Interpetiolar Stipules Research Articles

Flora of Espírito Santo: Hiraeoide and Malpighioide clades (Malpighiaceae)

Abstract This is a taxonomic treatment of four genera and eight species of the hiraeoide and malpighioide clades (Malpighiaceae) in the state of Espírito Santo, Brazil. Hiraea and Mascagnia are the most diverse genera, with three species each, followed by Amorimia and Lophopterys, with one species each. Two species are listed as threatened: H. bullata and M. velutina. The main characteristics that can be used to identify the genera in Espírito Santo are epipetiolar or interpetiolar stipules, the indumentum on the branches, the inflorescence type, the number of elaiophores, and characteristics of the mericarps. Morphological descriptions, identification keys, taxonomic notes, geographic distribution maps, and photographic plates are provided for the species.

Evidence on vegetative and inflorescence morphology of Chloranthaceae (Angiospermae) from the Early Cretaceous (middle–late Albian) of Spain

The near-basal angiosperm family Chloranthaceae (with four living genera) is prominently represented in the Early Cretaceous fossil record by pollen and flowers, but its leaves, other vegetative parts and inflorescences are less well known. Here, we report impressions of leaves, stems and inflorescences from the middle–late Albian Escucha Formation of Teruel Province (NE Spain) that help redress this imbalance and bring into clearer focus the morphological and systematic diversity of this key group in the early angiosperm radiation. We used parsimony analysis of a morphological dataset of living and fossil Chloranthaceae to evaluate the position of the fossils on a molecular-based tree of extant taxa. Todziaphyllum elongatum gen. et sp. nov., with festooned semicraspedodromous venation and asymmetrical chloranthoid teeth, is most parsimoniously placed on the stem lineage of the living genus Hedyosmum. Leaves of Alcainea eklundiae gen. et sp. nov., with festooned semicraspedodromous venation and symmetric teeth, occur attached to stems in opposite pairs at swollen nodes with sheathing leaf bases and interpetiolar stipules, along with compound spikes of flowers with a monosymmetric androecium of three stamens, each flower subtended by a bract. This represents the first time that fossil leaves, stems and inflorescences of Chloranthaceae have been found in organic connection. Alcainea may be sister to Sarcandra, Chloranthus or the clade consisting of both genera, like the mesofossil Canrightiopsis. Leaf Type A, with festooned craspedodromous venation and symmetrical teeth, may be related to Ascarina. These observations provide direct evidence for the distinctive vegetative and inflorescence morphology of Chloranthaceae in the Early Cretaceous. They are consistent with the level of diversification inferred from coeval chloranthaceous pollen and floral mesofossils, including lines nested in crown group Chloranthaceae but not in any of living genera, and exhibiting character combinations not retained in living Chloranthaceae. http://zoobank.org/urn:lsid:zoobank.org:pub:08B96BA0-3B27-48A1-9E8F-CB5811AE8C07

Phylogeny, character evolution and spatiotemporal diversification of the species-rich and world-wide distributed tribe Rubieae (Rubiaceae).

The Rubiaceae tribe Rubieae has a world-wide distribution with up to 1,000 species. These collectively exhibit an enormous ecological and morphological diversity, making Rubieae an excellent group for macro- and microevolutionary studies. Previous molecular phylogenetic analyses used only a limited sampling within the tribe or missed lineages crucial for understanding character evolution in this group. Here, we analyze sequences from two plastid spacer regions as well as morphological and biogeographic data from an extensive and evenly distributed sampling to establish a sound phylogenetic framework. This framework serves as a basis for our investigation of the evolution of important morphological characters and the biogeographic history of the Rubieae. The tribe includes three major clades, the Kelloggiinae Clade (Kelloggia), the Rubiinae Clade (Didymaea, Rubia) and the most species-rich Galiinae Clade (Asperula, Callipeltis, Crucianella, Cruciata, Galium, Mericarpaea, Phuopsis, Sherardia, Valantia). Within the Galiinae Clade, the largest genera Galium and Asperula are para- and polyphyletic, respectively. Smaller clades, however, usually correspond to currently recognized taxa (small genera or sections within genera), which may be used as starting points for a refined classification in this clade. Life-form (perennial versus annual), flower shape (long versus short corolla tube) and fruit characters (dry versus fleshy, with or without uncinate hairs) are highly homoplasious and have changed multiple times independently. Inference on the evolution of leaf whorls, a characteristic feature of the tribe, is sensitive to model choice. Multi-parted leaf whorls appear to have originated from opposite leaves with two small interpetiolar stipules that are subsequently enlarged and increased in number. Early diversification of Rubieae probably started during the Miocene in western Eurasia. Disjunctions between the Old and the New World possibly are due to connections via a North Atlantic land bridge. Diversification of the Galiineae Clade started later in the Miocene, probably in the Mediterranean, from where lineages reached, often multiple times, Africa, eastern Asia and further on the Americas and Australia.

