Tubular Corolla Research Articles

Ligularialushuiensis (Asteraceae, Senecioneae), a new species from northwestern Yunnan, China.

Ligularialushuiensis, a new species from northwestern Yunnan, China, is described and illustrated. It was tentatively placed in L.sect.Ligulariaser.Ligularia on the basis of the pinnate-palmate leaf venation, racemose synflorescence and pappus which is as long as tubular corolla. Within the series, it appeared somewhat close to both L.lamarum and L.pseudolamarum. However, L.lushuiensis can be easily distinguished from the latter two species by, among other characters, the leaf margin, bract size, involucre shape and size, and number and width of ray florets. Morphologically, L.lushuiensis is also superficially similar to L.secunda but differs readily by having distally shortly yellowish and brownish puberulent stems, palmately-pinnately veined leaves regularly dentate at margin, scarious, brown and larger bracts, and larger ray laminae. In addition, a distribution map and a diagnostic key to Chinese species of L.ser.Ligularia are also provided.

Botanical Description, Cultivation Practices, Essential Oil Composition and Therapeutic Values of Origanum vulgare L. and its Future Prospective

The Lamiaceae family is of great diversity and variety, with a cosmopolitan distribution. Plants in this family are characterized by verticillaster inflorescence, two-lipped open-mouthed tubular corolla, opposite decussate leaves, quadrangular stem, etc. Most of the species belonging to the family are aromatic and possess essential oils. Origanum vulgare L., also known as Vantulsi or Badri tulsi, is an important herb that is commonly used for it’s aromatic properties. Oregano's leaves and flowering parts contain essential oil glands that produce volatile oil, which is what gives the plant its fragrance. Carvacrol and/or thymol make up the majority of the essential oil of Oregano, with γ-terpenine, p-cymene, linalool, terpenine 4-ol, and sabinene hydrate. These constituents are primarily responsible for the oil's antiviral, antiseptic, antimicrobial, antioxidant, antifungal, anticoagulant, and energetic action properties. In this review article, we shed light on the origin, distribution, botanical description, cytological and breeding studies, essential oil and its constituents, biological activities, cultivation practices and therapeutic values of Origanum vulgare L.

FIRST REPORT OF NECTAR ROBBING BY SWORD-BILLED HUMMINGBIRDS ENSIFERA ENSIFERA

A growing number of hummingbird species are known to practice nectar robbing. Hummingbirds that rob nectar tend to have short bills and to rob flowers with long, tubular corollas that prevent the birds from accessing nectar through its openings. We document that Sword-billed Hummingbirds Ensifera ensifera, which have the longest bills of any hummingbird species, are secondary nectar robbers on flowers of the red angel’s trumpet Brugmansia sanguinea, which have long tubular corollas and are regularly pollinated by Sword-billed Hummingbirds. When obtaining nectar through the floral opening of B. sanguinea, Sword-billed Hummingbirds' heads may be completely enveloped by the flower, severely limiting their vision. Sword-billed Hummingbirds might be at a lower risk of predation when they rob nectar than when they insert their heads into the floral opening. Thus, nectar robbing in this species might function to reduce predation risk, although we have no data to support this speculation.

Bloodstained flowers and bloodthirsty flies.

This article is a Commentary on Heiduk et al. (2023), 239:1490–1504.

Sympetaly in the mimosoid clade (Leguminosae, Caesalpinioideae): An unusual trait in the rosid group

Sympetaly is a notable feature within the mimosoid clade (Leguminosae: Caesalpinioideae), specially as it is uncommon in rosids. The way the petals are organized, forming a tubular corolla by the union of the petals directly affects the perception of pollinators. This study examines whether the petal union leading to a sympetalous corolla in the mimosoid clade is widespread and whether there is variation in type and extent. For this purpose, floral buds and flowers of 16 species from 13 genera were collected, fixed, and processed for analysis by light and scanning electron microscopy. Most species studied display a pentamerous sympetalous corolla with free lobes. The petal primordia are individualized and emerge simultaneously on the floral apex, alternating with the sepal primordia. Petals remain free at the beginning of the intermediate stages of development, and subsequently, the petals curve and approach each other, and their margins touch. Epidermal papillae are found on the petals’ apical margin interconnecting the lobes, which enclose the inner organs of the floral bud. The structure of the sympetalous corolla is variable regarding the type and extent of the union. Four different types of sympetaly were found and classified as follows: 1. full connation - petals fully united along their length; 2. connation-coherence - petals genuinely united in the basal portion and coherent in the median and apical portion; 3. full coherence - petals intertwined with papillae throughout; and 4. partial coherence - free petals at the base and intertwined with papillae in the middle and apical portion. Thus, sympetaly of mimosoid legumes results from postgenital union of the petals at the apical, median, and basal regions during their development by tissue union (connation), intertwining of epidermal papillae (coherence), or both processes. The mucilage cells found along the petals guarantee the stabilization and flexibility of the tubes, in addition to contributing to the protection of the internal organs of the flower. Although more studies on floral development are needed to understand the evolution of this unusual trait, connation appears to be a derived trait within mimosoids.

