Floral anatomy of the Milla complex genera (Themidaceae)

2010 ◽  
Vol 87 ◽  
pp. 1
Author(s):  
Sofía Loza-Cornejo ◽  
Fernando Chiang Cabrera ◽  
Eduardo Ruiz-Sanchez ◽  
José Luis Villaseñor ◽  
Mario Ernesto Suárez-Mota ◽  
...  

Floral morpho-anatomy of the Milla complex genera (Themidaceae) was studied with the aim to confirm the occurrence of a gynophore in Dandya, to determine if there are anatomical characters that allow to distinguish Dandya from the rest of genera of the complex (Behria, Bessera, Jaimehintonia, Milla, and Petronymphe), and to understand their evolution. Floral buds of ten species of the Milla complex were studied through the standard paraffin microtechnique. The results demonstrated the presence of a gynophore without pith in Dandya, while the other genera have a gynophore with pith. In addition, Dandya differs from the other genera of the complex by a closed-stigma with external papillae, nectary cavities of horned-shape with tabular epidermal cells, and filaments with 4-strata of parenchyma cells. Behria and Bessera share characters such as connated stamens and an ovary with the external epidermis papillose. Attributes like gynophore with pith, percentage of adnnation between ovary and floral tube of 20-30%, stigma with an open ending, and nectary cavities with discoidal shape are probably ancestral conditions in the Milla complex, from which transformation of character states occurred mostly in Dandya.

1933 ◽  
Vol 9 (5) ◽  
pp. 458-485 ◽  
Author(s):  
S. M. Pady

The genera that constitute the Pucciniastreae display a wide variation in the type of teliospore produced, as well as in the time and place of production. From the standpoint of development, however, there is a general situation that is common. In all genera primordial cells are formed from enlarged hyphal cells of the mycelium. These give rise to teliospore initials which are in the epidermal cells in Calyptospora, Milesia, Hyalopsora and Thecopsora, and are subepidermal in the other genera. These initials divide to form the mature teliospores, which are thick or thin walled, and few to many-celled. In all cases the teliospore is the product of a single primordial cell.The teliospores of Calyptospora goeppertiana are formed from a perennial mycelium, which causes a witches' broom and hypertrophied stems on species of Vaccinium. The mycelium gives rise to primordial cells in the cortex just below the epidermis. Each primordial cell pierces the host wall above and the contents pass in to form the initial, which by growth and division becomes the teliospore. The mature teliospores are one- to four-celled, with a thickened, dark brown wall. Development is not simultaneous, but progressive, and the teliospores are first formed in the basal parts, moving slowly upward until every cell of the hypertrophied portion of the stem is completely filled. In four species of Milesia the method of development is similar. The spores, however, are thin walled, and are formed in the epidermal cells of the overwintered fronds of their fern hosts. Thecopsora vacciniorum is similar to Milesia in many respects. The teliospores are intra-epidermal, thin walled and multicellular. In Pucciniastrum the teliospores are subepidermal, and arise from primordial cells, as in Calyptospora, Milesia and Thecopsora. The teliospore initials are closely packed, and the mature spores may form extended crusts. The simplest type of development is found in Uredinopsis, which is generally considered to be the most primitive of the fern rusts. Primordial cells are formed in the same way as in the other genera. These round up to form the initials, and cross walls are laid down to give the mature spores.From these studies two possible lines of development are suggested, both beginning with Uredinopsis. One line would lead through the intra-epidermal forms, as Milesia, Calyptospora, etc., and the other through the subepidermal genera, as Pucciniastrum and Melampsoridium.


Botany ◽  
2013 ◽  
Vol 91 (7) ◽  
pp. 421-430 ◽  
Author(s):  
M.D. Shafiullah ◽  
Christian R. Lacroix

Myriophyllum aquaticum (Vell.) Verdc. produces two morphologically different forms of leaves based on whether they are aerial or aquatic. The objective of this study was to determine whether there are any similarities or differences between these two growth forms during their early stages of development. A comparative developmental study of aerial and aquatic growth forms of M. aquaticum was conducted from a qualitative and quantitative perspective using a scanning electron microscope. The pattern of leaf and lobe initiation such as their origin and shape were similar in both growth forms until the fourth plastochron (stage P4). Differences between the two growth forms became evident from stage P5 onward, where a larger shoot apical meristem (SAM), elongated epidermal cells, shorter and slightly more numerous lobes, as well as the presence of appendage-like structures characterized aquatic growth forms. On the other hand, aerial growth forms had smaller SAM, bulb-like epidermal cells, and longer and slightly less numerous leaf lobes. Significant differences between growth forms were noted for parameters such as volume of SAM, length of terminal, first, and middle lobes, as well as the length from first to last lobes. The volume of the SAM of aquatic shoot tips was always greater than aerial forms. On the other hand, lobes of aerial forms were always longer than the aquatic counterpart during early stages of development. This study on the development of M. aquaticum shows that the aerial and aquatic growth forms diverge from their early stages of development.


