The genus hampea(Malvaceae)

The genusHampea Schlecht. is included in the Malvaceae, tribe Gossypieae, rather than in the Bombacaceae where it was originally placed. Discussion includes the morphology, geography (central Mexico to western Colombia), reproductive cycle, utilization and vernacular names, and cytology (n = 13) of the genus. Three species have perfect flowers; the remainder are dioecious. The 16 species (and one variety) that are accepted are divided into three sections, one of which is further subdivided into three series. The following taxa are described as new:H. nutricia, H. mexicana, H. sphaerocarpa, andH. appendiculata var.longicalyx.     

New species and combinations in Vernonia sections Leiboldia and Lepidonia (Asteraceae), with a revisional conspectus of the groups

The wholly North American sectionLeiboldia ofVernonia as revised by Jones (1979) included six species. The present treatment recognizes only three species inLeiboldia, including one newly described from recent collections. The remainder of what Jones consideredLeiboldia has been transferred into a new sect.Lepidonia (Blake) Turner which was first proposed as a monotypic genus. A key to the two sections and 10 species is provided along with an account of their interrelationships. Morphological evidence suggests that sect.Lepidonia is one of the more primitive sections ofVernonia, being as close to certain African sections as they are to the mostly American sect.Vernonia. Consideration is given to the phyletic significance and generic value of receptacular pales in the Vernonieae from which it is concluded that these have persisted in three or more quite unrelated lines of this tribe and undue weight should not be accorded these in generic considerations. Consequently, the paleaceous, monotypic generaLepidonia andBolanosa are sunk into synonymy underVernonia, the former as a distinct section, the latter into the sect.Vernonia.     

The subdivisions of Magnistipula Engl. (Chrysobalanaceae)

A conspectus of the subgenera and sections ofMagnistipula is provided. Of the two subgenera occurring on the African mainland, subgenusMagnistipula is divided into the sectionsMagnistipula,Animalculum andPeregrinator, whereas subgen.Pellegriniella is monotypic. A Malagasy subgenus,Tolmiella, is new; its two species,M. cerebriformis andM. tamenaka, are transferred fromHirtella.     

Taxonomic studies in the Miconieae (Melastomataceae). I. Variation in inflorescence position

In the Miconieae (Melastomataceae) the inflorescences may be either lateral (with shoots pleonanthic and plants showing Rauh's architectural model) or the terminal (with shoots hapaxanthic and plants illustrating Leeuwenberg's, or less commonly Scarrone's or Stone's, architectural models). Inflorescence position is a valuable taxonomic character in the tribe and is usually uniform within genera or speciesgroups. An analysis of variation of this character elucidates the complex and difficult generic delimitations within the tribe.Ossaea DC. andClidemia D. Don, as presently delimited, contain both terminal-and axillary-flowered species and are undoubtedly polyphyletic assemblages. Some groups, e.g.,Clidemia sect.Clidemia, Leandra Raddi sect.Chaetodon Cogn.,Ossaea sect.Octopleura (Griseb.) Cogn., andMyrmidone Mart. have species that develop pseudolateral inflorescences, i.e., the terminal nature of the inflorescence is obscured by the early development of an axillary bud which continues growth of the branch. Pseudolateral inflorescences seem to have evolved several times within the tribe, andClidemia sect.Clidemia likely evolved from the obviously terminal-floweredHeterotrichum DC. andMiconia Ruíz & Pavón sect.Octomeris Hook. f. (p. p.);Myrmidone andMicrophysca Naud. are closely related toTococa Aublet; andLeandra sect.Chaetodon (and probably alsoOssea sect.Octopleura) show affinity with the remaining sections ofLeandra.     

Revision of the genus Clibadium (Asteraceae, Heliantheae)

Clibadium L. (Asteraceae, Heliantheae) is a genus of 29 species distributed throughout latin America, from Mexico to Peru, and in the West Indies, with high numbers of species in Costa Rica, Colombia, and Ecuador.Clibadium includes shrubs and small trees; usually with loosely aggregated capitula; herbaceous phyllaries arranged in 1–5 series; receptacles usually paleaceous throughout; corollas of pistillate florets 2–4-lobed; corollas of the staminate florets 4–5-lobed; purple to black anthers; and chromosome numbers alln=16. Two sections of species previously recognized are here considered as subgenera (subg.Paleata and subg.Clibadium) containing two and four sections, respectively.Clibadium subg.Paleata contains five species distributed in sects.Eggersia (3 spp.) andTrixidium (2 spp.), and subg.Clibadium has 24 species distributed among sects.Clibadium (6 spp.),Glomerata (9 spp.),Grandifolia (5 spp.), andOswalda (4 spp.).     