Stipules in Apocynaceae: an ontogenetic perspective.

Stipules are leaf structures common in many groups of plants that can take a variety of forms. In Gentianales, interpetiolar stipules are considered a synapomorphy of Rubiaceae; however, some reports in the literature refer to their presence in other families. The goal of this study was to analyze the development of leaf primordia to investigate the possible presence of reduced or modified stipules in Apocynaceae. Shoot apices of 12 genera were analyzed under light and scanning electron microscopy comparatively with one species of Rubiaceae. Early in their development, leaf primordia form two lateral expansions at the base of the petiole (stipules) that give rise to colleters in 11 of the 12 genera of Apocynaceae studied, similarly to the Rubiaceae species. The basal genera have pairs of stipules modified into colleters positioned laterally to the petiole, while other species belonging to the derived subfamilies have interpetiolar stipules that each project towards the opposite stipule and merge, forming a sheathing stipule and from this arc the interpetiolar colleters originate. The ontogenetic study proved for the first time that Apocynaceae is a stipulate family whose stipules are modified into colleters and their absence might be a secondary loss, changing the interpretation of stipule evolution in Gentianales.

Rubiacearum Americanarum Magna Hama Pars XXXI: More New Neotropical Species and Morphological Notes forPsychotria(Psychotrieae)

Botanical exploration has documented 11 new species of Psychotria L. (i.e., Psychotria s. str., Psychotria subg. Psychotria: Rubiaceae) in the western Amazon basin and Andes of South America. Psychotria anisophylla C. M. Taylor is found at 200–800 m in Peru and Bolivia and is characterized by its unequally sized leaves, calyptrate stipules, and flowers that are solitary or paired and borne on axillary short-shoots. Psychotria awa C. M. Taylor is found at 100–1325 m along the Colombia–Ecuador border and differs from P. hammelii Dwyer in its planar (non-bulliform) leaves. Psychotria calyptrata C. M. Taylor is found at 1021–2850 m in Bolivia and Peru and differs from P. trichotoma M. Martens & Galeotti in its pubescent smaller leaves, subsessile flowers, and fruits that are not stipitate. Psychotria cochabambana C. M. Taylor is found at 1940–2180 m in central Bolivia and differs from P. cutucuana C. M. Taylor by its longer corollas. Psychotria davidsmithiana C. M. Taylor is found at 1600–2862 m in Peru and Bolivia and differs from P. aristeguietae Steyerm. in its shorter calyx lobes. Psychotria diminuta C. M. Taylor is found at 1600–1800 m in Peru and differs from P. parvifolia Benth. by its subsessile leaves with sacciform domatia, 3-flowered inflorescences, and 5-merous flowers. Psychotria grahamii C. M. Taylor is found at 250–850 m in central Peru and differs from P. juninensis Standl. in its longer calyx limbs. Psychotria maynasana C. M. Taylor is found at 120–170 m in Peru and western Brazil and differs from P. anceps Kunth in its larger fruits. Psychotria ortiziana C. M. Taylor is found at 193–900 m in Peru, western Brazil, and Bolivia and is characterized by its bilobed interpetiolar stipules, leaves with sacciform domatia, rather large corollas, and fruits borne on well-developed stipes. Psychotria pandoana C. M. Taylor is found in at 110–285 m in western Brazil and northern Bolivia and differs from P. pectinata Steyerm. in its broader pubescent leaves without domatia and larger corollas. Also, P. sopkinii C. M. Taylor is found at 1500–2730 m in western Colombia and differs from P. convergens C. M. Taylor by its shorter corollas.

