13 research outputs found
Bizonoplast a unique chloroplast in the epidermal cells of microphylls in the shade plant Selaginella Erythropus (Selaginellaceae)
No full textCopyright © 2007 Botanical Society of America, Inc.Chiou-Rong Sheue, Vassilios Sarafis, Ruth Kiew, Ho-Yih Liu, Alexandre Salino, Ling-Long Kuo-Huang, Yuen-Po Yang, Chi-Chu Tsai, Chun-Hung Lin, Jean W. H. Yong and Maurice S. B. K
Leaf Morphology of Selaginella P. Beauv. and its Taxonomic Significance in Taiwan
No full textMicrophyll morphology of 16 Taiwanese species of Selagienlla was observed under light microscopy and scanning electron microscopy. Features studied include microphyll arrangement, epidermal cell morphology, stomal distribution, shape arrangement and distribution silica body on microphyll surface. Microphyll are dimorphic and 4-ranked arrangement, with ventral microphylls larger than the dorsal microphylls. The epidermal cells at dorsal side of dorsal microphylls and at ventral side of ventral microphylls are similar, which are tetragonal or oblong in shape and sinuolate or sinuate in anticlinal cell walls. The epidermis at ventral side of dorsal microphylls and dorsal side of ventral microphylls are similar, which are sub-square or rectangular in shape and straight or sinuolate in anticlinal walls. Stomata are mainly distributed on dorsal side of dorsal microphylls and ventral side of ventral microphylls. Four distribution patterns of are found on microphyll silica body, which are microphyll margin, midrib, homogeneity and nil patterns. Four types of arrangement of silica body on epidermal cells were recognized, namely single row, multi-row, mixed and globulate types. In Taiwan, the characters appeared in epidermal cell morphology and stomal distribution of microphyll are useful for species identification in Selaginella, while those of distribution at patterns and arrangement types of silica bodies on epidermal cells are valuable for the species identification under subgenus
A Taxonomic Study of Carex (Cyperaceae) in Taiwan
No full textThe genus Carex L. (Cyperaceae) contains three subgenera, more than 70 sections, and 1500\ue22500 species in the world. In Taiwan, it includes about 60 species, 3 subgenera, and 26 sections. Identification of the taxa of the genus is relatively difficult, because its reproductive and sexual organs are reduced, and many species are morphologically in similarity. It is therefore necessary to clarify the variation ranges of characters and correct scientific name of each species. This study excludes the section of Praecoces of the subgenus Carex, because it was taxonomically treated 13 years ago. My attempt in this study is to employ macro-morphological characters to solve taxonomic problems for those species in Taiwan. In addition, anatomical characters are also applied in order to explore their possibilities applicable to the whole genus.
Five anatomical characters, including outline shapes of leaf transverse section, shape of adaxial ribs, shape of air-cavities, and numbers of lateral veins, numbers and shape of bulliform cells, were used. Because of lack of fresh materials, only 4 species consisting of C. cruciate, C. filicina, C. rafflesiana and C. satsumensis in the genus Carex have been observed. Those anatomic characters are verified useful.
In this study, taxonomic treatment of 39 taxa (38 species and 1 variety) have been made, except those the section Praecoces. In the treatments, three species, C. caucasia Steven, C. subfilicinoides K\uc3\ubckenthal, C. longistipes Hayata were treated as synonym of C. atrata L., C. filicina Nees, C. fulvorubescens Hayata, respectively; five species, C. fulvorubescens, C. liui Koyama & Chuang, C. morii Hayata, C. purpureotincta Ohwi and C. urelytra Ohwi, were confirmed endemic to Taiwan. The color pictures, line drawings, and distribution maps for 39 taxa were provided
The Comparative Morphology and Anatomy of the Eastern Mangrove Rhizophoraceae
No full textMangroves are a group of the intertidal plants with unrelated phylogenetic affinity distributed in regions of estuaries, riverbanks or along the coastlines of tropical and subtropical areas. The four genera of tribe Rhizophoreae of Rhizophoraceae are important members of mangroves, namely Bruguiera, Ceriops, Kandelia and Rhizophora and also known as mangrove Rhizophoraceae, with a wide distribution range. Fourteen of 17 species of mangrove Rhizophoraceae distributed in the areas between the Eastern Africa to the Pacific West Coast, belong to the eastern mangrove Rhizophoraceae.
Thirteen species of the eastern mangrove Rhizophoraceae from different populations were sampled for the studies in comparative morphology and anatomy on stipules, leaves, flowers, fruits and viviparous seedlings. In contrast, four species of three genera belong to the inland Rhizophoraceae were also sampled. Such works were emphasized on stipules and leaves.
