Enigmatic morphology of Djinga felicis (Podostemaceae – Podostemoideae), a badly known endemic from northwestern Cameroon

Djinga is a monotypic genus restricted to the Cameroon Ridge (‘Dorsale Camerounaise’) of NW Cameroon. Besides the type locality Mount Djinga (Adamawa Province, near Tignère), it also grows in waterfalls near Mount Oku (NW Province). This paper describes the structure and development of Djinga felicis using scanning electron microscopy and microtome sections. Cusset's protologue is enriched considerably. Roots are green, dorsiventrally flattened and adherent to submerged rocks. They are broad ribbons or crusts (up to 1 cm broad) which branch exogenously. Root‐borne shoots (up to 17 cm) have filamentous leaves with sheaths and (occasionally) attached stipules. Flowers are borne as part of reproductive short shoots which arise exogenously along the stems and endogenously along the roots. Djinga shows non‐axillary stem branching. Reproductive shoots along the main stem usually stay short. They arise from the abaxial side of double‐sheathed leaves, a key innovation of Podostemoideae. These short shoots shift into pocket‐like stem positions clearly below their associated leaves. Each flower bud inside a spathella is erect, but with an inclined ovary. The flowers are unistaminate with a broad connective. Unlike many other Podostemoideae, the tricolpate pollen grains are arranged in both dyads and monads. The ovary is globular and unilocular. The mature 8‐ribbed capsule dehisces by two slightly unequal valves, releasing 40–50 seeds. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 64–81.     

Diamantina lombardii – an odd Brazilian member of the Podostemaceae

This paper complements the diagnosis of the recently described genus Diamantina and its only species Diamantina lombardii Novelo, Philbrick and Irgang from Minas Gerais (Brazil). Four new features not known from other Podostemaceae–Podostemoideae are documented by microtome sections and SEM graphs: (i) The digitate foliage leaves lack vascular tissue completely. (ii) Leafy shoots produce one or two flowers in terminal and subterminal position. The spathella subtending the subterminal flower is scale-like and positionally homologous to a digitate bract (leaf), whereas the spathella covering the terminal flower bud is tubular (as usual for Podostemoideae). (iii) The usually rudimentary androecium consists of two stamens which form a complete whorl together with three inconspicuous tepals around the gynophore. (iv) The bilocular ovary has an apical cleft. Each carpel tip (hollow inside) is topped by a prominent horn-like stigma. Additional peculiar features of D. lombardii (already mentioned in Philbrick et al., 2004. Syst. Bot. 29, 109–117) are shown: presence of a prominent gynophore (mainly known from African Podostemoideae), and digitate leaves (as found in Cladopus from Eastern Asia to NE Australia).     

Developmental morphology of Ledermanniella bowlingii (Podostemaceae) from Ghana

 Ledermanniella (c. 44 species) is the largest podostemoid genus in Africa. This paper deals with the structure and development of the Ghanaian species Ledermanniella bowlingii (J.B. Hall) C. Cusset (subgenus Ledermanniella). Characters typical for L. bowlingii include: green ribbon-like roots with exogenous lateral roots and endogenous shoots up to 120 cm; most leaves 3–7 times forked, with intrapetiolar stipules; flowers solitary or in clusters, borne on elongate stems or directly on roots; each flower bud inverted within a spathella; flowers unistaminate; tricolpate pollen in dyads; ovary mainly unilocular but bilocular at the base due to a rudimentary septum; mature capsule with eight ribs, 1.0–1.8 mm long, containing 12–34 seeds, dehiscing by two equal valves; capsule stalk with pedicel (10 mm) and gynophore (2 mm); silica bodies absent in all plant parts. Several characters of L. bowlingii are described here for the first time. The paper shows that accurate morphological analyses of African Podostemaceae are badly needed. Received September 30, 2002; accepted November 20, 2002 Published online: March 24, 2003     

Phylogeny and systematics of the tribe Sonerileae (Melastomataceae) in Africa: A revised taxonomic classification