Espécies arbóreo-arbustivas da família Rubiaceae Juss. na bacia do rio Tibagi, PR, Brasil

RESUMO Rubiaceae, a quarta maior família de angiospermas em número de espécies no mundo, é reconhecida pelas folhas opostas, estípulas interpeciolares, corola gamopétala e ovário ínfero. Apesar de estar bem representada nas coleções dos herbários, não tem sido completamente estudada no Estado do Paraná. A bacia do rio Tibagi, localizada no centro-leste do Estado, abrange 13% de sua superfície. É dividida em três regiões: Alto, Médio e Baixo Tibagi. Foram analisadas 1.053 exsicatas, provenientes dos acervos de herbários do Estado do Paraná e de coletas de campo realizadas em municípios da bacia. Neste estudo foram registrados 18 gêneros e 35 espécies, onde Psychotria é o gênero com maior riqueza. As espécies Psychotria subtriflora, Psychotria tenuifolia e Simira corumbensis foram apontadas como novas ocorrências para o Estado do Paraná e Psychotria fractistipula, como nova citação para o Estado. Este trabalho amplia os conhecimentos taxonômicos sobre a família Rubiaceae para a flora da bacia do Tibagi e Estado do Paraná.

Euphorbia rayturneri(Euphorbiaceae), a New Species from Southwestern New Mexico, United States

Euphorbia rayturneri V. W. Steinm. & Jercinovic (Euphorbiaceae), a new species endemic to southwestern New Mexico, United States, is described and illustrated. This summer annual occurs in desert grassland and is known from three collections made in Grant, Hidalgo, and Luna counties at elevations of 1400–1700 m. Given its limited distribution and small population size, we propose that the species is best considered as CR, or Critically Endangered, according to IUCN Red List criteria. The new species belongs to Euphorbia L. sect. Anisophyllum Roep. on the basis of possessing interpetiolar stipules and opposite leaves that are asymmetrical at the base. It is characterized by being a pubescent, prostrate herb with serrulate leaves that often have a red blotch in the center and an ovary with undivided styles.

Pharmacognostical studies on the leaves of <i>Ophiorrhiza mungos</i> Linn. (Rubiaceae)

AIM: The aim of the study was to carry out pharmacognostical investigation including macro-, microscopical studies, macerate studies and powder analysis in addition to (high performance thin layer chromatography) HPTLC profile of the leaves of Ophiorrhiza mungos. METHODS: Leaves of O. mungos were collected from the forests of Thenmalai, Kerala and shade dried. A few pieces of the leaf were preserved in 70 % alcohol for pharmacognostical evaluation. Preliminary phytochemical analysis and HPTLC of aqueous and alcohol extracts were carried out and camptothecin was identified by comparing the Rf values. RESULTS: O. mungos is identified by characters like the presence of interpetiolar stipules, gamopetalous corolla and inferior ovary. The leaf drug is identified by the presence of rubiaceous stomata, septate, multicellular trichomes containing crystal sand inclusion, resinous content in cells of ground tissue, vessels with spiral and pitted thickenings which serve as useful pharmacopoeial parameters. Preliminary phytochemical analysis revealed alkaloids, carbohydrates and glycosides, phytosterols, phenolic compounds, tannins and flavonoids in alcohol extract. Aqueous extract contained alkaloids, carbohydrates and glycosides, phenolic compounds, tannins, flavonoids, gums and mucilage. Petroleum ether extract contained phytosterols, fixed oils and fats. Chloroform extract contained alkaloids whereas acetone extract contained phytosterols. HPTLC indicated the presence of camptothecin in alcohol and aqueous extracts. CONCLUSION: It is concluded that these pharmacognostical investigations comprising macro-, microscopical, phytochemical studies including HPTLC profile help in the identification of the leaf drug of O. mungos besides confirming that the alcohol and aqueous extracts contained camptothecin, an useful anticancer agent.

