Structure and development of bracteal nectary glands in Aphelandra (Acanthaceae)

A survey of bracteal (extrafloral) nectaries in species of Aphelandra (Acanthaceae) reveals substantial diversity. Each bracteal nectary is an aggregate of individual glands that vary in number, size, and structure among species. Glands contain three cell layers: a palisade-like secretory cell layer, a one-to-many-celled intermediate layer with thickened cell walls, and a foot layer. Members of the A. pulcherrima complex have one of two distinct gland types: relatively small glands with a single-celled intermediate layer or larger glands that have a multicellular intermediate layer. Nectaries composed of small glands are patches of many (>50) glands, whereas those composed of large glands are patches of < 10 glands. Four outgroup species have bracteal nectaries of numerous small glands with pluricellular intermediate layers. Glands of all three types are initiated as single enlarged protodermal cells, and all undergo similar early periclinal divisions; the large-gland type shows greater subsequent enlargement with many more anticlinal divisions. The bracteal nectar glands are interpreted to be homologous with simpler glandular trichomes, and mark a monophyletic lineage within Aphelandra. Comparisons with outgroup species show that both nectary types in the A. pulcherrima complex have diverged from an ancestral condition of numerous small glands with pluricellular intermediate layers. Use of the ontogenetic criterion to polarize gland type within the A. pulcherrima complex would yield erroneous results because evolution has apparently involved a developmental truncation with loss of cell divisions in the intermediate layer of small glands. Comparable nectar glands in more distant taxa are interpreted as remarkable cases of convergent evolution, perhaps from similar trichome precursors.     

New spies and new combinations in Aphelandra (Acanthaceae) from Ecuador and adjacent Peru

Nine new species and a new variety are described: Aphelandra villonacensis from prov. Loja, A. anderssonii from Loja, A. azuayensis from Azuay, A. rumbecensis from Tumbes, Peru, A. zamorensis from Zamora-Chinchipe, A. loxensis from Loja, A. neillii from Zamora-Chinchipe, A. rosulata var. albinotata from Morona-Santiago, A. albinotata from Esmeraldas, and A. mollissima from San Martin, Peru. The new taxa are described, illustrated, and compared with their closest relatives. Two new combinations are made: Aphelandra modesta and A. rosulata .     

The genus Dyschoriste (Acanthaceae) in Bolivia and Argentina

Recent field work in Bolivia has resulted in the recognition of new species ofDyschoriste (Acanthaceae). These novelties are introduced here for the convenience of other taxonomists prior to the publication of a treatment of the Acanthaceae of Bolivia. Three new Bolivian and one new Argentinean species ofDyschoriste,D. axillaris, D. boliviana, D. ceciliae, andD. prostrata are described, illustrated, and compared to their closest relatives.     

Predispersal predation of an understory rainforest herb Aphelandra aurantiaca (Acanthaceae) in gaps and mature forest

The opening of a canopy gap at Los Tuxtlas rainforest has an impact on populations of the understory herb Aphelandra aurantiaca: the ratio of recruited seedlings per reproductive individual is 1:17 in mature forest vs. gaps. Predation occurring before seed dispersal seems a plausible explanation for this observed difference. In a field experiment, in which insecticide was applied to plants growing in gaps and mature forest, we evaluated the extent to which herbivore damage to flowers, fruits, and seeds reduces the number of seeds available for seedling establishment. Under natural conditions, ∼30% of the flowers and >70% of the capsules of A. aurantiaca showed herbivore damage, but its impact changed depending on the type of forest habitat. Flower and fruit herbivores caused more damage in closed forest than in gaps, and this difference was even bigger under the insecticide treatment. Insecticide effectiveness varied depending on the type of forest patch. The highest herbivore impact on seeds was found in the mature forest without insecticide treatment, where most seeds were destroyed. The percentages of seed damage reported here show that predispersal predation is limiting seedling recruitment, especially in mature forest. Other possible explanations might be differences in insect composition, densities, and behavior between gaps and mature forest.     

Wuacanthus (Acanthaceae), a new Chinese endemic genus segregated from Justicia (Acanthaceae)

A new genus, Wuacanthus Y.F. Deng, N.H. Xia & H. Peng (Acanthaceae), is described from the Hengduan Mountains, China. Wuacanthus is based on Wuacanthus microdontus (W.W.Sm.) Y.F. Deng, N.H. Xia & H. Peng, originally published in Justicia and then moved to Mananthes. The new genus is characterized by its shrub habit, strongly 2-lipped corolla, the 2-lobed upper lip, 3-lobed lower lip, 2 stamens, bithecous anthers, parallel thecae with two spurs at the base, 2 ovules in each locule, and the 4-seeded capsule. Phylogenetic analyses show that the new genus belongs to the Pseuderanthemum lineage in tribe Justicieae. Wuacanthus is closely related to Pseuderanthemum but differs from the latter by its shorter corolla tube and two minute spurs at the base of each anther-theca. W. microdontus is assessed with the status EN B2ab (iii) based on the IUCN Red List Categories and Criteria.     