2002 ◽  
Vol 62 (2) ◽  
pp. 333-338 ◽  
Author(s):  
W. L. PARAENSE

A redescription of conchological and anatomical characters of the planorbid mollusc Plesiophysa ornata (Haas, 1938) is presented, based on topotypic material and specimens from 14 additional localities in the Brazilian states of Rio Grande do Norte, Paraíba, Sergipe, Bahia, Espírito Santo and Minas Gerais. Due to the close similarity of their shells, a sure discrimination of the five species of Plesiophysa described so far (P. pilsbryi, P. granulata, P. guadeloupensis, P. ornata and P. hubendicki) is only possible through their anatomical features. The present study points to the high probability of synonymy of P. hubendicki with P. ornata. Investigations on the anatomy of P. pilsbryi and P. guadeloupensis are needed to define their taxonomic relation with the other nominal species.


2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Wade B. Worthen ◽  
Parker H. Morrow

In many communities of perching dragonflies (Odonata: Libellulidae), a size-dependent competitive hierarchy creates a positive relationship between male body size and perch height. We tested for this pattern among three similar-sized species:Celithemis elisa,C. fasciata, andC. ornata.Males were caught and photographed from May to July 2015 at Ashmore Heritage Preserve, Greenville County, SC, USA, and perch heights and perch distance to open water were measured. Five indices of body size were measured with ImageJ software: abdomen length, forewing length, hindwing length, area of forewing, and area of hindwing.Celithemis fasciatawas significantly larger than the other two species for all five anatomical characters and used perches that were significantly taller and closer to open water than the other species, though these differences changed over the summer. Aggressive interactions between and within species were tallied and compared to expected distributions based on mean relative abundances derived from hourly abundance counts. Patterns of interspecific aggression were also consistent with a size-dependent hierarchy: the largeC. fasciatawas attacked less frequently, and the smallC. ornatamore frequently, than predicted by their relative abundances. We conclude that even small differences in body size may contribute to niche partitioning in perch selection.


2001 ◽  
Vol 14 (2) ◽  
pp. 175 ◽  
Author(s):  
Andrew C. Rozefelds ◽  
Richard W. Barnes ◽  
Belinda Pellow

The vegetative and reproductive morphology of Vesselowskya Pampanini, southern marara, is described and illustrated in detail. The variation within V. rubifolia (F.Muell.) Pampanini sens. lat. is shown to be greater than has previously been recognised, with the differences identified supporting the recognition of a new segregate species, V. venusta Rozefelds, R.W.Barnes and Pellow sp. nov. Vesselowskya venusta occurs in the Barrington Tops Plateau of New South Wales and differs from V. rubifolia in possessing hairs on the abaxial surface of the sepals and lacking both a prominent distal connective protrusion on the anthers and colleters at the base of the stipules. The two Vesselowskya species are dioecious with a vestigial ovary in staminate flowers and reduced stamens in pistillate flowers. Dioecy is more pronounced in Vesselowskya, than in some Weinmannia species, and in both genera is expressed through reduction in the size of the ovaries in staminate flowers, and stamens in pistillate flowers. Vesselowskya shares with the other genera in the tribe Cunonieae (Pancheria, Weinmannia and Cunonia), a central column in the fruits, and Cunonia-type stipules, but differs from these genera in having valvate aestivation, digitate leaves, craspedodromous secondary venation with secondary veins terminating at a tooth, tuft domatia along the midrib, adaxial epidermal cells with strongly sinuous cell walls and the absence of hydathodes.


Phytotaxa ◽  
2014 ◽  
Vol 172 (1) ◽  
pp. 13 ◽  
Author(s):  
Ruy José Válka Alves ◽  
Alessandra Ribeiro Guimarães ◽  
Claudia De Moraes Rezende ◽  
Laura Di Spirito Braga ◽  
Nílber Gonçalves da Silva

A new giant Vellozia species from the Ouro Branco range, Minas Gerais, is described and compared morphologically to the other dracenoid species. Leaf-anatomical characters and a unique suite of chemical constituents which help to separate the new species from V. compacta, sympatric in the range, are provided. Furthermore we discuss the circumscription of V. compacta and argue that this binomial is applied to a species complex in need of further taxonomic study.