Pisum sativum wild-type and mutant stipules and those induced by an auxin transport inhibitor demonstrate the entire diversity of laminated stipules observed in angiosperms.

About a quarter of angiosperm species are stipulate. They produce stipule pairs at stem nodes in association with leaves. Stipule morphology is treated as a species-specific characteristic. Many species bear stipules as laminated organs in a variety of configurations, including laterally free large foliaceous, small, or wholly leaf-like stipules, and as fused intrapetiolar, opposite, ochreate or interpetiolar stipules. In Pisum sativum, the wild-type and stipule-reduced and cochleata mutants are known to form free large, small, and leaf-like stipules, respectively. Auxin controls initiation and development of plant organs and perturbations in its availability and distribution in the meristems, caused by auxin transport inhibitor(s) (ATIs), lead to aberrations in leaf development. The effect(s) of ATI(s) on stipule development are unexplored. To study the effect of the ATI 1-N-naphthylphthalamic acid (NPA) on stipule morphogenesis, P. sativum explants were grown in vitro in presence of a sublethal concentration of NPA. The NPA-treated shoots produced fused stipules of all the different types described in angiosperms. The observations indicate that (a) the gene sets for stipule differentiation may be common in angiosperms and (b) the interspecies stipule architectural differences are due to mutations, affecting gene expression or activity that got selected in the course of evolution.

Elatine rotundifolia sp. nov. (Elatinaceae) from Ecuador

Elatine rotundifolia sp. nov. is described from tropical and subtropical areas of Ecuador ca 500 m and ca 1800 m a.s.l. All other species in north Andes are from altitudes above ca 3000 m a.s.l. The new species has unilocular capsules and extremely reduced interpetiolar stipules.

A new species of Coprosma (Rubiaceae) from the South Island, New Zealand

A new species, Coprosma fowerakeri, is described from alpine habitats of the South Island, New Zealand. Previously included within C. pseudocuneata, it is distinguished by its low spreading habit; stout, recurved lateral branches that often root on contact with soil; fleshy‐coriaceous, almost succulent, dark green to bronze‐green leaves; conspicuously denticulate, shortly sheathing interpetiolar stipules; bright orange fruit; tetraploid chromosome number; and preference for alpine habitats. Coprosma fowerakeri is an abundant alpine and occasionally subalpine species whose conservation status is rated as “Not Threatened” using the New Zealand Threatened Species Classification System.

Morphological Evidence for an Extended Tribe ‐ Coccocypseleae (Rubiaceae‐Rubioideae)

Abstract: Coccocypselum is a small neotropical genus of creeping herbs belonging to the Rubiaceae (Rubioideae). A recent macromolecular study suggested a previously unknown relationship between Coccocypselum and two other neotropical genera, Declieuxia and Hindsia, but the morphological evidence for this relationship was obscure. In the present paper, morphological characters supporting the conclusions from macromolecular data are presented. The most important similarities between Coccocypselum, Declieuxia, and Hindsia are found in their pollen and stipule morphology. Pollen of the three genera share a typical exine ornamentation, called a complex reticulum, which consists of a psilate suprareticulum and spinulate infrareticulum. In some specimens of Hindsia longiflora, a transitional stage between a complex reticulum and a simple, spinulate reticulum is encountered. The interpetiolar stipules of Hindsia, Declieuxia and Coccocypselum have an identical basic structure: they bear a central, colleter‐tipped awn that extends downwards to the next node as a distinct stem ridge. Some less conspicuous similarities of habit, calyx, and corolla are also discussed. The morphological data are, in part, confirmed by distributional data, Declieuxia and Hindsia having a remarkably congruent centre of diversity in the southeast of Brazil. It is concluded that the macromolecular data, combined with this new morphological and distributional evidence, justify an extended tribe Coccocypseleae, comprising the genera Coccocypselum, Hindsia, and Declieuxia.