Comparative anatomy, morphology, and molecular phylogenetics of the African genus Satanocrater (Acanthaceae)

? Premise of the study: Anatomical and morphological features of Satanocrater were studied to test hypotheses of xeric adaptations in the genus, which is endemic to arid tropical Africa. These features, together with molecular data, were used to test the phylogenetic placement of Satanocrater within the large plant family Acanthaceae. ? Methods: We undertook a comparative study of four species of Satanocrater. Carbon isotope ratios were generated to test a hypothesis of C(4) photosynthesis. Molecular data from chloroplast (trnG-trnS, trnG-trnR, psbA-trnH) and nuclear (Eif3E) loci were used to test the placement of Satanocrater within Acanthaceae. ? Key results: Anatomical features reflecting xeric adaptations of species of Satanocrater included a thick-walled epidermis, thick cuticle, abundant trichomes and glandular scales, stomata overarched by subsidiary cells, tightly packed mesophyll cells, and well-developed palisade parenchyma on both leaf surfaces. Although two species had enlarged bundle sheath cells, a feature often implicated in C(4) photosynthesis, isotope ratios indicated all species of Satanocrater use the C(3) pathway. Molecular data resolved Satanocrater within tribe Ruellieae with strong support. Within Ruellieae, our data suggest that pollen morphology of Satanocrater may represent an intermediate stage in a transition series. ? Conclusions: Anatomical and morphological features of Satanocrater reflect adaptation to xeric environments and add new information about the biology of xerophytes. Morphological and molecular data place Satanocrater in the tribe Ruellieae with confidence. This study adds to our capacity to test hypotheses of broad evolutionary and ecological interest in a diverse and important family of flowering plants.     

A preliminary analysis of distribution patterns in a large, pantropical genus, Barleria L. (Acanthaceae)

Barleria L. (Acanthaceae) is a large, polymorphic, widespread genus of herbs and shrubs comprising about 300 species, occurring mainly in Africa and Asia but with one species, Barleria oenotheroides Dum.Cours., extending to the New World tropics. Recent completion of a monographic infra-generic classification of the genus (in which seven sections are recognised, and the names of four of these validated in this paper—see Appendix 1), has facilitated a comprehensive analysis of distribution patterns on a global scale. The richest representation of Barleria is in Africa where there are two centres of diversity, one in tropical East Africa (about eighty species) and the other in southern Africa (about seventy species). The number of species tails off rapidly to both the Far East and the West. Barleria shows a marked trans-Atlantic disjunction between West Africa and the Neotropics, with B. oenotheroides shared by these two regions. This type of disjunction, which is known in other genera of the family, cannot be adequately explained in Barleria on the basis of long-distance dispersal or past continental movements. There is a high degree of regional endemism (e.g. 75% for the Indian subcontinent) at both the species and sectional levels within this genus. The degree of similarity between regions is correspondingly low. The endemics in each region tend to belong to only one or a few of the sections. There are few truly widespread taxa within the genus. East and West Africa are the only regions in which all sections are represented. Sections Barleria and Prionitis C.B. Cl. are the most widespread in the genus; Sections Somalia (Oliv.) Lindau, Fissimura M. Balkwill and Stellatohirtae M. Balkwill are mainly restricted to Africa and Sections Chrysothrix M. Balkwill and Cavirostrata M. Balkwill are the most restricted, occurring mainly in India and Sri Lanka. On a local scale, many of the species show highly restricted, clumped distributions; this is apparently related to particular soil types and possibly to the short-distance, ballistic mode of seed dispersal. This account of the biogeography of Barleria is to be regarded as preliminary, as much taxonomic work at the species level remains to be done before a full-scale cladistic biogeographic account can be undertaken. Particular areas worthy of future investigation include establishing the centre of origin of the genus and investigating the basis for the high degree of endemism shown by many of the species.     

国产爵床科鳞花草族1属、穿心莲族2属和爵床族8属植物的花粉形态

报道了中国爵床科Acanthaceae爵床亚科Ruellioideae鳞花草族Lepidagathideae 1属、穿心莲族Andrographideae 2属和爵床族Justicieae 8属共14种植物的花粉形态。根据花粉萌发孔类型和外壁纹饰特征,可将这些植物的花粉归为4个类型: (1)具3孔沟,外壁具网状纹饰。该类型见于色萼花属Chroesthes (采自广西样品)和穿心莲属Andrographis植物。(2)具3孔沟及假沟(肋条带型)类型,外壁具网状纹饰,网眼纵向排列成行,网眼内有细网纹。该类型见于色萼花属(采自云南样品)和鳔冠花属Cystacanthus。(3)具3孔沟,沟两侧各有1条假沟,外壁具网状纹饰。该类型见于瑞丽山壳骨Pseuderanthemum shweliense、狗肝菜属Dicliptera和驳骨草属Gendarussa植物。(4)具2孔沟,沟两侧具斑块。该类型见于山壳骨属Pseuderanthemum 1种、纤穗爵床属Leptostachya、鳄嘴花属Clinacanthus、鸭嘴花属Adhatoda、杜根藤属Calophanoides和野靛棵属Mananthes植物。     