The tribe Sonerileae in tropical Africa and Madagascar is a morphologically diverse lineage that consists of 239 species in 10 genera. In this study, we present the first in-depth phylogenetic analysis of African Sonerileae to test monophyly of the currently recognized genera. Phylogenetic analyses were performed using sequence data from two nuclear (nrITS and nrETS) and three plastid loci (accD-psaI, ndhF and psbK-psbL). Sampling consisted of 140 accessions including 64 African, 27 Malagasy, 46 Asian, and three neotropical Sonerileae together with a broad outgroup sampling (105 spp.). Phylogenetic relationships were inferred using maximum likelihood and Bayesian inference approaches, and a careful reassessment of morphological characters was carried out. Our results neither support the monophyly of the Old World nor African Sonerileae. The monospecific African genus Benna is partially supported as sister to Phainantha, one of the basal neotropical lineages, while African and Malagasy Medinilla are nested among the SE Asian genera. Gravesia (116 spp.), the most species-rich and morphologically diverse genus in Madagascar, is recovered as monophyletic. The African genera of Sonerileae Calvoa, Dicellandra, and Preussiella form well-supported clades. In contrast, Amphiblemma (including Amphiblemma molle) and Cincinnobotrys s.l. (including Cincinnobotrys felicis) are not monophyletic. To accommodate the caulescent C. felicis we propose reinstatement of the monospecific genus Bourdaria. For the distinctive A. molle a new genus Mendelia is described. Calvoa hirsuta is designated here as the type of genus Calvoa, lectotypes are designated for Medinilla engleri and Veprecella lutea, and a neotype is designated for Preussiella kamerunensis.     

Shoot apex and spathella: two problematical structures of Podostemaceae–Podostemoideae

The presence of a shoot apex and shoot apical meristem (SAM), said to be absent in subfamily Podostemoideae (Podostemaceae), is confirmed for Marathrum utile and M. foeniculaceum. The vegetative shoot axis is terminated by a small group of meristematic cells which are surrounded by the tissue of the adnate bases of foliage leaves. The slightly bulged tip of the shoot apex is embraced by the youngest leaf, facing the apex with its adaxial side. The study also refers to the spathella, a cup-shaped structure covering obligatorily the young flower bud in Podostemoideae. The occurrence of two separate peaks in the young spathella of M. foeniculaceum supports the view that the spathella is formed by two fused bracts (hypsophylls). The two bracts are perpendicular to the distichous foliage leaves below the spathella. The scaly leaflet on the spathella of A. latifolia apparently does not represent a rudimentary blade of the spathella, but is interpreted as a separate bract. The occasional occurrence of scales below or above the spathella points to a reduction of bracts that were originally present in greater number on the pedicels.     

Speciation and dietary specialization in Drupa,a genus of predatory marine snails (Gastropoda: Muricidae)

Claremont, M., Reid, D.G. & Williams, S.T. (2012) Speciation and dietary specialization in Drupa, a genus of predatory marine snails (Gastropoda: Muricidae). —Zoologica Scripta, 41, 137–149. We test the competing predictions of allopatric speciation and of ecological speciation by dietary specialization in Drupa, an Indo‐Pacific genus of carnivorous marine gastropods in the family Muricidae. We use a well‐resolved molecular phylogeny (reconstructed from one nuclear and two mitochondrial genes) to show the validity of the traditional species D. elegans, D. rubusidaeus, D. clathrata, D. morum and D. speciosa.‘Drupa ricinus’ is shown to consist of three species: D. ricinus s. s., D. albolabris and a new species, possibly endemic to Japan. ‘Purpura’aperta is transferred to Drupa. Despite potential widespread dispersal and a high degree of range overlap among sister species, range sizes between sister species are highly asymmetric, suggesting that speciation has been predominately peripatric. The exception is the sister pair D. ricinus s. s. and D. albolabris, which have symmetric range sizes and are sympatric over broad Indo‐Pacific ranges. Such symmetry and extensive sympatry are contrary to the predictions of the (peripatric) allopatric model of speciation. Nevertheless, contrary to the predictions of an ecological speciation model based upon dietary specialization, broad dietary range appears to be identical between the species. Small differences in microhabitat preferences (or hypothetical dietary specialization at a fine taxonomic scale) may have been significant in the speciation process or, if initial divergence was allopatric, in permitting subsequent sympatry. Broad dietary shifts appear to have accompanied more ancient divergences within the genus Drupa.     

