Leaf Axil Anatomy of the Araucariaceae

1987 ◽  
Vol 35 (6) ◽  
pp. 631 ◽  
Author(s):  
GE Burrows
Keyword(s):  
Leaf Axil ◽  
Vascular Cylinder ◽  
Axillary Meristem ◽  
External Appearance ◽  
The Family ◽  
Vascular Connections

Well defined, persistent meristems, which possess neither a bud-like organisation nor vascular connections with the central vascular cylinder, were found in the apparently blank leaf axils of six species of Agathis and 13 species of Araucaria. In other conifers, leaf axils of similar external appearance are usually reported to lack, or gradually lose, any specialised bud-forming tissues. Meristems were found in all axils investigated and in this respect the Araucariaceae approach the typical angiospermous condition of a bud in each leaf axil. Evidence is presented that the type of axillary meristem ontogeny previously described for A. cunninghamii may be widespread in the family.

Axillary Meristem Ontogeny in Araucaria cunninghamii Aiton ex D Don

1986 ◽  
Vol 34 (4) ◽  
pp. 357 ◽  
Author(s):  
GE Burrows
Keyword(s):  
Vascular Cylinder ◽  
Axillary Meristem ◽  
Bud Formation ◽  
Undifferentiated State ◽  
Axillary Meristems ◽  
Typical Condition ◽  
Terminal Shoot ◽  
Araucaria Cunninghamii ◽  
Vascular Connections ◽  
Periderm Formation

The presence of axillary meristems in apparently blank leaf axils from the main stem of 2-year-old Araucaria cunninghamii is demonstrated. These meristems are groups of cells of meristematic appearance, which possess neither a bud-like organisation nor vascular or pro-vascular connections with the central vascular cylinder. They are first discernible in the axils of the recently initiated leaves, where each meristem is delimited from the vacuolating cortex by a shell zone. The axillary meristems then persist indefinitely in an inhibited, undifferentiated state, unless stimulated to bud formation by decapitation of the terminal shoot apex. They are exogenous in origin but are subsequently buried beneath the stem surface by the formation of localised periderms, the bark patches, and are not abscissed when extensive periderm formation begins. A. cunninghamii is apparently unique amongst conifers in possessing distinct, long-lived, exogenously initiated meristems or bud primordia in macroscopically blank leaf axils. The meristems are found in most leaf axils not occupied by branch buds. In this respect A. cunninghamii differs from most conifers and approaches the typical condition of angiosperms. The axillary meristems are inter- mediate in form between previously described vegetative axillary structures in gymnosperms and angiosperms.

scholarly journals Rhizome and root anatomy of 14 species of Bromeliaceae

Rodriguésia ◽  
2008 ◽  
Vol 59 (1) ◽  
pp. 113-128 ◽  
Author(s):  
Suzana Lúcia Proença ◽  
Maria das Graças Sajo
Keyword(s):  
Water Absorption ◽  
Root Anatomy ◽  
Vascular Cylinder ◽  
Anatomical Features ◽  
Cerrado Biome ◽  
The Family ◽  
And Storage

ABSTRACT The anatomy of rhizomes and roots of 14 species of Bromeliaceae that occur in the cerrado biome were studied with the aim of pointing out particular anatomical features of the family and possible adaptations related to the environment. All the rhizomes are similar although some have root regions growing inside the cortex. In some species the vascular cylinder of the rhizome is clearly limited from the cortex. The roots are also very similar, although the coating tissue differs in roots growing inside the rhizome or externally to it and the cortex has a variable organization according to the region. The studied species present anatomical features that are associated to water absorption and storage, showing that they are adapted to the cerrado environment.

scholarly journals Vestidos y adornos: la crítica a las apariencias exernas a través de la prensa española (finales del siglo XVIII- siglo XIX) = Dresses and ornaments: criticism of outward appearances through the Spanish press (late eighteenth century-nineteenth century)

2017 ◽  
pp. 137
Author(s):  
Francisco Javier Crespo Sánchez
Keyword(s):  
Nineteenth Century ◽  
Eighteenth Century ◽  
External Appearance ◽  
Negative Results ◽  
Late Eighteenth Century ◽  
The Family ◽  
Late Eighteenth ◽  
Siglo Xix ◽  
Spanish Press ◽  
Newspaper Articles