Two new species of Eperua (Leguminosae, Detarioideae, Detarieae) from the Amazon and Cerrado Biomes discovered in a botanical garden and a backyard

In this study, we describe two new species of Eperua, E. cerradoensis and E. manausensis. Eperua cerradoensis is the first species of the genus described from the Cerrado Biome (Brazil); all other 16 species, including the other new species described here E. manausensis, are endemic to the Amazon region (Amazon basin and the Guiana Shield). Both species have short and erect inflorescences. Eperua cerradoensis has a non-tubular corolla, white petals, and exserted stamens, and is most similar to E. duckeana and E. schomburgkiana, from which it differs by the bracteole size and phenology, flower indumentum, besides other vegetative characteristics. Eperua manausensis has a tubular corolla, pink to purple petals, and inserted stamens, and it is most similar to E. grandiflora subsp. guyanensis, but differs from it by the bracteole position and phenology and flower indumentum. The type localities of both species are very unusual: a backyard (E. cerradoensis) and a botanical garden (E. manausensis). The two species have been collected in the last five years. These discoveries show that new undescribed species can be found even in more disturbed areas and that comprehensive knowledge of the flora requires new collections and more taxonomists.

Phylotranscriptomics of Swertiinae (Gentianaceae) reveals that key floral traits are not phylogenetically correlated.

Establishing how lineages with similar traits are phylogenetically related remains critical for understanding the origin of biodiversity on Earth. Floral traits in plants are widely used to explore phylogenetic relationships and to delineate taxonomic groups. The subtribe Swertiinae (Gentianaceae) comprises more than 350 species with high floral diversity ranging from rotate to tubular corollas and possessing diverse nectaries. Here we performed phylogenetic analysis of 60 species from all 15 genera of the subtribe Swertiinae sensu Ho and Liu, representing the range of floral diversity, using data from the nuclear and plastid genomes. Extensive topological conflicts were present between the nuclear and plastome trees. Three of the 15 genera represented by multiple species are polyphyletic in both trees. Key floral traits including corolla type, absence or presence of lobe scales, nectary type, nectary position, and stigma type are randomly distributed in the nuclear and plastome trees without phylogenetic correlation. We also revealed the likely ancient hybrid origin of one large clade comprising 10 genera with diverse floral traits. These results highlight the complex evolutionary history of this subtribe. The phylogenies constructed here provide a basic framework for further exploring the ecological and genetic mechanisms underlying both species diversification and floral diversity.

Raphiocarpussinovietnamicus (Gesneriaceae), a new species from southern China and central Vietnam

Raphiocarpus sinovietnamicus, a new species of Gesneriaceae from China and Vietnam, is described and illustrated here. It is morphologically close to R. axillaris and R. tamdaoensis, but can be distinguished from the later two by its broadly tubular corolla tube and red to purple‐red, purplish‐yellow corolla outside. Detailed morphological description together with color illustration, information on phenology, distribution, ecology and preliminarily conservation status of the new taxon was also presented.

Testing candidate genes linked to corolla shape variation of a pollinator shift in Rhytidophyllum (Gesneriaceae).

Floral adaptations to specific pollinators like corolla shape variation often result in reproductive isolation and thus speciation. But despite their ecological importance, the genetic bases of corolla shape transitions are still poorly understood, especially outside model species. Hence, our goal was to identify candidate genes potentially involved in corolla shape variation between two closely related species of the Rhytidophyllum genus (Gesneriaceae family) from the Antilles with contrasting pollination strategies. Rhytidophyllum rupincola has a tubular corolla and is strictly pollinated by hummingbirds, whereas R. auriculatum has more open flowers and is pollinated by hummingbirds, bats, and insects. We surveyed the literature and used a comparative transcriptome sequence analysis of synonymous and non-synonymous nucleotide substitutions to obtain a list of genes that could explain floral variation between R. auriculatum and R. rupincola. We then tested their association with corolla shape variation using QTL mapping in a F2 hybrid population. Out of 28 genes tested, three were found to be good candidates because of a strong association with corolla shape: RADIALIS, GLOBOSA, and JAGGED. Although the role of these genes in Rhytidophyllum corolla shape variation remains to be confirmed, these findings are a first step towards identifying the genes that have been under selection by pollinators and thus involved in reproductive isolation and speciation in this genus.