Light and ethylene effects on assimilate distribution,acid invertase activity and keeping quality of begonia

Flowering plants of Begonia × cheimantha cv Emma and Begonia x hiemalis cv Schwabenland Red were exposed to different light levels (0, 40, 80 M m^–2S^–1) and to ethylene (150 nl 1^–1) in growth cabinets. Increasing irradiance level increased the number of flower buds in both begonia species. The amount of ¹⁴C-assimilates translocated to flower buds and the acid invertase activity in flower buds and flowers also increased with increasing irradiance level. Conversely, treatment with ethylene decreased the accumulation of ¹⁴C in flowers and flower buds, but did not affect acid invertase activity. Ethylene accelerated abscission of flowers and flower buds and increased the number of cup shaped and small flowers.     

EVOLUTIONARY MODIFICATION IN CLARKIA. II. ROLE OF FLOWER BUD PUBESCENCE IN SECTION PHAEOSTOMA

Observations of the habitats and relative flowering of a Clarkia species with hairy flower buds and several with hairless flower buds led to the hypothesis that long hairs on flower buds regulate bud temperature. This hypothesis predicts that hairless buds would be warmer and develop faster than hairy buds, which would be cooler, develop more slowly, and avoid high temperature stress. The hypothesis was tested by comparing flower bud growth rates and temperatures in three genetically similar biotypes of Clarkia unguiculata and in all six species of section Phaeostoma. Flower buds of the three biotypes included hairy (HY) and hairless (HN) from the same coastal population and densely hairy (HD) from an interior locality. The six species included C. unguiculata with densely hairy buds (HD) and five related species with hairless buds. Contrary to expectations, HY buds grew more rapidly than HN buds. HD buds grew more rapidly than either and also more rapidly than the hairless buds of five related species. Again contrary to expectations, the three biotypes of C. unguiculata had equivalent temperature relations, with bud temperatures mostly somewhat below air temperatures. In a comparative experiment, bud temperatures in C. unguiculata approximated air temperatures while bud temperatures in five related species mostly fell well below air temperatures. Thus, predictions of the hypothesis were not borne out. Long bud hairs apparently have minimal effect on bud growth rates and temperatures, and we conclude that physiological adaptations are more important. Bud cooling mechanisms are discussed.     

Reproductive biology and pollination of the carnivorous Genlisea violacea (Lentibulariaceae)

• Genlisea violacea is a Brazilian endemic carnivorous plant species distributed in the cerrado biome, mainly in humid environments, on sandy and oligotrophic soil or wet rocks. Studies on reproductive biology or pollination in the Lentibulariaceae are notably scarce; regarding the genus Genlisea, the current study is the first to show systematic and standardised research on reproductive biology from field studies to describe the foraging of visiting insects and determine the effective pollinators of Genlisea.
• We studied two populations of G. violacea through the observation of flower visitors for 4 months of the rainy and dry seasons. Stigmatic receptivity, pollen viability, and breeding system were evaluated together with histochemistry and morphological analyses of flowers.
• The flowers showed stigmatic receptivity of 100% in open buds and mature flowers, reducing to 80% for senescent flowers. Nearly 80% of pollen grains are viable, decreasing to 40–45% after 48 h. Nectar is produced by glandular trichomes inside the spur. Two bee species are effective pollinators: one of the genus Lasioglossum (subgenus Dialictus: Halictidae) and the other of the genus Ceratina (subgenus Ceratinula: family Apidae). Moreover, bee‐like flies of the Syrphidae family may also be additional pollinators.
• Genlisea violacea is an allogamous and self‐compatible species. The differences in flower‐visiting fauna for both populations can be attributed to factors such as climate, anthropogenic effect, seasonal factors related to insects and plants, as well as the morphological variation of flowers in both populations.