Three kinds of sclereids were found in the stipules of Ceriops and Rhizophora, but none in Kandelia and Bruguiera. Several to hundreds colleters arranging in several series occur at the adaxial base of a stipule in Rhizophoraceae. The aggregated forms, series number, number and individual morphology of colleters are generic or specific, and could be an aid for taxonomic identification. The number and size of colleters found in the mangrove Rhizophoraceae are more and larger than those of the inland species. Additionally, the size of stipule in mangrove Rhizophoraceae is larger than those of the inland Rhizophoraceae. These characters might imply an adaptive selection of stipule and colleters in Rhizophoreae.
In this study, many of the previous discrepancies of leaf anatomical features were clarified. Meanwhile, the plasticity of leaf structure, features of sclereid ideoblasts and crystals were not previously reported. The leaves of mangrove Rhizophoraceae present thick leaves and cuticular wax, sunken and cyclocytic stomata with distinct inner and outer ridges, 2 to 8 cell-layered hypodermis, enlarged terminal tracheids, four types of sclereid ideoblasts and abundant tanniferous cells and drused crystals. All species of the mangrove Rhizophoraceae has potential to produce cork warts on both sides, but only Rhizophora has the warts mainly on abaxial side regularly. Detailed stomatal features could serve as diagnostic character in species level. On the contrary, the inland species has thin leaves with less cuticular wax, superficial anomocytic stomata, no hypodermis and enlarged terminal tracheids, drused and raphid crystals.
The diverse morphological features in flowers and fruits, especially in inflorescences, petals and stamens, provided valuable and reliable taxonomic characteristics. A detailed survey for flower and fruit parts (including the viviparous seedlings) were provided in this study. Some unique and curious phenomenon, including multi-cotyledons to united cotyledon and cotyledon collar, endosperm overflow, the present of coleorhiza in the hypocotyl of Bruguiera, provided interesting and valuable embryological information for the mangrove Rhizophoraceae. Downward and upward orientation seedlings on the mother trees were observed, however the latter were not noticed previously.
Two new taxa were recognized based on many lines of evidences in this study. A new species, Kandelia obovata C. R. Sheue, H. Y. Liu and J. W. H. Yong, which distributed northern from the South China Sea, was named and described. The detailed morphological and anatomical features of Ceriops australis (C. T. White) E. R. Ballment, T. J. Smith III & J. A. Stoddart were firstly described, which confirmed its taxonomic status. A systematic approach with a global view on the mangrove Rhizophoraceae is still needed, especially for Ceriops and Rhizophora
Stipules and colleters of the mangrove Rhizophoraceae: morphology, structure and comparative significance
No full textOne characteristic possessed by the entire mangrove Rhizophoraceae is the strong enclosure
of its young shoots by conspicuous rounded or flattened stipules. Young leaves are conspicuously immersed in
resinous to milky exudates from colleters (multicellular external secretory emergences) located at the adaxial
stipule bases. We systematically studied and compared morphological and structural features of stipules and
their colleters from 18 taxa of the mangrove Rhizophoraceae. Three types of sclereid idioblasts (Ceriops and
Rhizophora), collenchymas, and thick cuticles, were found to provide a structural basis for the mechanical
support of stipules. Several to hundreds (35-580) of finger-like colleters aggregate into genus-specific shapes:
rectangular to trapezoidal (Bruguiera), triangular (Ceriops and Kandelia), or as a band (Rhizophora). Number
of rows, total number of colleters per stipule, and their individual size, also vary by taxon, and have taxonomic
value. All colleters of this subfamily are considered anatomically ‘standard’, regardless of whether they
appear as short-stalked rods (Bruguiera), long-stalked rods (Ceriops, Kandelia) or acuminate rods (Rhizophora,
no stalk). Colleters in these taxa are comprised of a central axis of slender, elongated cells and an outer palisade-
like epidermis, with a secretory function, perpendicular to the axis. Based on stipule and colleter characteristics,
Ceriops and Kandelia are closely related, but Rhizophora shows more derived features. The structural
and mechanical protection provided by stipules and colleter exudates may help shield the young shoots of
these mangrove plants from their harsh environments
The diversity of pistillate flowers and its taxonomic value to the classification of Daphniphyllum (Daphniphyllaceae)
No full textDaphniphyllum is the sole genus of the family Daphniphyllaceae consisting of dioecious species
with inconspicuous reduced unisexual mostly caducous flowers. The paucity of helpful taxonomic characters
from vegetative and reduced reproductive organs has led to difficulties in intrageneric classification
and species identification. The pistillate flowers have characters of higher taxonomic value than those of the
