Tag: Baas P.

Diversity of stomatal type in the Linaceae

 

 

A leaf anatomical contribution to the classification of the Linaceae complex

by Van Welzen P. C., Baas P. (1984)

in Blumea 29(2): 453–479 –

Google Scholar – 

https://geoscience.net/research/004/580/004580238.php

Abstract

The leaf anatomy of the Linaceae complex (Linaceae s.s., Hugoniaceae, Ixonanthaceae, Humiriaceae and Erythroxylaceae) and putative allies (Ctenolophon, Lepidobotrys, Irvingiaceae) is surveyed.

Mostly on the basis of original observations (72 specimens, 27 genera), partly from data in the literature.

Diversity of stomatal type, midrib and petiole vascularization, sclerenchyma support, foliar sclereids, mucilage cells, secretory cavities, and cristarque cells provide evidence in favor of a separate family status of the members of the Linaceae complex.

Allantospermum and Cyrillopsis are best acommodated in the Ixonanthacea. Irvingiaceae (often treated in or near Simaroubaceae) show similarities with the Linaceae complex, although more closely to the Hugoniaceae than to the Ixonanthaceae to which they have been transferred by some authors.

Ctenolophon seems unrelated, but leaf anatomy gives no strong clues for its true affinities. Lepidobotrys may be related to the Linaceae complex, but its leaf anatomy is also in good agreement with treatment in or near the Oxalidaceae. Within the Ixonanthaceae, Phyllocosmus deserves generic status next to Ochthocosmus due to the exclusive occurrence of tracheoidal idioblasts in the latter and lack of them in the former.

The results are discussed in connection with evidence from other sources of enquiry.

Stomata and classification of the Olacaceae

 

 

Leaf anatomy and classification of the Olacaceae, Octoknema, and Erythmpalum

by Baas P., van Oosterhoud E., Scholtes C. J. L., (1982)

Rihjksherbarium Leiden, The Netherlands

in Allertonia 3: 155–210 –

Google Scholar – 

http://www.jstor.org/stable/23192277?seq=1#page_scan_tab_contents

Abstract

The leaf anatomy of all genera of Olacaceae and of Erythropalum and Octoknema is described in detail, and a key to genera is provided. The Olacaceae show an estraordinary amount of leaf anatomical diversity which lends itself well for classification purposes.
Decisive characters of taxonomic significance are: secretory cavities; laticifers; silicified mesophyll cells; vascular system of petiole and midrib; supporting sclerenchyma fibres and brachy-astrosclereids in petiole and midrib; stomatal type; lignification of guard cells; position of lumina in the guard cells and development of outer cuticular ledges; crystalliferous development.
Varying characters such as occurrence and type of mesophyll sclereids, occurrence of silica bodies, and various crystal complements are of more restricted taxonomic value (i.e., mostly below the genus level). Based on different combinations of characters, nine groups can be distinguished. Two of these are represented by the single genera Erythropalum and Octoknema, which take isolated positions within the family, or for which family status (Erythropalaceae and Octoknemaceae) could be advocated. The other seven groups can be arranged in a system reflecting phylogenetic relationships. These groups show a fair degree of correlation with the traditional tribes recognised on macromorphological and ovule characters: Group I coincides with the tribe Couleae; Group II consists of the single genus Heisteria; Group III consists of Chaunochiton; Group IV comprises the tribes Aptandreae, Olaceae, and Ximenieae, as well as the genera Schoepfia, Malania, and Douradoa; Group V consists of Anacolosa, Phanerodiscus, and Cathedra, previously forming part of the Anacoloseae; Group VI, Scorodocarpus and Brachynema, was formerly also part of Anacoloseae, as well as Group VII, consisting of Strombosia, Strombosiopsis, Tetrastylidium, and Diogoa. The main new elements of this grouping are: the abolishment of subfamily boundaries; the artificial nature of the tribe Anacoloseae (group V is not closely related to groups VI and VII but rather to group IV); and the close links of Chaunochiton with groups IV and V rather than with Heisteria, with which it was formerly treated in the same tribe, the Heisterieae. The phylogenetic reconstruction of the Olacaceae based on cladistic methods is discussed in relation to data from wood anatomy, pollen, and ovule morphology and parasitism in the family. The specialised groups of the Olaceceae are clearly related to other santalalean families, notably Santalaceae, Loranthaceae, Misodendraceae, and Opiliaceae. The Olacaceae are a basic family within the Santalales, of which the wider affinities cannot be unambiguously established by leaf anatomy, but traditionally advocated links was Celastrales can be supported. On account of the pantropical, transpacific, or transatlantic distribution of most of the leaf anatomically recognised groups, it is argued that they must have differentiated before the breaking up of Gondwanaland, and that many of the leaf anatomical characters of individual Olacaceae are very conservative and date back to Cretaceous times.