     

Effectiveness of short‐tongued bees as pollinators of apparently ornithophilous New Zealand mistletoes

Abstract The flowers of two species of threatened New Zealand mistletoes (Peraxilla tetrapetala and Peraxilla colensoi, Loranthaceae) have explosive buds that do not open unless force is applied by birds or two species of native short‐tongued bees. Opened flowers are visited by a variety of birds and insects. Although both species of Peraxilla conform to a pollination syndrome of ornithophily, bees may be effective alternative pollinators. We investigated the effectiveness of bees and birds as pollinators of P. colensoi at one site and P. tetrapetala at two sites in the South Island. Bees and other insects outnumbered birds as flower visitors at all three sites. By excluding birds with wire cages, we showed that two bee species regularly open flowers of P. tetrapetala, but only rarely open flowers of P. colensoi. Few pollen grains were deposited when either birds or bees opened buds, so opening buds was not by itself sufficient for adequate pollination. Instead, pollen continued to accumulate over the next 6 or 7 days, even inside cages that excluded birds. Both populations of P. tetrapetala were regularly pollen‐limited, but in different ways. At Ohau, opened flowers gained enough pollen to produce seeds, but many buds were not opened and hence failed to set seed. In contrast, at Craigieburn, nearly all buds were opened, but many of these did not receive enough pollen. These results demonstrate that native bees can partially replace birds as pollinators of mistletoes, despite their apparent ornithophilous syndrome. Ongoing reductions in New Zealand forest bird numbers means that the service bees provide may be important for the long‐term future of these plants.     

New information on host plants and distribution ranges of an invasive gall midge, <Emphasis Type="Italic">Contarinia maculipennis</Emphasis> (Diptera: Cecidomyiidae), and its congeners in Japan

Gall midges of the genus Contarinia (Diptera: Cecidomyiidae) that infest the flower buds of various plant species have been newly found in Japan in recent years. Those infesting the flower buds of Pseuderanthemum laxiflorum (A. Gray) Hubbard ex Baillon (Amaranthaceae) and Jasminum sambac (Linnaeus) Aiton (Oleaceae) in Okinawa Prefecture, and Dendrobium spp. (Orchidaceae) in Mie Prefecture were identified, on the basis of morphological features and molecular information, as an invasive gall midge, C. maculipennis Felt. C. maculipennis was recorded in Mie Prefecture for the first time, and P. laxiflorum is newly regarded as one of the host plants of C. maculipennis. Three other Contarinia gall midges that we found infesting the flower buds of Lycopersicon esculentum Miller, Capsicum annuum Linnaeus (Solanaceae), and Oxalis corniculata Linnaeus (Oxalidaceae) were not identical with C. maculipennis. Among these, the first two, which infested solanaceous plants, were identical. However, the species other than C. maculipennis could not be identified to the species level because morphological differences were obscure and DNA sequencing data of allied congeners have not yet been registered on GenBank.     

Lobatiriccardia yunnanensis,sp. nov. (Metzgeriales,Aneuraceae) from Yunnan,China

Abstract

The genus Lobatiriccardia Furuki is reported as new to China, from the Dulong River valley, Gaoligong Shan range, Yunnan Province and this material is described as a new species endemic to China, Lobatiriccardia yunnanensis Furuki & D.G. Long, the fifth known species in the genus. The differences between the new species and the other members of the genus are enumerated, along with a key to all known species of Lobatiriccardia.     

Molecular analysis of interspecific and intergeneric relationships of Banksia using RAPDs and non-coding chloroplast DNA sequences

 Random amplified polymorphic DNA (RAPD) and chloroplast DNA (cpDNA) markers were used to study interspecific and intergeneric relationships of Banksia (Proteaceae) to aid breeding of the genus for cut flower production. The accepted morphological phylogeny of Banksia, with two subgenera, two sections and 13 series, is unclear regarding the relationships of the commercial cut flower species B. coccinea. Fifteen RAPD primers and a non-coding cpDNA sequence between the trnL (UAA) and trnF (GAA) gene were applied to species of Banksia, the related genus Dryandra, and to Musgravea heterophylla as the outgroup, with cluster analysis applied to the results. The two methods were in broad agreement with each other, and with the accepted taxonomy, with closely related species pairs and groups clustering together, but RAPDs were not informative between distantly related species or species pairs. Banksia coccinea clustered with Dryandra and formed a polytomy with 2 Dryandra species and the two sections of subgenus Banksia. Subgenus Isostylis formed a polytomy with D. formosa, basal to subgenus Banksia, but with B. cuneata and B. illicifolia (both in subgenus Isostylis) polyphyletic. Dryandra did not separate as a clade and fell within Banksia, raising questions about the currently accepted view of the two as sister genera with parallel morphological development. The results indicate that interspecific and intergeneric hybridisation with genus Dryandra and subgenus Banksia may be possible routes for improvement of the commercial species B. coccinea. Received: 25 September 1996 / Accepted: 8 November 1996     