Plastid rbcL Sequence Data Show Dialypetalanthus to Be a Member of Rubiaceae

Dialypetalanthus fuscescens Kuhlm., endemic to Amazonia, has been treated as the sole member of Dialypetalanthaceae Rizzini & Occhioni. Various affinities have been suggested, but its phylogenetic position has remained unclear due to the unique combination of characters indicating an affinity with Rubiaceae (e.g. opposite leaves, interpetiolar stipules and an inferior ovary), in which family it was originally placed, or Myrtales (free petals and numerous stamens). Analysis of rbcL sequence data indicates that Dialypetalanthus is a member of Rubiaceae sensu stricto and falls in Ixoroideae sensu lato sensu Bremer with relatively strong bootstrap support (83%). Within the subfamily, Dialypetalanthus falls with a group of other neotropical taxa, but this position is not well supported. In the successively weighted trees Dialypetalanthus fell in a clade with the New World taxa Calycophyllum, Capirona, Condaminea, Hippotis, Pentagonia and Pogonopus. However, this clade received bootstrap support of <50%. On the basis of these data we recommend inclusion of Dialypetalanthus in Rubiaceae, but data for other loci and further morphological analysis will be required before its exact relationships can be determined.

Polymerous Leaf Whorls in Vascular Plants: Developmental Morphology and Fuzziness of Organ Identities.

In vascular plants there are at least eight ways to develop polymerous whorls, i.e., whorls with four or more leaves. Six ways are presented and compared with literature to estimate organ identity (morphological significance) of the leaflike whorl members. New shoots (also seedlings) may start with dimerous or trimerous whorls. Then leaf number per whorl rises as follows: (1) Many taxa add more leaves per whorl continuously with increasing size of the apical meristem (e.g., Equisetum, Hippuris). (2) Taxa provided with interpetiolar stipules replace their stipules by leaves (e.g., Galium and allies). (3) Taxa with the capacity to form compound leaves shift basal leaflets around the whole node (e.g., Limnophila, probably also Ceratophyllum). Various whorled plants start shoot development with leaf inception along a helix, which is continued into the whorled region. Then polymerous whorls develop as follows: (4) Acacia longipedunculata forms helically arranged fascicles instead of single leaves before the production of complete whorls. (5) Acacia baueri and Acacia verticillata add supernumerary leaves between a first series of helically arranged leaves. (6) Hydrothrix produces an annular bulge around the node of each first-formed leaf. All additional leaves of a whorl arise on this annular bulge. Leaf identity of whorl members cannot be defined unequivocally in whorls with asynchronous (i.e., nonsimultaneous) development, dorsoventral distribution of lateral buds, and/or fewer vascular traces than leaves per node. It is heuristically stimulating to accept structural categories (e.g., shoot, leaf, leaflet, stipule) as fuzzy concepts, as developmental pathways that may overlap to some degree, leading to developmental mosaics (intermediates). For example, the whorled leaves of Utricularia purpurea resemble whole shoots, corroborating Arber's partial-shoot theory.

A New Species and Nomenclatural Changes in Neotropical Platymiscium (Leguminosae: Papilionoideae: Dalbergieae)

Summary. One new species, Platymiscium jejunum from Mexico, is described, nine new infraspecific combinations are proposed; and new synonyms are added to P floribundum var. floribundum, P floribundum var. latifolium, and R pinnatum subsp. pinnatum var. pinnatum. The Neotropical genus Platymiscium comprises 18 species (28 taxa) of trees (Klitgaard, in prep.). Four species are morphologically variable and geographically widespread, and 14 species are more restricted, some being very narrow endemics. The genus is uniquely defined within the Leguminosae by the following combination of features: (a) opposite leaves, (b) interpetiolar stipules, (c) yellow papilionoid flowers borne in axillary racemes, and (d) one-seeded samaroid fruits. Platymiscium species occur from about 30'N in Mexico, throughout much of Central and South America to 20'S in eastern Brazil. Species have successfully colonised dry (nine species) as well as humid (nine species) habitats. The systematic study (Klitgaard 1995 unpubl. PhD thesis), from which the present paper is extracted, and a future monograph of the genus (Klitgaard, in prep.) are based on the study of more than 1100 herbarium collections from the following herbaria: AAU, B, BAF, BH, BHCB, BHMH, BM, C, CEPEC, CVRD, EAC, F, FHO, G, GH, HBG, HRB, HUEFS, IAN, IBGE, INPA, IPA, K, L, LD, NY, M, MAD, MBM, MEXU, MG, MO, OXF, P, QAME, QCA, QCNE, R, RB, RC, S, SI, SP, SPF, U, UB, UC, UEC, UPS, US. All the material cited has been seen by the author, unless otherwise indicated.