Macro- and micro-morphological characteristics of Kickxia Dumort. and some related taxa in Saudi Arabia

The morphological and anatomical aspects of 13 species belonging to genera Kickxia, Scrophularia, and Plantago of Saudi Arabia reveal that the species of Kickxia and Scrophularia are distinct from Plantago major. The most notable morphological differences are the absence of adventitious roots and the presence of acaulescent stem in the species of Kickxia and Scrophularia and the existence of adventitious roots and the absence of acaulescent stem in P. major. The species of Plantago possessed rose-shaped radical leaves, whereas the rest of the species studied had cauline leaves or both. The species of Kickxia and Scrophularia have pentamerous flowers with bilabiate corollas, whereas, P. major has tetramerous flowers with tubular corollas. The separation of P. major from the rest of the studied species is the most obvious result obtained from the dendrogram, and this result is consistent with some traditional taxonomic studies that placed Kickxia in the Scrophulariaceae species while separating P. major into an independent family Plantaginaceae. The anatomical findings revealed that the upper and lower epidermal cells of the leaves were irregular with undulate walls in all analyzed species, except in P. major, where they were polygonal with straight walls. Only P. major had amphianisocytic paracytic stomata, but eight Kickxia species had anomocytic stomata and K. hastata and K. abhaica, and the two Scrophularia species had anisocytic stomata. Therefore, this study suggests the retention of the Kickxia in Scrophulariaceae s.l. and maintaining Plantago in Plantaginaceae s.s. Bangladesh J. Plant Taxon. 29(1): 1-11, 2022 (June)

Two new pendulous epiphytic Columnea L. (Gesneriaceae) species from the Chocó forests of the Northern Andes.

Exploratory field expeditions to the Chocó forests in the northwestern slopes of the Ecuadorian and Colombian Andes resulted in the discovery of two new species of Columnea (Gesneriaceae). Columneafluidifolia J.L.Clark & F.Tobar, sp. nov., is described as a narrow endemic from Bosque Protector Mashpi and surrounding areas in the province of Pichincha in northern Ecuador. Columneapendens F.Tobar, J.L.Clark & J.F.Sm., sp. nov., is described from recently discovered populations in the provinces of Carchi and Santo Domingo de los Tsáchilas (Ecuador) and the departments of Cauca and Nariño in southwestern Colombia. The two new species are pendent epiphytes with elongate shoots and shallowly bilabiate to nearly tubular corollas. Descriptions, complete specimen citations, and a distribution map are provided. Based on IUCN guidelines, a preliminary conservation status of Critically Endangered (CR) is provided for C.fluidifolia and Endangered (EN) is provided for C.pendens.

Oreocharisphuongii (Gesneriaceae), a new species from central Vietnam.

Oreocharisphuongii, a new species of Gesneriaceae from central Vietnam, is described and illustrated here. The new species is most similar to O.longifolia by sharing peduncles up to 22 cm long, bracts 2, zygomorphic, yellow flowers with tubular corolla, stamens 4 with two pairs of coherent anthers and capsules up to 6 cm long. It mainly differs from the latter by the combination of some morphological characters of leaves (shape, base, apex and margin), size of calyx lobes, indumentum of corolla tube and inner surface of three lower corolla lobes. Detailed morphological description together with colour illustration, information on phenology, distribution, ecology, preliminarily conservation status of the new species and comparison with its similar species are also presented.

Ligulariamonocephala (Asteraceae, Senecioneae), a remarkable new species from Hubei, China.

Ligulariamonocephala, a remarkable new species from Hubei, China, is described and illustrated. It is readily distinguishable in the whole genus by character combination of the reniform to cordate-reniform leaf blades which are palmately-pinnately veined and abaxially purplish red, the solitary and erect capitula, and the pappus which are as long as or slightly longer than tube of the tubular corolla. A detailed description and distribution map of the species are also presented herein.