The biogeography of Gunnera L.: vicariance and dispersal

Aim The genus Gunnera is distributed in South America, Africa and the Australasian region, a few species reaching Hawaii and southern Mexico in the North. A cladogram was used to (1) discuss the biogeography of Gunnera and (2) subsequently compare this biogeographical pattern with the geological history of continents and the patterns reported for other Southern Hemisphere organisms. Location Africa, northern South America, southern South America, Tasmania, New Zealand, New Guinea/Malaya, Hawaii, North America, Antarctica. Methods A phylogenetic analysis of twenty‐six species of Gunnera combining morphological characters and new as well as published sequences of the ITS region, rbcL and the rps16 intron, was used to interpret the biogeographical patterns in Gunnera. Vicariance was applied in the first place and dispersal was only assumed as a second best explanation. Results The Uruguayan/Brazilian Gunnera herteri Osten (subgenus Ostenigunnera Mattfeld) is sister to the rest of the genus, followed sequentially upwards by the African G. perpensa L. (subgenus Gunnera), in turn sister to all other, American and Australasian, species. These are divided into two clades, one containing American/Hawaiian species, the other containing all Australasian species. Within the Australasian clade, G. macrophylla Blume (subgenus Pseudogunnera Schindler), occurring in New Guinea and Malaya, is sister to a clade including the species from New Zealand and Tasmania (subgenus Milligania Schindler). The southern South American subgenus Misandra Schindler is sister to a clade containing the remaining American, as well as the Hawaiian species (subgenus Panke Schindler). Within subgenus Panke, G. mexicana Brandegee, the only North American species in the genus, is sister to a clade wherein the Hawaiian species are basal to all south and central American taxa. Main conclusions According to the cladogram, South America appears in two places, suggesting an historical explanation for northern South America to be separate from southern South America. Following a well‐known biogeographical pattern of vicariance, Africa is the sister area to the combined southern South America/Australasian clade. Within the Australasian clade, New Zealand is more closely related to New Guinea/Malaya than to southern South America, a pattern found in other plant cladograms, contradictory to some of the patterns supported by animal clades and by the geological hypothesis, respectively. The position of the Tasmanian G. cordifolia, nested within the New Zealand clade indicates dispersal of this species to Tasmania. The position of G. mexicana, the only North American species, as sister to the remaining species of subgenus Panke together with the subsequent sister relation between Hawaii and southern South America, may reflect a North American origin of Panke and a recolonization of South America from the north. This is in agreement with the early North American fossil record of Gunnera and the apparent young age of the South American clade.     

Description of Eucalyptodiplosis chionochloae sp. nov., a cecidomyiid feeding on inflorescences of Chionochloa (Poaceae) in New Zealand

Abstract

A cecidomyiid that feeds on developing seeds in the inflorescences of the New Zealand tussock grasses Chionochloa australis, C. conspicua, C. crassiuscula, C.flavescens, C. macra, C. oreophila, C. pallens, C. rigida, C. rubra, C. spiralis and C. teretifolia is formally described from C. pallens. The new species, named Eucalyptodiplosis chionochloae Kolesik, is the most ubiquitous of flower feeders of Chionochloa. Its larvae do not form galls but feed on the developing seeds in autumn, overwinter as diapausing larvae inside the floret, and pupate then rapidly eclose in summer, sometimes after extended diapause. Methods for rearing adults are described. Based on its morphological characters this species is most closely related to two described congeners that form galls on buds of Eucalyptus trees in Australia. Seed predation by Eucalyptodiplosis chionochloae larvae appears to be the primary driver of the extreme mast seeding (variation among years in flower crops) seen in the host Chionochloa species.     

