chloroplasts around their periphery, typical of C3 type chlorenchyma. During reproductive development, green flowers become very conspicuous, and their photosynthesis is suggested to be important in completion of the life cycle of these single-cell C4 functioning species.

(9) Compositional Characterization of a Garlic Germplasm Collection

A USDA germplasm collection of garlic (Alliumsativum) and related species (A. ophioscorodon, A. longicuspis) has been evaluated for horticultural characteristics and composition under California production conditions for several years. In 2004, 198 of the 217 accessions in the collection were evaluated. Bulbs were manually harvested late June to early July, cured about 3 weeks shaded at ambient temperatures, and the outer whorl of cloves manually peeled. Bulb and clove weights and percentage of dry matter were determined. Freeze-dried garlic powder was analyzed for alliin (precursor of flavor and health compounds) concentrations by HPLC. Thiosulfinates (mostly allicin, responsible for flavor and pungency) were determined by a spectrophotometric assay. Among the accessions evaluated in 2004, the percentage of dry matter ranged from 32.8% to 44.9%. Alliin content varied from 8.9 to 29.7 mg·g-1, and thiosulfinate concentrations ranged from 32.7 to 114.0 μmol·g-1. For comparison, the widely grown varieties California Early and California Late averaged 39.5% and 40.8% dry matter, 18.6 and 20.6 mg·g-1 alliin, and 68.1 and 78.8 μm·g-1 thiosulfinates.

Maclurina manitobensis(Whiteaves) (Ordovician Gastropoda): the largest known Paleozoic gastropod

The concept of the Ordovician gastropod genusMacluritesLe Sueur, 1818, at present includes much variation.MaclurinaUlrichinUlrich and Scofield, 1897, is removed as a subjective synonym ofMacluritesand reestablished as a separate genus. Species ofMacluriteswith spiral grooves on the outer whorl surface and a relatively small umbilicus are transferred toMaclurina. Maclurina manitobensis(Whiteaves, 1890) forms a distinctive part of the Late Ordovician-age “Arctic Ordovician fauna.” An unusually large specimen (25 cm in diameter) from the Bighorn Dolomite (Upper Ordovician), Wyoming, is illustrated; this Wyoming specimen is the volumetrically largest Paleozoic gastropod ever reported.

An updated interpretation of the androecium of the Fumariaceae

A study of the floral development of Dicentra formosa, Corydalis lutea, and Hypecoum procumbens was carried out to better understand the nature of the androecium in Fumariaceae. Sepals emerge successively in a median position and are followed by two alternating pairs of petals. Four stamen primordia are formed in a diagonal position. They are promptly followed by two lateral, slightly externally inserted primordia. In Dicentra and Corydalis the stamens arise on two crescent-shaped protuberances. In Hypecoum, four diagonal androecial primordia fuse into two median staminal complexes. The gynoecium emerges as a girdling primordium with four growth centers. Different interpretations of the androecium are discussed. It is demonstrated that the androecium in the Fumariaceae consists basically of two whorls: an outer whorl of four alternipetalous stamens and an inner whorl of two lateral stamens superposed to the outer petals. The monothecal nature of the alternipetalous stamens and the fusion of the stamens in two triplets is probably caused by a spatial median compression of the flower bud. The androecium of Hypecoum is the result of interprimordial growth between the pairs of monothecal stamens, and the androecium of Pteridophyllum arises through the loss of the two lateral stamens superposed to the outer petals. Key words: Fumariaceae, floral development, androecium, stamen whorls.

Floral Morphology of Eucalyptus melliodora A. Cunn. ex Schau. And Comparisons With Other Eucalypt Species

The important phases of floral development in E. melliodora from bud initiation to anthesis and style abscission are documented by means of scanning electron micrographs. Thirteen phases of bud development from first indication of operculum abscission to style abscission are presented, as well as the timing and duration of each phase. Anther dehiscence commences prior to flower opening and no pollen grains were observed on flowers 2 days after opening. Secondary transportation of pollen after deposition is possible. Nectar secretion did not commence until after pollen was shed and the stigma became receptive. Although individual flowers were protandrous, there was some overlap within a single inflorescence between pollen shed and the 'wet stigma' phase, suggesting that geitonogamy was possible. The style did not increase in length following anthesis, a common feature in Eucalyptus, leaving the stigma in close proximity with the anthers. There was a graduation in filament length from the outer to inner whorls. The innermost anthers produced the most pollen grains while the outermost were staminodal. There was considerable difference between the number of stamens (71-312), staminodes (0-83) and pollen grains per anther (643-1790) found in the six species examined. Stamen length in all species increased across the staminophore from 1.82-6.99 mm in the inner whorl to 4.84-12.61 mm in the outer whorl.