Taxonomic Notes on the Tribe Psychotrieae (Rubiaceae) in Panama, Western Colombia, and Ecuador

Taxonomic Notes on the Tribe Psychotrieae (Rubiaceae) in Panama, Western Colombia, and Ecuador

Revision of Cosmibuena (Rubiaceae)

Cosmibuena is distinguished by its epiphytic habit, interpetiolar stipules that are also partially fused intrapetiolarly, and salverform white corollas. Four species are recognized: C. grandiflora (Ruiz Lopez & Pavon) Rusby, C. macrocarpa (Bentham) Walpers, C. matudae (Standley) L. O. Williams, and C. valerii (Standley) C. M. Taylor, comb. nov. (= Hillia valerii Standley)

Seedling and shoot morphology of the New Zealand species ofNothofagus(Fagaceae)

Abstract The morphology of the seedlings, young plants, and shoots of adult trees are described for Nothofagus menziesii, N. solandri, N. fusca, and N. truncata. The seedlings are of the Macaranga type. The leaves of the first plumular node are opposite with interpetiolar stipules. The primary axis is orthotropic with spiral phyllotaxis whereas the lateral branches are predominantly plagiotropic with distichous leaves. Terminal buds of the primary axis and of the lateral branches normally abort, growth being continued by pseudo-terminal buds. All four species conform to Troll's Model of tree architecture. Several morphological characters separate the seedling of N. menziesii from the other three species. The significance of shoot morphology to the taxonomy of the genus cannot be assessed until similar studies are made in other regions.

DIVERSE NODAL ANATOMY OF THE CUNONIACEAE

A comprehensive study of nodal anatomy of the Cunoniaceae has revealed an unusually diverse assemblage of nodal types, including patterns with “split‐lateral” traces previously undescribed for dicotyledons. On the basis of leaf arrangement and nodal vascularization, six distinct nodal conditions are recognized in the family. The trilacunar, three‐trace pattern is the ancestral type from which the multilacunar condition evolved by amplification in the number of lateral traces. The “split‐lateral” condition, distinguished by the fusion of lateral leaf traces of adjacent leaves, or the bifurcation of a single trace, and their association with a “common gap,” probably evolved concomitant with the transition from opposite to whorled leaves. The characteristic interpetiolar stipules of the Cunoniaceae are vascularized by veins originating from lateral leaf traces, or by a combination of complete lateral traces and veins arising from lateral leaf traces. Both Aphanopetalum and Bauera possess unilacunar one‐trace nodes. The most satisfactory family placement of both genera remains uncertain, although the unilacunar nodes of Bauera can reasonably be interpreted as a case of reduction from the trilacunar pattern in response to reduced plant size.

Trigonobalanus and its importance in the taxonomy of the Fagaceae

(The contents of this contribution are treated more fully in Kew Bulletin 17, 381-396 (1964) and in a further paper to be published in that journal. A summary only, therefore, is presented in this present account.) A new genus of Fagaceae, Trigonobalanus Forman, was discovered on Mt Kinabalu by the 1961 Royal Society Expedition to North Borneo. Tr. verticillata Forman, now also known to occur in Malaya and Celebes, is most remarkable in having leaves in whorls of three with connate inter-petiolar stipules—characters hitherto unknown in the family. A second species from northern Thailand, Tr. doichangensis (A. Camus) Forman ( = Quercus doichangensis A. Camus), has been added to the genus.