Notes on some South American species of Psychotria subgenus Heteropsychotria (Rubiaceae), with observations on rubiaceous taxonomic characters

During the preparation of a treatment of the Rubiaceae for theGuide to the Vascular Plants of Central French Guiana, several field and laboratory observations have contributed toward a better understanding of the morphological variation of certain species ofPsychotria and have stimulated a reevaluation of some morphological features used by previous authors in distinguishing taxa in thePsychotria. Typification for all taxa is provided, several new synonyms and one new combination,Psychotria carapichea (Poir.) Delprete, are proposed, and illustrations ofP. ligularis andP. carapichea are included.     

<Emphasis Type="Italic">Carapichea lucida</Emphasis> (<Emphasis Type="Italic">Rubiaceae: Psychotrieae</Emphasis>), a new species from Eastern Bahia,Brazil

A new species of Carapichea was discovered in the Atlantic Forest of Bahia, Brazil. Carapichea lucida J. G. Jardim &; Zappi is described, illustrated, and its phenology, habitat and conservation status are discussed.     

Agouticarpa, a new neotropical genus of Tribe Gardenieae (Rubiaceae)

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.     

Mitracarpus longicalyx (Rubiaceae, Spermacoceae), a new species from northeastern Brazil

Mitracarpus longicalyx is here described and illustrated from sandy areas of the caatingas of northeastern Brazil. The new species is similar toM. hirtus andM. megapotamicus.     

Riodocea (Rubiaceae, Gardenieae), a new genus from the Brazilian Atlantic forest

The genusRiodocea is here described from material collected in the várzea forest of the Rio Doce Valley, northern Espírito Santo.Riodocea is a monotypic genus probably related to the Amazonian endemicKutchubaea. A line drawing shows general morphology and photomicrographs show pollen morphology ofRiodocea pulcherrima. Distribution maps ofRiodocea andKutchubaea are included. The valley of the Rio Doce is here included in the Bahian Hylaea, defined as a subregion of the Brazilian Atlantic forest. The connections between the Amazonian Hylaea and the Bahian Hylaea are discussed.     

A new species of Remijia (Rubiaceae) from Amazonian Brazil

Remijia hubbardiorum B. M. Boom, endemic to white sandcampinas orerra firme forest in the Rio Uatumã region in the State of Amazonas of north central Brazil, is described and illustrated, and its morphological differentiation with respect toR. asperula Standley is discussed.     

Review of the neotropical endemics Burmeistera, Centropogon, and Siphocampylus (Campanulaceae: Lobelioideae), with description of 18 new species and a new section

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.     

Terpenoids and a coumarin from aerial parts of Psychotria vellosiana Benth. (Rubiaceae)

The phytochemical investigation of Psychotria vellosiana aerial parts yielded five compounds, including two triterpenes (squalene and lupeol), two steroids (stigmasterol and sitosterol), and one coumarin (scopoletin). The structures of the isolates were established based on analysis of their spectroscopic data and comparison with literature. All metabolites isolated were previously detected in Psychotria, excepting squalene that is being described for the first time from this genus. This study adds a new species to a number of reports showing the absence of alkaloid in Psychotria.     

Components of pollination effectiveness in Psychotria suerrensis,a tropical distylous shrub

In this paper I report components of effectiveness for pollinators of a tropical distylous shrub, Psychotria suerrensis (Rubiaceae), which is visited by a variety of bees, wasps, and butterflies, and by two species of hummingbirds. In the field, I measured the following components of effectiveness: frequency of visits, evenness of visits across plants, and diurnal pattern of visits. I also used flight-cage experiments to compare pollentransfer abilities of euglossine bees and heliconiid butterflies. Euglossine bees visited more frequently, visited earlier in the day, and visited a higher proportion of plants in the population than did other taxa. In flight cage experiments, bees and butterflies transferred similar amounts of pollen overall, but bees transferred significantly more inter-morph (compatible) pollen. For each component measured, euglossine bees appeared to be the most effective pollinators.     

Peratanthe is a synonym of Nertera (Rubiaceae, Anthospermeae)

The two species ofPeratanthe, a genus allegedly endemic to the greater Antilles, are shown to be entirely within the variation range ofNertera granadensis (L.f.) Druce var.granadensis, a widespread, often weedy species.     

Notes on Galianthe (Spermacoceae, Rubiaceae) in the Bolivian flora

Four new species ofGalianthe (G. boliviana, G. chiquitosana, G. sudyungesis, andG. kempffiana) for Bolivia are described and illustrated.Galianthe kempffiana is also known from Brazil.Galianthe laxa andG. bisepala are reported for the first time for Bolivia.     