1968 ◽  
Vol 16 (3) ◽  
pp. 451 ◽  
Author(s):  
BR Jackes

The organography and vascular anatomy of the flower of Oligarrhena micrantha R. Br, has been examined in detail. Whilst in general agreement with the other members of the tribe Styphelieae, it does exhibit a greater degree of carpel sterilization, and supports the suggestion that progressive sterilization has been occurring within this tribe.


1974 ◽  
Vol 22 (2) ◽  
pp. 211 ◽  
Author(s):  
G Scurfield ◽  
CA Anderson ◽  
ER Segnit

Scanning electron microscopy has been used to examine silica isolated by chemical means from the wood of 32 species of woody perennial. The silica consists of aggregate grains lying free in the lumina or in ray and xylem parenchyma cells in 24 of the species. It occurs as dense silica in the other species, filling the lumina or lining the internal surfaces of vessels (and fibres) in all cases except Gynotroches axillaris where it is deposited in ray parenchyma cells. Infrared spectra and X-ray diffraction diagrams, obtained for specimens of both sorts of silica, are indistinguishable from those for amorphous silica. Aggregate grain and dense silicas are also alike in that their differential thermal analysis curves show a rather broad endothermic peak between 175° and 205°C. The results are discussed in relation to possible modes of deposition of the two sorts of silica and the tendency for silica in ray parenchyma cells to be associated with polyphenols.


Phytotaxa ◽  
2019 ◽  
Vol 402 (2) ◽  
pp. 126
Author(s):  
TOSHIHIRO YAMADA ◽  
TAKAE F. YAMADA ◽  
KAZUO TERADA ◽  
TAKESHI A. OHSAWA ◽  
ATSUSHI YABE ◽  
...  

A new fossil cycad species, Sueria laxinervis, is described from the Upper Cretaceous (Maastrichtian) Quiriquina Formation in Cocholgüe, Bíobío Region, Chile. The generic assignment is supported by the taeniopterid-type leaf with haplocheilic stomata and sinuate anticlinal walls of leaf epidermal cells, while S. laxinervis clearly differs from the other two described Sueria species in its sparse veins and large epidermal cells. The vascular bundles of the midrib are arranged in an inverted-omega shape, supporting the placement of Sueria in Cycadales.


Phytotaxa ◽  
2013 ◽  
Vol 144 (2) ◽  
pp. 45 ◽  
Author(s):  
WILLIAM CETZAL-IX ◽  
GERMAN CARNEVALI ◽  
ELIANA NOGUERA-SAVELLI ◽  
DAMELIS JAUREGUI

A putative natural hybrid between Cohniella ascendens and C. brachyphylla (Orchidaceae, Oncidiinae) from western Costa Rica, C. ×francoi, is herein newly described, illustrated and characterized based upon both morphological and anatomical characters. This taxon hybrid is most similar to C. ascendens but the flowers show intermediate characters between the putative parents. Cohniella ×francoi is similar to C. ascendens in its semipendulous inflorescences, callus shape, cylindrical column base with linear oblong wings, and obovate stigmatic cavity plus several anatomical characters. On the other hand, it is similar to C. brachyphylla in the oblong to subquadrate lateral lobes of the labellum that are in the same plane as the central lobe, and the rectangular disc of the labellum with a lateral extension of the callus in the margins. A table of diagnostic characters for the new hybrid and its putative parents, a comparative figure, and a map showing their geographical distributions are also provided.  Cohniella ×francoi, un híbrido natural entre Cohniella ascendens y C. brachyphylla (Orchidaceae, Oncidiinae) del oeste de Costa Rica es aquí descrito, ilustrado y caracterizado por caracteres morfológicos y anatómicos. El nuevo híbrido es más similar a C. ascendens pero las flores presentan caracteres intermedios entre sus padres putativos. Cohniella ×francoi se parece a C. ascendens en la inflorescencia semipéndula, la forma del callo, la columna cilíndrica con las alas linear oblongas y la cavidad estigmática obovada, además de varios caracteres anatómicos. Por otro lado, es similar a C. brachyphylla por los lóbulos laterales del labelo oblongos a subcuadrados y extendidos en el mismo plano que el lóbulo central y el disco rectangular con extensiones laterales del callo en los márgenes. Adicionalmente, proporcionamos una tabla de caracteres diagnósticos para el nuevo híbrido y sus padres putativos, una figura comparativa y un mapa detallando las distribuciones geográficas de los tres taxones.


Sign in / Sign up

Export Citation Format

Share Document