Stomata in Heisteria (Olacaceae)

Photo credit: Google

Heisteria cauliflora

 

Screen Shot 2017-10-01 at 14.06.29

Fig. 1. Heisteria scandens. Paradermal section. Paracytic stomata and undulating anticlinal epidermal cell walls, x 340. — 2. H. asplundii. Paradermal section. Laterocytic stomata, x 340. — 3. H. maytenioides. Maceration. Thick anticlinal walls. Stomata (below level of leaf surface) mostly anisocytic, x 340. — 4. H. silvianii. Maceration. Stomata anomocytic, cyclocytic, anisocytic and intermediate, x 340. — 5. H. zimmereri. Transverse section of midrib with simple, closed vascular system, x 55. — 6. H. cauliflora. Ibid., complex vascular system with additional adaxial bundle (arrow), x 55.

Comparative leaf anatomy of Heisteria (Olacaceae)

by Baas P., Kool R. (1983)

Rijksherbarium Leiden, The Netherlands

in Blumea 28:367–388 –

Google Scholar – 

http://repository.naturalis.nl/document/565018

Summary

The leaf anatomy of all 33 species of Heisteria is described, based on a study of 143 specimens. There is a considerable amount of diversity in stomatal type (anisocytic, anomocytic, cyclocytic, laterocytic or paracytic), in occurrence and type of mesophyll sclereids, and of fibre bundles along the leaf margin.

Outline and thickness of anticlinal epidermal cell walls, cuticle thickness, crystal complement, and stomatal size also vary, but often below the species level.

The leaf anatomical diversity can be used for recognising 8 groups of varying distinctness in Heisteria. H. asplundii and H. skutchii with laterocytic stomata, and H. pentandra and H. scandens with paracytic stomata constitute the two most distinct infrageneric groups; the other six groups appear mutually more closely related and are partly linked through intermediates.

A tentative phylogenetic classification of Heisteria and a discussion of the position of Heisteria in the Olacaceae is given.

Stomata in the Asiatic Myristicaceae

Photo credit: Google

Fruit of Knema globularia

 

Comparative leaf anatomy of the Asiatic Myristicaceae

by Koster J., Baas P. (1981)

Rijksherbarium Leiden, The Netherlands

in Blumea 27: 115–173 –

Google Scholar – 

http://repository.naturalis.nl/document/565506

The stomatal complex (photos 13, 23—27)

Stomata are confined to the abaxial epidermis; however, in Gymnacranthera bancana var. borneensis a very small number is also present in the adaxial epidermis. They are randomly distributed, abundant on the areolae, scanty on the midrib, the veins and along the leaf margin. If they are present here, the stomatal complex shows abnormalities.

Several authors have pointed out that the stomatal index may be extremely variable within a species (Bongers, 1973; Jansen & Baas, 1973; Van Staveren & Baas, 1973). Stomatal indices have therefore not been determined in this study.

The stomatal type of the species examined is paracytic (photo 27). The dimensions of the guard cell pairs range from 8 to 21 mu for the width and from 15 to 39 mu for the length. The genera have a different size range (in Myristica relatively long stomata and in Gymnacranthera and Knema relatively short stomata are present), but a large overlap occurs.

Screen Shot 2017-09-07 at 21.19.32

The variation in one single leaf can be up to 8 and 12 mu for the width and length respectively. However, the average values show fairly little variation in a genus. Therefore, the data for the stomatal sizes per specimen are not given in tables.

Giant or water stomata have been recorded for some specimens of Gymnacranthera contracta and Gymnacranthera forbesii var. forbesii only. The guard cells are often embedded in the subsidiary cells, most conspicuously in Gymnacranthera and Knema; here, in a section perpendicular to the pore, the subsidiary cells fully enclose the guard cells, the poral sides excepted (photo 24).

Screen Shot 2017-09-07 at 21.21.36

In Gymnacranthera such sections also show pointed, sometimes protruding subsidiary cells, whereas the unspecialized epidermal cells are lowly dome-shaped or square to rectangular. Outer stomatal ledges are fairly well developed in some species of Horsfieldia only.

A peculiar character is formed by the cells surrounding the stomatal complex in Knema and Myristica. In the cuticular macerations and the free hand sections of the Knema species the stomatal complex itself is difficult to observe, lying on a lower level than the other epidermal cells.

A star-shaped opening, left by 4 to 6 epidermal cells overarching the stomatal complex, indicates the position of the stoma (photo 23). The transverse sections show the strongly sunken stomatal complex with a thin cuticle, overarched by more or less horizontally directed papillae of the bordering epidermal cells (photo 24); these nipple-shaped papillae give the star its characteristic form.