Iridoid glucosides of the genus Veronica s.l. and their systematic significance

 The mode of reproduction, pollen production, chromosome numbers, genetic variation (RAPD, allozymes) and overall similarity were studied in 6 species of Hieracium sect. Alpina in the Tatry Mts. (the Western Carpathians, Slovakia). All species were confirmed to be agamospermous and, except of H. krivanense and H. slovacum, lacking pollen grains. For the first time, a chromosome number is reported for H. krivanense (2n=4x=36). Considerable genetic variation was revealed in H. alpinum and a correlation between geographic and genetic distances was found in this species. Between-population variation in RAPD and allozyme phenotypes was found in H. pinetophilum and H. crassipedipilum. In all other species, allozyme and RAPD variation was low or absent. With few exceptions, the species differ in their allozyme as well as RAPD patterns. The relatedness of one population of endemic H. slovacum and H. halleri was confirmed. It is shown, that Carpathian species of the H. fritzei group are derived from at least two ancestors. Received July 3, 2000; accepted June 24, 2002 Published online: November 20, 2002 Addresses of the authors: H. Štorchová, (e-mail: storchova@ueb.cas.cz) Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 135, CZ-165 00 Praha 6, Czech Republic. I. V. Bartish, J. Chrtek Jr., J. Kirschner, M. Tetera, J. Štěpánek, Institute of Botany, Academy of Sciences of the Czech Republic, CZ-252 43 Pruhonice, Czech Republic.     

Floral structure, development and diversity in Thunbergia (Acanthaceae)

Floral structure and development of 18 species of Thunbergia (Thunbergioideae si , Acanthaceae) were studied comparatively. The flowers of Thunbergia are highly diverse and show a wide range of pollination syndromes. In general they are large and showy. Their pollination apparatus is highly elaborate, floral organs are often synorganized, and floral architecture is complex. In contrast to the high diversity of the anthetic flowers, their bauplan is uniform and their early development shows no major differences, i.e. in all species studied, the calyx arises as a ring primordium, the corolla is 'late sympetalous', and petals and stamens are initiated more or less simultaneously. Some differences are found in further calyx development, where several developmental patterns are present. More significant differences arise only later during development and mainly concern the structures of the calyx, the anthers, the stigma, and corolla aestivation. In the anthetic flowers there are many special characters that are present in all or the majority of the species studied, e.g. the calyx is reduced, the corolla tube is subdivided into two compartments and the anthers lack an endothecium. The present results on development and morphology of the flowers of Thunbergia are compatible with an earlier subdivision of the genus into eight subgenera.     

Synthesis and spectroscopic and fungicidal characterization of hydroxamic acids and their metal chelates

Hydroxamic acid chelates of the type ML2, ML2', and ML2" where M = Cu(II), Ni(II) or Co(II) and L = N,2'-diphenylacetohydroxamic acid (N,2'-DPAHA), L' = 2,2'-diphenylacetohydroxamic acid (2,2'-DPAHA), and L" = 2-phenylacetohydroxamic acid (2-PAHA) have been isolated and characterized on the basis of elemental analysis and infrared and magnetic data. These metal chelates were screened for their fungicidal activity. The testing against fungi has been carried out by slide germination technique against Alternaria alternata and by inhibition zone technique against Fusarium oxysporum and Aspergillus flavus. The fungicidal activity of chelates and their parent ligand has been compared with the commercial fungicide, Dithane M-45, screened under similar conditions.     

Succinimide hydroxamic acids as potent inhibitors of histone deacetylase (HDAC)

A series of succinimide hydroxamic acids was prepared and evaluated in vitro for HDAC inhibition and tumor cell antiproliferation. While the original macrocyclic analogue 6 was quite potent in both assays, several appropriately substituted non-macrocyclic succinimides, such as 23, were equipotent.     

Pranceacanthus coccineus (Acanthaceae), a new genus and species from Amazonian brazil

The new genusPranceacanthus, apparently most closely related to the bitypic genusJuruasia, is described and illustrated. Its sole species,P. coccineus, has been collected on “terra firma” in lowland Amazonian Brazil in the states of Amazonas and Mato Grosso and in the territory of Rondônia.     

New taxa in Anisotes (Acanthaceae)

Diagnoses of three new species and three new subspecies of Anisotes are presented together with those of six subgeneric taxa.     

Taxonomic,nomenclatural, and reproductive notes on Carlowrightia (Acanthaceae)

Information onC. arizonica, C. hapalocarpa, C. mcvaughii, C. parviflora, andC. pectinata published in a monograph of the genus in 1983 is updated. The generic affinities ofC. myriantha andC. sinaloensis are resolved, with the former placed inCarlowrightia and the latter removed to a separate genus. The new combinationC. neesiana, necessitated by conservation of the generic nameCarlowrightia, is provided for the species previously known asC. glandulosa. Two new species from western Mexico,C. fuertensis andC. huicholiana, are described, mapped, and illustrated.