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1.
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Three new species of the genus Stelis from Mexico are described and illustrated; they were recently collected in the Tacana volcano region of Chiapas, and are named as S. annedamoniae, S. hagsateri, and S. soconuscana. For each species information is provided about habitat, phenology, and conservation status, and the relationships with similar taxa are discussed. Stelis andamoniae is similar to S. hagsateri and both are sympatric at the Tacana volcano; they are members of the Stelis argentata complex. The first has red-wine flowers, and glabrous sepals, while S. hagsateri has greenish-yellow flowers and glandular-papillose sepals. Stelis soconuscana is similar to S. bidentata, from which it is different by its broader leaves, raceme as long as the leaf, smaller flowers, and its distribution.  相似文献   

3.
Claes Persson 《Brittonia》2003,55(2):176-201
Agouticarpa, a new genus of the informalAlibertia group (Rubiaceae), is described and illustrated. It comprises six species, and occurs from Costa Rica to Bolivia. Three species are here described as new:Agouticarpa grandistipula, A. hirsuta, andA. velutina. Additionally, three new combinations are made:A. curvifolia andA. williamsii (previously inGenipa) andA. isernii (previously inAlibertia). Agouticarpa is characterized by being dioecious, having elliptic to abovate, membranaceous stipules, male flowers in a branched dichasial or thyrse-like inflorescence, a poorly developed cup-shaped calyx, pollen grains with 3–7 apertures, and large globose fruits.  相似文献   

4.
A new species of Euphorbiaceae, Croton borbensis, is described and illustrated from western Amazonian Brazil. It shares features similar to another white sand Amazonian species, C. dissectistipulatus, but differs in having leaves with a serrulate-glandulose margin, no evident stipules, staminate flowers with six stamens and glabrous pedicels, pistillate flowers with few, shortly stipitate glands on the calyx, and a glabrous ovary. Croton borbensis is tentatively placed in section Barhamia.  相似文献   

5.
This paper contributes to the knowledge of the pingue group of species within the genus Diphascon. Three new species are described, Diphascon (D.) polare, D. (D.) dastychi and D. (D.) victoriae, from Victoria Land (Antarctica); they differ from other species of the pingue group in characters of the bucco-pharyngeal apparatus. D. polare and D. victoriae differ also in the claw shape. A key is provided to the Diphascon pingue group. Accepted: 30 November 1998  相似文献   

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7.
Mentzelia hualapaiensis, a new species of Mentzelia sect. Bartonia, is described from the Grand Canyon region of Arizona. The new species is closely related to M. puberula, which is found west of M. hualapaiensis along the Colorado River, and to M. oreophila, M. polita, and M. tiehmii. It shares with these species a suffrutescent shoot system characterized by a subterranean, branching caudex, multiple annual branches, and similar leaves that have shallowly lobed or toothed to entire laminas. The flowers of M. hualapaiensis differ from those of its closest relatives in having cream-white, linear to narrowly spatulate petals and staminodes, characteristics that are convergent with those of the flowers of the Chihuahuan Desert species M. humilis.  相似文献   

8.
Jin XiaoHua  Li Heng 《Brittonia》2007,59(3):243-244
Listera fugongensis, a new species from Yunnan, China, is described and illustrated. The new species is probably related to Listera nipponica, but differs from it by having green flowers, petals slightly wider than lateral sepals, and a toothed lip with ciliate margins.  相似文献   