Siddiqi and Wilson (1975c) proposed that the ‘star-shaped structure’ is formed by hypodermal cells. This appears to be incorrect. In Myristica the sunken stomatal complex is partly overarched by more or less upright papillae of the 4 to 11 bordering epidermal cells (photo 26). In surface view these papillae, varying in height per species, form a ring above the stomatal complex (photo 13,25). As stated elsewhere, the unspecialized epidermal cells in most species are without papillae.

Screen Shot 2017-09-07 at 21.15.34

Screen Shot 2017-09-07 at 21.23.48

Screen Shot 2017-09-07 at 21.17.40

Stomata in the Malesian Icacinaceae

 

 

Epidermal leaf characters of the Malesian Icacinaceae

by Van Staveren M. G. C., Baas P. (1973)

Rijksherbarium Leiden, The Netherlands

in Acta Botanica Neerlandica,  22(4): 329–359 – https://doi.org/10.1111/j.1438-8677.1973.tb00851.x

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1438-8677.1973.tb00851.x

 

Scan

Scan 1

Scan 2

Stomata in Kokoona and Lophopetalum (Celastraceae)

 

Photo credit : Google

Kokoona zeylanica

Comparative leaf anatomy of Kokoona and Lophopetalum (Celastraceae)

by Jansen W. T., Baas P. (1973)

Rijksherbarium Leiden

in Blumea 21: 153-178

C5kB7XaUwAAh17s
Lophopetalum wightianum Arn. -(Celastraceae)  – https://pbs.twimg.com/media/C5kB7XaUwAAh17s.jpg

Scan

Scan 1

Scan 2

The epidermis in Icacinaceae (dicots)

EPIDERMAL LEAF CHARACTERS OF THE MALESIAN ICACINACEAE

by Van Staveren M. G. C., Baas P. (1973)

in Acta Botanica Neerlandica, Volume 22, Issue 4, 329–359, August 1973

SUMMARY

The cuticular characters of the leaves of all Malesian species belonging to 25 genera of the Icacinaceae and those of Pennantia from Australia and New Zealand and some taxa from Continental Asia have been studied and are described in detail.

Five stomatal types and nine different hair types are recorded for this part of the family. Haberlandt’s interpretation of the slender papilla-like hairs of Gonocaryum as hydathodes is challenged. Penetrating asteroscleroids in the cuticular flanges of two Stemonurus species are reported for this family for the first time.

A synoptical key to the genera on the basis of cuticular characters only is given. The diagnostic and taxonomic value of the characters used is discussed.

 

Taxonomic implications of this study are the indication of a close relationship between Phytocreneae and Iodeae (all climbers), the isolated position of the genera Platea and Gonocaryum, and the impression that Mappianthus should be treated as a genus separate from Iodes.

 

The combined characters of indumentum and stomatal type do not show an absolute correlation with the levels of specialization found in wood- and nodal anatomy for this family by Bailey and Howard.

The distribution of stomatal types over the genera, however, suggests that the paracytic and anomocytic types are primitive for Icacinaceae and that the cyclocytic and anisocytic types are more derived.

Stomata in Celastraceae (dicots)

EPIDERMAL CHARACTERS OF THE CELASTRACEAE SENSU LATO

by Den Hartog R. M.  née Van Ter Tholen, Baas P. (1978)

in Acta Botanica Neerlandica, Volume 27, Issue 5-6, pages 355–388, December 1978

SUMMARY

The leaf epidermal characters of 89 species belonging to 42 genera of the Celastraceae sensu lato (including Hippocrateaceae) are described in detail. The range and pattern of variation in stomatal type and presence and type of crystalliferous epidermal cells can be used to support the broad family concept of Celastraceae.

 

The stomata may be anisocytic, complex anisocytic, anomocytic, cyclocytic, bi- and/or tricyclic, complex cyclocytic, laterocytic, complex laterocytic, paracytic, parallelocytic, helicocytic, or of an intermediate type. The laterocytic stomata are most common, and are here recognized for the first time as a distinct stomatal type characterized by the lateral position of the subsidiary cells (3 or more) but yet different from the paracytic and cyclocytic type.

 

The general implications of the epidermal diversity for the grouping of genera in a natural classification are discussed. Special attention is devoted to the taxonomic position and/or delimitation of the following genera: Kokoona and Lophopetalum; Sarawakodendron; Perrottetia; Salada and the related genera Cheiloclinium, Peritassaand Tontelea; Hippocratea and the putatively related genera Antodon, Apodostigma, Cuervea, Elachyptera, Helictonema, Hemiangium, Hylenea, Loeseneriella, Prionostemma, Pristimera, Reissantia and Simirestis; Cassine sensu lato (including Elaeodendron, Crocoxylon and Mystroxylon); Denhamia and Maytenus; Euonymus; Goupia; Siphonodon and Pottingeria. Finally a tentative discussion of the wider affinities of Celastraceae is given and the scope for future studies is indicated.