Comparative floral morphology in Lycieae (Solanceae)

Comparative organography (excepting carpels studied previously) and anatomy of the flower are reported for some American members of the genera of Lyciaeae:Lycium, Grabowskia, andPhrodus. Data obtained are mostly new since no comprehensive floral anatomical work has been carried out in the tribe. These results include the first report of extrafloral nectaries on the inner epidermis of the calyx inPhrodus andGrabowskia. Results are discussed and compared with previous reports for the family, older than the exclusively AmericanPhrodus andGrabowskia. Lycium shows great morphological diversity while the other two genera are less variable but have more specialized features. A key, based on floral characters, to the genera, of Lycieae and sections ofLycium is provided.     

Taxonomy of carex sect. atratae (cyperaceae) in the southern rocky mountains

The sectionAtratae is highly differentiated in the southern Rocky Mountain region where the group has developed several endemic species. Eleven species are recognized, and three new combinations are proposed:C. parryana ssp.hallii, C. parryana ssp.idahoa, andC. norvegica ssp.stevenii.     

Convolvulus grandiflorus Jacq. (Convolvulaceae) re-examined

Convolvulus grandiflorus Jacq. has been treated as a synonym ofOperculina ventricosa andStictocardia tiliifolia. It is here accepted as identifiable withIpomoea (sect.Calonyction)macrantha which is the correct name for Jacquin’s taxon. Full synonymies ofIpomoea macrantha andOperculina ventricosa are given, along with a comment about a variant occurring in Micronesia.     

Clarification of the status of Hibiscus (sect. Furcaria) uncinellus (Malvaceae)

Hibiscus uncinellus andH. bifurcatus have been confused in the literature and in the herbarium. The morphological, ecological, and geographic differences between them are presented, and a lectotype is chosen for the former species.Hibiscus uncinellus is virtually confined to Mexico (plus one Guatemalan station), andH. bifurcatus occurs in the West Indies, South America, and Central America, as far north as Honduras.     

Hybridization betweenPsidium guajava andP. guineense (Myrtaceae)

Psidium guajava andP. guineense are characterized, illustrated and contrasted. Population samples ofPsidium guajava andP. guineense and apparent hybrids were collected from four localities: two in Mexico, one in Honduras, and one in Argentina. Seven morphological characters, one micromorphological (stomatal density), and one chemical character (presence or absence of myricetin) that distinguish the parent species were found to be useful in the evaluation of specimens and population variation. Results were consistent with the hypothesis that hybridization occurs between these species, but in three localities it may not go beyond Fl ’s. Back crossing between hybrids andP. guajava was not detected at any locality.     

Population studies in Goodyera (Orchidaceae) with emphasis on the hybrid origin of G. Tesselata

Morphological, cytological, and paper Chromatographic studies of populations from northern Michigan and examination of herbarium specimens from throughout North America were used to clarify the relationships ofGoodyera oblongifolia, G. repens var.ophioides, andG. tesselata. A canonical analysis of morphological data from mixed populations of these three species depictsG. tesselata as intermediate betweenG. oblongifolia andG. repens var.ophioides. The latter two species are diploid (2n = 30) andG. tesselata is tetraploid (2n = 60). Triploids (2n = ca. 45) were found in two mixed-species populations in northern Michigan.Goodyera tesselata produces three phenolic compounds present inG. oblongifolia and five different compounds present inG. repens var.ophioides. The range ofG. tesselata is confined to glaciated territory (except for two stations) in northeastern North America where the postglacially produced ranges ofG. oblongifolia andG. repens var.ophioides overlap. However,G. tesselata is quite abundant in areas outside the region of sympatry of the other two species. Based on this evidence, it is postulated thatG. tesselata is an allotetraploid species which resulted from hybridization betweenG. oblongifolia andG. repens var.ophioides during early post-Pleistocene. The slightly earlier blooming season ofG. tesselata may have been selected for to provide a measure of reproductive isolation between the tetraploid and its parents and to adapt the new species to the rather short growing season of northeastern North America.     