vegetative organs, staminate flowers and fruits, but pistillate flower information is rarely reported. Here pistillate
flowers of 19 taxa were studied to reveal pistillate floral diversity and major developmental features with
a view to intrageneric classification. Four types of stigma shape were recognized: punctiform, reniform, linear
and oblong. Daphniphyllum stigmas, except for the punctiform type, elongate variously after an early stage of
anthesis. The pistillate flowers of three taxa are asepalus. The calyces of other taxa were categorized into three
types, free, cleft and parted, which are consistent within taxa. The existence and persistence of staminodes are
diagnostic characters. This study shows that the characteristics of pistillate flowers provide helpful information
for identification at the species and even the variety level. Our results do not support the currently accepted
two sections, Daphniphyllum and Lunata. Instead, Huang’s original intrageneric classification into three sections,
Daphniphyllum, Lunata and Staminodia, is supported, but with two species previously in Daphniphyllum
reassigned to Staminodia
A MULTILOCUS PHYLOGENY OF GENUS DAPHNIPHYLLUM (DAPHNIPHYLLACEAE)
No full textTable S1: Sampling information and GenBank accession numbers of the studied Daphniphyllum plants and outgroups. Table S2: The primers and amplification protocols applied in this study. File S3: the cp (psbA-trnH spacer + trnL intron) alignments and trees. File S4: the ITS alignments and trees. File S5: the hypothesis tree (Ho) and constraint ML tree for the topological conflict analyses using cp alignment. File S6: the hypothesis tree (Ho) and constraint ML tree for the topological conflict analyses using ITS alignment. Table S7: List of the Daphniphyllum herbarium samples. Figure S8. Bayesian inference (BI) of Daphniphyllum based on the ITS+cp combined alignment with a length of 1602-bp and 127 indels. Note that natural hybrid taxa are removed. Numbers after taxa refer to Table S1. Numbers at nodes show Bayesian posterior probabilities / ML bootstrap values only when posterior probability is > 0.70 or bootstrap value is > 50. The arrow shows the crown node of Daphniphyllum. Clades are indicated as Fig. 2.</p
Molecular phylogeny and evidence for natural hybridization and historical introgression between Ceriops species (Rhizophoraceae)
No full textCeriops (Rhizophoraceae) is a genus comprised of five species of mangroves distributed in
tropical and subtropical coastal regions. In this study, sequences from nuclear ribosomal ITS
and the plastid trnL intron are used to construct molecular phylogenies of this genus
revealing two species complexes, the C. tagal complex (C. tagal and C. australis), and the
C. decandra complex (C. decandra, C. pseudodecandra and C. zippeliana), each forming
a distinct clade. All five species, including the newly designated species C. pseudodecandra,
are well supported. However, natural hybridization and historical introgression between
Ceriops species are also demonstrated. The ITS sequences of Ceriops species, in contrast to
their plastid trnL intron sequences, show a great amount of homoplasy during evolution.
Historical introgression originating from natural hybridization was demonstrated based on
the additivity of ITS sequences from putative parents. Of the five Ceriops species, C. pseudodecandra
is a relatively isolated species. C. decandra and C. zippeliana show mutual
introgression in most populations. According to both the nuclear ITS sequences and the
plastid trnL intron, an intermediate form from Darwin is likely a natural hybrid, with C. tagal
and C. australis respectively the maternal and paternal parents
Reevaluating the taxonomic status of Ceriops australis (Rhizophoraceae) based on morphological and molecular evidence
No full textCeriops australis (White) Ballment, Smith & Stoddart, a member of the mangrove family Rhizophoraceae, was originally recognized as C. tagal var. australis White but was raised to species rank based solely on isozyme features and the only distinctive morphological feature of the hypocotyl. Therefore, it was considered a sibling species of C. tagal (Perr.) C. B. Rob. The goal of this study was to test the previous assessment that C. australis and C. tagal differ consistently only in hypocotyl morphology, in order to reevaluate the taxonomic status and to establish its geographic range. Principal components analysis was employed to analyze 29 morphological characters of herbarium specimens from Australia, Madagascar, and Sumatra tentatively identified as C. australis and C. tagal, and two well differentiated distinct taxa were recognized. In addition, both of the detailed morphological features based on fresh and herbarium materials and the intron sequences of trnL gene from plastid DNA support this conclusion. This finding disagrees with previous assessment and supports the current taxonomic status of C. australis. Here, a key to these two species is provided, and a revised distribution range of C. australis is established. This is the initial report of C. australis’ occurrence in a part of Indonesia, in addition to areas of Australia and Papua New Guinea