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10.
Abstract. Thirteen species of Australian acacias are invasive plants in agricultural and native vegetation areas of South Africa. Biological control programmes for Australian acacias in South Africa have been implemented and are aimed at suppressing reproductive vigour and, in some cases, vegetative growth of these weeds. Gall-forming midges are under consideration as potential biological control agents for invasive acacias in South Africa. Entomological surveys in southern Australia found a diverse cecidomyiid fauna associated with the buds, flowers and fruits of Acacia species. Nine new Dasineura species are described and two species, D. acaciaelongifoliae (Skuse) and D. dielsi Rübsaamen, are redescribed. The newly described taxa are D. fistulosa sp.n. , D. furcata sp.n. , D. glauca sp.n. , D. glomerata sp.n. , D. oldfieldii sp.n. , D. oshanesii sp.n. , D. pilifera sp.n. , D. rubiformis sp.n. and D. sulcata sp.n. All eleven species induce galls on ovaries and prevent the formation of fruit. Two general types of gall are caused. Type A comprises woody, tubular galls with larvae living inside ovaries (D. acaciaelongifoliae, D. dielsi, D. fistulosa, D. furcata, D. glauca, D. glomerata, D. oldfieldii). Type B includes soft-tissued, globose galls that belong to four subtypes: inflated, baglike, hairy galls with larvae living between ovaries (D. pilifera); pyriform, pubescent swellings with larvae living inside ovaries (D. rubiformis); globose, hairy, swellings with larvae living superficially on ovaries in ovoid chambers (D. oshanesii); and inconspicuous, glabrous swellings with larvae living superficially on ovaries in shallow groovelike chambers (D. sulcata). The gall types are associated with a particular pupation pattern. In type A galls, larvae pupate within larval chambers in galls, whereas in type B galls pupation takes place between ovaries in galls or in the soil beneath the host tree. Gall midges responsible for the same general gall type are morphologically related and differ from species causing the other gall type. Phylogenetic analysis of a 410 bp fragment of the mitochondrial cytochrome b gene supports the division of the gall midge species into two groups except for D. sulcata, which appears as a subgroup of the group causing type A galls. The interspecific divergence values in group A species were between 0.5 and 3.9% with intraspecific divergence estimates of 0–0.2%. Gall midges causing type B galls had interspecific divergence values of 4.6–7.3% and intraspecific divergence values of 0–3.7%. Closely related biology and morphology together with low cytochrome b divergence estimates suggest a more recent speciation in group A when compared with species of group B. Dasineura rubiformis and D. dielsi are proposed as potential biological control agents for Acacia mearnsii De Wild. and Acacia cyclops A. Cunn. ex G. Don, respectively, in South Africa due to their narrow host range and ability to form high population densities that reduce seed formation. Both species produce galls with low biomass, which makes them compatible with commercial exploitation of their host species in Africa.  相似文献   

11.
This paper describes Ascogrammitis, a new genus of grammitid ferns formerly combined under Terpsichore. Seventeen species are recognized, including five new ones: A. clavigera, A. colombiensis, A. loxensis, A. oxapampensis, and A. tungurahuae. New combinations are made for A. alan-smithii, A. anfractuosa, A. angustipes, A. athyrioides, A. clathrata, A. cuencana, A. david-smithii, A. dilatata, A. nana, A. pichinchae, A. pichinchensis, A. stuebelii, and a lectotype is chosen for Polypodium induens. A key is provided to distinguish the species, and illustrations are provided for 12 species. The genus occurs primarily in neotropical cloud forests, with the greatest diversity in the Andes. Ascogrammitis is one of two monophyletic groups of grammitid ferns that are consistently associated with Acrospermum, an epibiotic bitunicate ascomycete that produces black clavate fruiting bodies.  相似文献   

12.
A synopsis of the annual genus Poteranthera is presented here. Three species are recognized including the newly described Poteranthera windischii. Poteranthera is characterized by its annual life cycle, generally linear leaves that have conspicuous gland-tipped hairs on the lamina margin, 5-merous flowers with a constriction at the level of the torus, one cycle of stamens reduced to staminodia or absent altogether, three locular ovary, and reniform seeds with a foveolate testa. The flowers of the new species P. windischii are strongly heterandrous, where the usual set of stamens that bees harvest pollen from is reduced to staminodia and the stamen set that deposits pollen on the bee has large yellow ventral appendages that possibly function as pollen mimics and result in deceit pollination. This hypothesis is supported by experiments that have demonstrated innate preferences of female bees for yellow, UV absorbing colors in flowers. Species of Poteranthera are extremely rare, known from very few specimens and possibly highly endangered.  相似文献   

13.
Govenia rubellilabia, a new terrestrial orchid from Sierra Madre de Chiapas, Mexico, is described and illustrated. Diagnostic characters of this new species are compared with other species ofGovenia. Govenia rubellilabia is similar in appearance toG. matudae, but it can be distinguished from this species by a shorter inflorescence with fewer flowers, green-yellowish tepals, a reddish lip lacking spots in the margin of the apex, and by a shorter anther beak.  相似文献   

14.
Miconia walterjuddii, a new species of Melastomataceae from the mountains in northeast Cuba, is described. This species can be easily assigned to Miconia section Chaenopleura due to its short anthers that open by two longitudinal slits. Sequence data from nrITS confirm this placement. This new species is characterized by its inconspicuous lepidote indumentum of minute adpressed scales ca. 0.05 mm long; small flowers in dichasia, forming a compact, many-flowered, rounded to subcorymbose cymes, with purple to fuchsia colored petals.  相似文献   