Notes on Couepia and Hirtella (Chrysobalanaceae)

Three new species of Chrysobalanaceae from South America are described:Couepia bernardii, Hirtella barnebyi andH. confertiflora. TheCouepia guianensis complex is discussed, redefined and divided into three subspecies that include material previously recognized as separate species. Observations are also made on recent collections of three poorly known species ofHirtella, H. araguariensis,H. dorvalii andH. leonotis.     

Nuclear DNA content variation within the genusTaraxacum (Asteraceae)

Nuclear DNA content was estimated using flow cytometry in 13 sections represented by 18 species of the genusTaraxacum using propidium iodide as the DNA stain. Investigated plants represented diploid, triploid and tetraploid species from sections considered both primitive and advanced, i.e.,T. sect.Dioszegia, Piesis, Glacialia, Mongolica, Scariosa, Obovata, T. pyrenaicum group,T. sect.Coronata, Palustria, Taraxacum (=Crocea),Kashmirana, Ruderalia andErythrosperma. Estimated nuclear 2C DNA content ranged from 1.74 pg in diploidT. linearisquameum (T. sect.Ruderalia) to 6.91 pg in tetraploidT. albidum (T. sect.Mongolica), demonstrating 3.97-fold variation. The lowest monoploid genome size 1C_x=0.87 pg was recorded inT. linearisquameum (T. sect.Ruderalia) together withT. brachyglossum (T. sect.Erythrosperma), and the highest one (1.73 pg) was recorded inT. albidum (T. sect.Mongolica), giving a 1.99-fold difference in the genus. No significant differences in genome size were observed withinT. sect.Ruderalia, similarly no intraspecific variation was observed inT. paludosum (T. sect.Palustria) andT. serotinum (T. sect.Dioszegia). These results indicate a high intraspecific stability of the trait. Preliminary comparisons of genome size in species/sections considered to be close relatives were made. These data give tentative additional evidence for the close phylogenetic relationship between sectionsPalustria andPiesis and against the close relationship between sectionsPiesis andDioszegia.     

The systematics ofLinum sect.Linopsis (Linaceae)

SectionLinopsis of the genusLinum is the largest and probably the most widespread of the five commonly recognized sections. Using a number of traits, but especially heterostyly, style union, development of false septa in the fruit, pollen morphology, and chromosome number, together with petal pigmentation, number of floral parts, and stigma shape, the section is divided into five subsections:Dichrolinum, with one series;Halolinum with one;Linopsis, with four;Keniense, with one; andRigida, with two. Of these, subsect.Keniense and two series are new, the remaining four subsections and four series are published in a new rank. The inferred relationships of all of the groups and the general distribution of each are discussed. The section ranges from southern Europe and the Mediterranean region to India, eastern and southern Africa and throughout much of North and South America. The primitive species of the section are believed to be in the Mediterranean region.     

Castilleja (Scrophulariaceae) of Costa Rica and Panama

The mountains of Costa Rica and western Panama constitute a natural floristic region that is inhabited by six species ofCastilleja.Castilleja talamancensis, C. lentii andC. tayloriorum are described as new. The remaining three areC. arvensis,C. irasuensis andC. quirosii. All butC. arvensis are endemic to the area. The six species are keyed, described, illustrated, mapped and documented with literature and specimen citations.     

Floral morphology to discriminate taxa between and within Cytisus sect. Alburnoides, sect. Spartopsis and sect. Verzinum (Genisteae, Fabaceae)

Delimitation of sections is controversial within the genus Cytisus L. (Fabaceae, Genisteae). A morphological study has been conducted on 19 taxa from sections Alburnoides, Spartopsis and Verzinum to clarify their discrimination. Thirty-five quantitative and qualitative characters were recorded on a maximum of 15 dry or living flowers per taxon. Three multiple correspondence factor analyses (MCFA) were performed on a matrix based on 22 of the 35 recorded morphological characters to (1) compare the variability within and between individuals and (2) distinguish groups among the studied taxa. MCFA showed that both flowers sampled from the same plant or different individuals could represent the morphological variability of a taxon. MCFA also clustered the 19 taxa into three groups corresponding to sections Alburnoides, Spartopsis and Verzinum as defined by Cristofolini and Troia (Taxon 44:733–746, 2006). However, floral morphology has not been sufficient to discriminate taxa within sections. A key of the three studied sections based on floral characters is given.