<p>Este trabajo estudia los discursos que sobre la moda y el lujo recogió la prensa española (especialmente la cercana al pensamiento religioso) entre finales del siglo XVIII y el siglo XIX con el objetivo de entender qué motivos se indicaban para querer controlar la apariencia externa. Así, elementos como la moralidad, la economía o los resultados negativos que provocaba en la mujer y en la familia, han sido los principales temas analizados a través de los artículos periodísticos.</p><p><strong>Abstract</strong></p><p>This paper studies the discourses about fashion and luxury appeared in the Spanish press (especially in the religious press) between the late eighteenth century and the nineteenth century in order to understand what reasons were indicated to control the external appearance. Thus, elements such as morality, economy or the negative results caused in women and the family, have been the main topics discussed through newspaper articles.</p>

Syncarpia and Tristaniopsis (Myrtaceae) possess specialised fire-resistant epicormic structures

2008 ◽  
Vol 56 (3) ◽  
pp. 254 ◽  
Author(s):  
Geoffrey E. Burrows
Keyword(s):  
Common Ancestor ◽  
Secondary Xylem ◽  
Outer Region ◽  
Leaf Axil ◽  
Crown Fire ◽  
Structural Adaptation ◽  
The Family

On a worldwide basis epicormic resprouting after intense or crown fire is extremely rare, but is quite common in the eucalypts. Recent research has shown that the eucalypts have a highly modified epicormic structure that provides the bud-forming tissues with excellent protection from heat. A small number of non-eucalypts from the Myrtaceae have also been recorded as post-fire epicormic resprouters and it was considered of interest to determine whether this response was achieved through a similar or different structural adaptation. Leaf axils and epicormic structures of two species of Syncarpia and three species of Tristaniopsis were examined anatomically. Although the leaf axil anatomy of Syncarpia and Tristaniopsis was quite different (and different from that of the eucalypts), the epicormic structure was similar to that of the eucalypts, as the outer region of each epicormic strand possessed several strips of cells of meristematic appearance that were best developed in the innermost bark or even the outermost secondary xylem. As Syncarpia, Tristaniopsis and the eucalypts are only distantly related to each other within the Myrtaceae, it appears that this specialised fire-adapted epicormic structure may have developed multiple times within the family or originated from a common ancestor of the family.

Initiation and structure of the secondary vascular system in Phytolacca dioica (Phytolaccaceae)

1984 ◽  
Vol 62 (12) ◽  
pp. 2580-2586 ◽  
Author(s):  
Bruce K. Kirchoff ◽  
Abraham Fahn
Keyword(s):  
Vascular System ◽  
Secondary Growth ◽  
Tissue Response ◽  
Vascular Cambium ◽  
Vascular Cylinder ◽  
Primary Growth ◽  
Secondary Thickening ◽  
Dividing Cells ◽  
Cathodic Side ◽  
Vascular Connections

Phytolacca dioica (L.) is characterized by anomalous secondary thickening by means of supernumerary cambia. After a period of primary growth and the formation of an initial (normal) vascular cambium, supernumerary cambia are initiated outside of the primary vascular cylinder. The initiation of the first supernumerary cambium takes place through approximately the number of nodes equal to the denominator of the phyllotactic fraction characterizing a given axis. At each node a segment of supernumerary cambium is initiated opposite the leaf traces supplying the leaf inserted at that node. The segments of differentiated cambium are preceded by regions of obliquely and anticlinally dividing cells. In the single juvenile axis studied supernumerary cambial segments also appear above the node to the cathodic side of the entering leaf traces, and opposite the medullary bundle immediately anodic to these traces. Vascular connections among the primary and supernumerary vascular cylinders occur between leaf insertions on the same orthostichy. The levels at which these connections occur vary among stems. The switch from ordinary to anomalous secondary growth may be caused by a change in tissue response to stimuli produced by leaves.

Urolabida graziae, new urostylidid species from the Philippines with comments on the current taxonomy and systematics of the family (Hemiptera: Heteroptera: Urostylididae)

Zootaxa ◽  
2021 ◽  
Vol 4958 (1) ◽  
pp. 702-712
Author(s):  
MARCOS ROCA-CUSACHS ◽  
MERCEDES PARIS ◽  
ALMA MOHAGAN ◽  
SUNGHOON JUNG
Keyword(s):  
New Species ◽  
Type Species ◽  
New Genus ◽  
The Philippines ◽  
Type Specimens ◽  
External Appearance ◽  
The Family ◽  
A New Species ◽  
Male Genital

A new species of Urostylididae from the Philippine islands (Mindanao) is herein described. This new species, similar to Urolabida bipunctata Stål, 1871, differs from the latter in the shape of the external male genitalia. Urolabida bipunctata and the new species, Urolabida graziae Roca-Cusachs, sp. nov., are extremely similar in external appearance, and fit into the (incomplete) description of genus Urolabida Westwood, 1837. The examination and comparison with the type specimens of other Urostylididae species, especially the male genital capsule, clearly separates this two species from Urolabida tenera Westwood, 1837, the type species of the genus Urolabida, however the taxonomy of this group is not resolved and needs a deep revision, therefore we refrain from description of a new genus-group taxon here. Additionally, images of the type specimens of Urolabida tenera, Urostylis histrionica Westwood, 1837, and Urostylis punctigera Westwood, 1837, are provided and discussion on the current systematics and classification of the family, and particularly of genus Urolabida are also given. 