Phylogenetics of Darwiniothamnus (Asteraceae: Astereae) – molecular evidence for multiple origins in the endemic flora of the Galápagos Islands

Aim The aims of this study were (1) to investigate whether the two growth forms of Darwiniothamnus Harling (Asteraceae) originated from the colonization of a single ancestor, (2) to identify the closest relative(s) of Darwiniothamnus, and (3) to review molecular phylogenies from other plant groups to infer the origin of Galápagos endemics. Location Darwiniothamnus is endemic to the Galápagos Islands. Methods All putative relatives of Darwiniothamnus plus 38 additional species were included. Nucleotide sequences of the internal transcribed spacers of the nuclear ribosomal DNA were used for Bayesian and parsimony analyses. Results Darwiniothamnus is polyphyletic. Two species (D. lancifolius (Hook. f.) Harling and D. tenuifolius (Hook. f.) Harling) are woody shrubs that usually grow to 1–2 m in height; they belong to a clade composed of species otherwise restricted to the Caribbean. These two species are sister to Erigeron bellidiastroides Griseb., a herbaceous species endemic to Cuba. The third species (D. alternifolius Lawesson & Adsersen) is a perennial herbaceous plant, woody at the base and reaching only up to 50 cm in height. It is sister to two Chilean (Coquimbo–Valparaiso region) species that also have a perennial herbaceous habit: E. fasciculatus Colla and E. luxurians (Skottsb.) Solbrig. They are placed in an assemblage restricted to South America. The review of previous molecular phylogenetic studies revealed that two of the endemic genera and endemic species of three non‐endemic genera have their closest relatives in South America. Endemic species belonging to three non‐endemic genera have sister species in North America or the West Indies. One endemic genus and endemic species in three non‐endemic genera have sister taxa with a widespread continental distribution, or their molecular phylogenies yielded equivocal results. Main conclusions The flora of Galápagos has affinities with both North America (including the Antilles) and South America. Darwiniothamnus exhibits both patterns: two species of this genus are sister to a taxon endemic to Cuba, supporting a connection between the Cocos plate and the West Indies; the third species, D. alternifolius, provides a link with the Coquimbo–Valparaiso region, suggesting a biogeographical connection between the Nazca plate and southern South America.     

广西报春苣苔属一新种及其系统位置(英文)

报春苣苔是一类生长在石灰岩基质上的多年生草本植物,目前已知的种类160余种,主要分布在我国南部和越南北部的石灰岩地区。该属植物许多种类分布极其狭域,往往仅零星分布在某个或少数几个地点。近年来,该属植物许多新种类不断地被发现和报道,预示着该属植物可能有更加丰富的多样性。该研究报道了在广西博白县发现的该属植物一新种。从形态上判断,该新种属于广义报春苣苔属,其具有的一些特别的形态特征,如花冠下唇比上唇长得多,上唇内部具有两个近圆形斑点(其它多数种类具有条形斑点),而易于与本属其它物种区分。而且,基于叶绿体mat K基因序列重建的系统发育关系表明,该新种的确属于报春苣苔属且广义报春苣苔属是单系类群。该新种与钟冠报春(P.swinglei)和疏花报春(P.laxiflora)最为近缘,其mat K基因与后两者分别有5个和11个碱基差异,暗示这些物种间经历了较长时间的独立演化或mat K基因在这些物种中具有较高的碱基替换速率。另外,该新种只生长在丹霞岩石上,而其近缘种以及同属大多数其它种类都生长在石灰岩基质上,暗示该新种获得了特殊的适应能力以及与其它近缘种间存在生态隔离。该新种以及近年来本属许多其它新种类的发现,进一步增加了对该属植物多样性的认识,以及该属植物的演化与多样性分化之谜。这些物种所具有的高度区域或局域特有性和稀有性,以及形态上的特殊性和遗传上的独立性,进一步强化了对该属植物开展保护的重要性。     

八角属植物分类

根据对18个国家和地区121个标本馆收藏的万余份八角属植物标本研究,结合在国内8个省区野外调查、采集、引种和对生长发育与物侯的观察,本文对世界性八角属植物做了分类学修订。根据花蕾和花被片形态特征的变异,将八角属分为2组:八角组-含9种1亚种,其花蕾卵球形,花被片长圆形、椭圆形、披针形至狭舌状,扁平;八角茴香组-含25种2亚种1变种,其花蕾球形,花被片宽卵形至圆形,下凹。将凹脉组作为八角组的新异名,圆被亚属作为八角茴香组的新异名;指定了红茴香和柬埔寨八角的后选模式。本文还分析了八角属植物的分类学性状,作出有分类检索表,提供有各种植物的地理分布资料,列举出查阅的主要标本,并对各分类单元均作了分类学注释。