Ligularia pseudolamarum (Asteraceae, Senecioneae), a new species from southeastern Xizang, China

Ligularia pseudolamarum, a new species from southeastern Xizang, China, is described and illustrated. It is tentatively nested in L. sect. Ligularia ser. Ligularia based on its pinnate–palmate leaf venation, racemose synflorescence and pappus which is as long as or slightly shorter than the tubular corolla. Within the series, it is apparently closely related to both L. lamarum and L. subspicata, however, L. pseudolamarum is easily distinguished from the latter two species by its stem indumentum, leaf margin, bract texture and color, capitulum number and ray floret number and size. In addition, a distribution map and a diagnostic key to all Chinese species of L. ser. Ligularia are also provided.

DIONYSIA SPLENDENS (PRIMULACEAE), A NEW SPECIES FROM THE FARS PROVINCE OF IRAN

Dionysia splendens Alipour, Mehregan & Lidén, sp. nov., from Fars, Iran, is a unique species that cannot be easily accommodated in any hitherto recognised section of the genus and is immediately recognised by its large flowers and pectinate leaves with very broad pale and thick midvein. It agrees with Dionysia cespitosa Duby (Boiss.) in the small flat leaves, stalked inflorescence with large bracts, and few large ellipsoid seeds, but differs in the tubular calyx and large purplish-blue corolla. It is also somewhat reminiscent of Dionysia viva Lidén & Zetterl. in growth habit and inflorescence structure, but that species has large irregularly dentate leaves, yellow corolla and numerous small angular seeds. Dionysia splendens is so far known from a single locality with c.200 mature individuals. An updated key to Dionysia species in the Zagros mountains is provided.

Taxonomic revisions in Fridericia (Bignonieae, Bignoniaceae) I: the “Acrodromous venation” and “Piriadacus” clades

Fridericia is a conspicuous genus of neotropical lianas, with 60 species distributed among seven lineages that are broadly distributed through the neotropics in both dry and wet environments. As part of ongoing taxonomic studies of the genus, we provide taxonomic revisions of two clades: (1) the “Acrodromous venation” clade and (2) the “Piriadacus” clade. The former is characterized by 1- or 2-foliolate leaves with acrodromous venation, tubular calyces and coriaceous fruits with slightly raised edges. The latter is recognized by the red, pink-reddish or orange, tubular corolla and exserted or sub-exserted anthers. We recognize two species in each lineage and provide identification keys, morphological descriptions, illustrations, distribution maps and comments on the distribution, phenology, conservation status and taxonomy. We propose the lectotypification of 13 names: Arrabidaea brachypoda var. acuminata, A. brachypoda var. attenuata, A. brachypoda var. firma, A. brachypoda var. induta, A. brachypoda var. rigida, A. platyphylla var. lasiorrhachis, A. platyphylla var. puberula, Bignonia brachypoda var. firmula, B. erubescens var. breviflora, B. erubescens var. subtruncata, B. regnelliana, Cuspidaria erubescens var. glabrescens and Petastoma simplicifolium. We further correct the typification of B. erubescens var. breviflora and B. erubescens var. subtruncata and propose two new synonyms for F. platyphylla (i.e. A. celastroides and B. violacea).Citation: Kaehler M. & Lohmann L. G. 2021: Taxonomic revisions in Fridericia (Bignonieae, Bignoniaceae) I: the “Acrodromous venation” and “Piriadacus” clades. – Willdenowia 51: 181–194.Version of record first published online on 21 June 2021 ahead of inclusion in August 2021 issue.

Flowers of Apocynaceae in amber from the early Eocene of India.

Early Eocene ambers of the Cambay lignite in Gujarat, India, are well known for their diverse insect fauna and dispersed pollen, but the included flowers have received limited attention. The fossil record of Apocynaceae is relatively poor, and the distinctive floral characters of this family have not been recognized in the fossil record before. Remains of tiny flowers in amber were studied by micro-CT scanning, reflected light, and epifluorescence microscopy. Flowers of Maryendressantha succinifera gen. et. sp. n. have actinomorphic, pentamerous, tubular corollas 2.2-2.3 mm wide, and 1.7-2.1 mm deep with sinistrorse aestivation and androecia consisting of a whorl of five stamens attached by short filaments to the lower half of the corolla tube. Anthers are ovate, rounded basally and apically tapered with their connectives convergent with one another in a conical configuration. The pollen is globose, psilate, tricolporate, and very small (10-11 µm). The combined characters indicate a position within the grade known as subfamily Rauvolfioideae. These fossils, as the oldest remains of Rauvolfioids, complement the fossil records of Apocynoid and Asclepioid fossil seeds from other regions, demonstrating that the Apocynaceae were well established by the early Eocene, mostly consistent with prior divergence estimates for the phylogeny of this family. Potential pollinators, also preserved in the Cambay amber, include mosquitos, gnats, small moths, and stingless bees.