The occurrence of calyx nodules inPsychotria spp. (Rubiaceae)

Summary The occurrence and structure of calyx nodules in the flowers of two leaf nodulated rubiaceous speciesPsychotria punctata Vatke andPsychotria kirkii Hiern. has been described for the first time at the ultrastructural level. Bacteria, resident in colleter-secreted mucilage in the space between calyx and corolla, invade stomatal pores which develop on the calyx protoderm. The bacteria proliferate in the substomatal cavity and then invade the calyx mesophyll. This invasion is most pronounced inP. punctata where the bacteria even penetrate and enter the cells of the vascular tissue. Although no sheath forms around the calyx nodules, the calyx mesophyll cells surrounded by the bacteria become identical in shape, size and secretory function to the invasive mesophyll cells of leaf nodules. The functional and evolutionary significance of calyx nodulation is discussed.     

Revision and typification of Brazilian Augusta (Rubiaceae, Rondeletieae), with ecological observations on the riverine vegetation of the cerrado and Atlantic forests

A revision of Brazilian Augusta and general comments on the systematics of this genus are presented. The complex taxonomic history of this taxon has caused confusion over its correct nomenclature. The peculiar geographic distribution of Augusta has stimulated field observations and analysis of the ecology of the Brazilian ecosystems where this taxon occurs, which are here presented. The five Brazilian species of Augusta described by Pohl are here treated as ecotypes of A. longifolia. This species has two distinct varieties: var. Longifolia, widespread throughout the Brazilian cerrado, and var. parvifolia, endemic to the Atlantic forest near Rio de Janeiro. Typification, list of representative specimens, and distribution map of A. longifolia are also included.     

Mussaenda yunnanensis sp. nov. (Rubiaceae), a new functionally dioecious species from Yunnan,China

Mussaenda yunnanensis, a new dioecious species of Rubiaceae from Yunnan Province, China, is described and illustrated. The new species can be recognized by its slender stem, congested‐cymose inflorescences and long corolla tubes. Differences between M. yunnanensis and two morphologically similar species (M. pubescens and M. antiloga) are presented. We also provide a key to all dioecious species of Mussaenda in China. The delimitation of the new species is further supported by molecular phylogenetic analyses based on eight plastid loci.     

Relationships, circumscription, and biogeography of Arcytophyllum (Rubiaceae) based on evidence from cpDNA

A cladistic analysis was performed using nucleotide sequence variation in therps16 intron and thetrmL-F region (plastid DNA).Arcytophyllum belongs in a subclade of the tribe Spermacoceae (s.l.) together with the American species presently classified in the generaHedyotis andHoustonia. This subclade is morphologically characterized by cymbiform seeds.Arcytophyllum is the sister group of all AmericanHedyotis andHoustonia and it is suggeste that these latter would be most conveniently treated as a single genus, the correct name of which would beHoustonia.Arcytophyllum should be circumscribed such that it excludesA. serpyllaceum, which is not a member of theArcytophyllum-Houstonia clade but more closely related toBouvardia. The phylogeny that was reconstructed suggests that the ancestral area of theArcytophyllum-Houstonia clade is the South American tectonic plate.     

Novelties in spermacoceae (Rubiaceae) from Bolivia and Paraguay

One new Bolivian species (Borreria pazensis) and three new varieties (Borreria densiflora var.minima, Richardia, scabra var.chacoensis andStaelia virgata var.killeenii) are described and illustrated. The genusDiodella, with three species (D. apiculata comb. nov., D. radula comb. nov., andD. teres), is reported for the first time.Borreria limae, B. wunschmannii, B. scabiosoides var.scabiosoides, andB. scabiosoides var.anderssonii are also reported as new to Bolivia.     

Redefinition of the neotropical genus Anthopterus (Ericaceae: Vaccinieae), including one new species

The taxonomic history of Anthopterus as it relates to Themistoclesia is briefly reviewed. Anthopterus is redefined to include several species formerly placed in Themistoclesia. Two subgenera are established within Anthopterus. Anthopterus costaricensis Luteyn is described as new, and the new combination Anthopterus pterotus (A. C. Sm.) Luteyn is made. A key to the genus, a list of the species currently accepted, and brief notes on distribution and frequency are provided. Most species of Anthopterus are rare and their habitats are endangered.