15.
Taxonomic changes are made to reflect a reassessment of morphology based on the results of molecular phylogenetic studies. A new genus, Davilanthus, is described to include six species that collectively form the sister group to Simsia, and includes the following species transferred from Viguiera: Davilanthus davilae, Davilanthus hidalgoanus, Davilanthus hypargyreus, Davilanthus huajuapanus, Davilanthus purpusii, and Davilanthus sericeus. Three species formerly placed in Viguiera ser. Grammatoglossae are transferred to Simsia: Simsia benziorum, Simsia ovata, and Simsia rhombifolia.  相似文献   

16.
Symplocos minima, a new species of Symplocos section Hopea from the Itatiaia Plateau in the Atlantic Rain Forest biome of southeastern Brazil, is described and illustrated. This species is distinguished by its densely compact shrubby habit, ascending leaves, fasciculate inflorescences with several persistent bracts, corolla with five to six erect lobes, pistillate flowers with the disc not thickened along the margin, fruiting calyx lobes obscuring the disc, and seeds sub-orbicular in cross section. The new species is morphologically related to S. itatiaiae and S. pentandra, but can be differenciated from them mainly due to the tree habit and fruiting calyx lobes not obscuring the disc in S. itatiaiae and the pistillate flowers with a disc that is thickened along the margin in S. pentandra.  相似文献   

17.
Two new species of Myrtaceae are described and illustrated. Campomanesia cucullata is a tree from Monte Alegre, Pará, in the Brazilian Amazon. It is most similar to C. lineatifolia, from which it differs by being leafless when flowering, and by having densely congested and very small flowers. Myrcianthes monteucalyptoides is a tree from Tarma, Junín, in Central Peru. It is most similar to Myrcianthes myrsinoides, but the new species differs by a combination of medium-sized, somewhat revolute, broadly-acuminate leaves, and by the solitary, pentamerous flowers with delicate pedicels.  相似文献   

18.
Calycogonium formonense, a new species, is here described from the floristically diverse Massif de la Hotte of southern Haiti. It is compared to C. hispidulum, to which it is likely related. Although the genus Calycogonium is not monophyletic, C. formonense and C. hispidulum are probably related to other species, e.g., C. calycopteris, C. heterophyllum, and C. reticulatum, that exhibit reduced inflorescences and 4-merous flowers having hypanthia with four conspicuous lobes separated by longitudinal grooves and external calyx lobes that are flattened parallel to the floral radii. These distinctive species may form a clade. Calycogonium formonense is distinguished from C. hispidulum by its smaller leaves with the tertiary veins not raised on the abaxial surface, with entire margins (i.e., margin without elongate multicellular hairs), and usually solitary flowers.  相似文献   

19.
Burmeistera, Centropogon, and Siphocampylus together comprise more than 500 species endemic to the Neotropics, Current knowledge of these genera is unsatisfactory, with much diversity yet to be described. Over the past seven years, one out of every 28 specimens received for identification has represented a new species, many characterized by unique or unusual character states. Siphocampylus smilax (Bolivia) is unique in the genus in its parallelodromous leaf venation and extra-floral nectaries. Centropogon dianae (Peru) cannot be accommodated in any recognized infrageneric taxon, and a new section, Centropogon sect. Niveopsis, is proposed for it. The flowers of C. steinii (Ecuador) are the smallest known in the genus, while C. connatilobatus (Venezuela) is the first species to combine arbusculiform pubescence and connate calyx lobes. Burmeistera venezuelensis is only the second species of the genus known to occur in Venezuela and the first to be endemic; similarly, Centropogon wilburii is only the third species of Centropogon known from Mexico and the first to be endemic to that country. Additional novelties are also described.  相似文献   

20.
Dolichoura has two species, D. spiritusanctensis and D. kollmannii, the latter described here. The genus can be recognized within the tribe Merianieae by 6-or 7-merous flowers, purple petals, stamens with a dorsal, spiraled appendage at the base of the connective, and seeds with narrow, lateral wings. The new species can be recognized by the suffruticose habit, 4-winged branches, coriaceous leaves with very small petioles and bullate adaxial surfaces, and by the 6-merous flowers.  相似文献   

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