Reproductive biology of Tabebuia pallida (Lindl.) Miers. (Bignoniaceae) collection of Purwodadi Botanic Garden

Botanic garden play a central role in the ex-situ plants conservation. It is important to maintain the survival life of the living plant collections. Knowledge on the details of reproductive biology of the living collections becomes vital to monitor the success or failure of conservation efforts. Tabebuia pallida (Lindl.) Miers. (Bignoniaceae) is one of the living plants collection in Purwodadi Botanic Garden that need to be monitored. So far information on the reproductive biology of this species is still limited. Based on that, in relation to the conservation effort, the objectives of this study were to provide knowledge about the reproductive biology of T. pallida. The research was conducted at Purwodadi BG, from September 2019 to February 2020. Several important aspects of reproductive biology, including flower biology, pollen viability and stigma receptivity, breeding system (Out-Crossing Index), and pollination biology were investigated. The results showed that T. pallida was monocious, has a pinkish tubular corolla with a yellow throat. There was no spatial separation between the anther and stigma. At the time of anthesis, both pollen and stigma have been receptive. Based on flower biology, pollen ornamentation (reticulate type), and the Out-Crossing Index (OCI=3), the flower showed some characters of entomophily, but self-pollination was possible. There are some insects visitor, but that acts as a pollinating agent was Vespula. The availability of effective pollinators in botanic garden was an obvious requirement for successful plants conservation.

Different ways to obtain similar results: the development of the corolla and epipetaly in Rubieae (Rubioideae, Rubiaceae)

Background and aims – Rubieae is a tribe in the subfamily Rubioideae characterised by herbaceous plants with verticillate leaves and flowers with a rudimentary or absent calyx and a short, cup-shaped corolla. This is in contrast to the flowers of most other Rubiaceae, in which the tubular corolla is longer than the corolla lobes. Also, the description by Payer, a French 19th century pioneer of floral ontogenetic research, of the floral development in Asperula, Galium, and Rubia deviates from recent insights about the development of tubular corollas, which are based on investigations of flowers of tropical Rubiaceae. Tubular corollas are currently considered as resulting from the development of underlying annular intercalary meristems, whereas Payer explained the tubular corollas in the three taxa by postgenital fusion. We therefore tested both hypotheses in six Rubieae genera, including the three taxa studied by Payer.Methods – Floral ontogeny of ten species in six Rubieae genera based on scanning electron (SEM) and light microscopy (LM). Conclusions – Our results suggest that, in all species studied, the mature phenotype of the corolla as well as the epipetaly of the stamens is caused by a combination of three developmental processes (the development of a stamen-corolla tube, the development of a corolla tube sensu stricto, and postgenital fusion), and the relative moment of activation of each of these processes during floral development (plastochron variation or heterochrony).

Comparative floral structure and evolution in Galipeinae (Galipeeae: Rutaceae) and its implications at different systematic levels

AbstractGalipeinae (Rutoideae) is the most species-rich subtribe of Rutaceae in the Neotropics. The taxonomy of Galipeinae is complex as molecular phylogenies demonstrate that rearrangements of genera are necessary to reach the monophyly of the subtribe. A few detailed studies have found variability in floral features, such as different patterns of organ fusion and symmetry, with potential systematic importance. However, this was shown for a limited number of taxa. This study aimed to provide a broader comparative account of the floral structure of Galipeinae and closely related taxa of Rutoideae. Some floral features, such as the cochlear aestivation of petals and a free zone of carpels, support the monophyly of Galipeinae without Adiscanthus. Other features, such as apocarpy, anacrostyly, antitropous ovules and zig-zag micropyles, also provide support for the affinity of Rutaceae in Sapindales. Furthermore, complex patterns of organ synorganization of Galipeinae are more diverse than previously shown, and are probably correlated to other features that are not found elsewhere in Sapindales. Finally, we identified homoplastic features that are also widespread in asterids, probably related to similar floral functions, such as variable patterns of monosymmetric tubular corollas, two fertile adaxial stamens with basal appendages of variable length and herkogamy.