A new species and two new records of the ground spider genus Apopyllus (Araneae, Gnaphosidae) from Paraguay

Zootaxa ◽  
2019 ◽  
Vol 4664 (4) ◽  
pp. 594-600
Author(s):  
YOLANDA M. G. PIÑANEZ ESPEJO ◽  
JOHN A. KOCHALKA ◽  
BOLÍVAR R. GARCETE BARRETT
Keyword(s):  
New Species ◽  
South America ◽  
New Records ◽  
Southern Mexico ◽  
External Appearance ◽  
Southern South America ◽  
Distribution Ranges ◽  
The Family ◽  
Small Genus ◽  
A New Species

The family Gnaphosidae consist of 158 genera and 2530 species worldwide. In South America there are 35 genera (World Spider Catalog 2019) considering Apopyllus Platnick & Shadab, 1984, a small genus of ground hunting spiders (Cardoso et al. 2011) that includes ten American species, of which eight have been recorded from southern South America. Their known distribution ranges from southern Mexico through Colombia, Bolivia, Perú, Chile, Brazil and Argentina (World Spider Catalog 2019). In Paraguay, the genus was first mentioned in an invertebrate checklist (see Kochalka et al. 1996). First studies on the genus and its taxonomic placement were made by Platnick & Shadab (1984), and more recently a revision of the genus was undertaken by Azevedo et al. (2016), including four new Brazilian species. Even though the external appearance of Apopyllus is similar to other gnaphosids, specifically taking into consideration the Echemus group, spiders with plain colored abdomens, sometimes presenting chevrons in the opisthosoma, and with developed scutum in males (Murphy 2007), females and males can be differentiated by the more elaborated and intricated genitalia structures (see Azevededo et al. 2016). Apopyllus is most similar to Apodrassodes Vellard, 1924 both having a similar elongate embolus (Fig. 3e) and a membranous tegular extension (Fig. 3d) (Platnick & Shadab 1984), and to the genera Nopyllus Ott, 2014, but differ from the later by the presence of a scutum (Fig. 3a) in males and by the presence of a median apophysis (Fig. 3e) on the bulb (Ott, 2014). 

Wollemi Pine (Wollemia nobilis, Araucariaceae) Possesses the Same Unusual Leaf Axil Anatomy as the other Investigated Members of the Family

1999 ◽  
Vol 47 (1) ◽  
pp. 61 ◽  
Author(s):  
Geoffrey E. Burrows
Keyword(s):  
The Other ◽  
Leaf Axil ◽  
Adult Morphology ◽  
Typical Member ◽  
The Family ◽  
Axillary Meristems

Most leaf axils of most conifers are devoid of any bud-forming potential. Bycontrast, the numerous, apparently blank, leaf axils of the previouslyinvestigated species of the Araucariaceae possess unusual, if not unique,little-differentiated axillary meristems which have neither a bud-likeorganisation nor vascular or provascular connections with the central vascularcylinder. These meristems are exogenous in origin but are buried beneath thestem surface by the formation of localised periderms. Leaf axils fromplagiotropic branch shoots of juvenile and adult morphology and fromorthotropic leaders of adult morphology of the recently described Wollemi pine(Wollemia nobilis W.G.Jones, K.D.Hill & J.M.Allen)have been found to possess a anatomy similar to that previously described forthe Araucariaceae. Thus, W. nobilis is, on the basis ofits leaf axil anatomy, a typical member of the Araucariaceae.

scholarly journals Auxin Depletion from the Leaf Axil Conditions Competence for Axillary Meristem Formation in Arabidopsis and Tomato

2014 ◽  
Vol 26 (5) ◽  
pp. 2068-2079 ◽  
Author(s):  
Quan Wang ◽  
Wouter Kohlen ◽  
Susanne Rossmann ◽  
Teva Vernoux ◽  
Klaus Theres
Keyword(s):  
Leaf Axil ◽  
Axillary Meristem
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