New names and combinations in Trixis (Compositae)

Trixis chiapensis, T. grandibracteata, T. mexicana var.auriculata, T. mexicana var.macradenia, andT. parviflora are described as new, and the combinationsT. californica var.peninsularis, T. michuacana var.longifolia, andT. pringlei var.oligantha are proposed. The application of the namesT. inula andT. michuacana is discussed.     

A Taxonomic study of the calea orizabaensis complex and its bearing on the nomenclature of verbesina standleyi (Asteraceae)

Examination of type material ofVerbesina standleyi andCalea pachyphylla shows that the two taxa are conspecific. The older name,C. pachyphylla, has long been associated with the quite remote,C. orizabaensis. The latter is indistinguishable fromC. rupestris andC. guatemalensis; accordingly, these are placed in synonymy.Calea orizabaensis consists of two infraspecific taxa, var.orizabaensis and var.websteri; the latter is described as new.     

The genus Hymenoclea (Compositae: Ambrosieae)

Two species are recognized within the genus,H. monogyra Torr. & Grayex Gray andH. salsola Torr. & Grayex Gray. Of these, the fall-floweringH. monogyra is monomorphic and unambiguous. The springfloweringH. salsola, however, is polymorphic and contains elements that have often been segregated as distinct species. Examination of character intergradation and interpretation of morphological variation against the evolution and distributional backgrounds indicate that the latter complex is best treated within three varietal taxa:H. salsola var.fasciculata, with wings of the fruiting involucres appressed and spirally arranged;H. salsola var.salsola, with wings emergent and spirally arranged; andH. salsola var.pentalepis, with wings strongly emergent and whorled.     

New taxa in Pectis (Compositae: Pectidinae) from Mexico and the southwestern United States

Pectis minutiflora,P. papposa var.grandis, andP. purpurea var.sonorae are described as new. A new combination,P. purpurea var.lancifolia also is included. Chromosome counts (n = 12) are reported forP. papposa var.grandis andP. purpurea var.sonorae.     

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.     

A new name and new combinations in Campomanesia and Pimenta (Myrtaceae)

One new name is proposed and eleven new combinations are made inCampomanesia andPimenta. Lectotypes are selected forC. eugenioides var.desertorum, C. phaea, andP. racemosa var.hispaniolensis, var.ouza, and var.terebinthina.     

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.     

Genetic Diversity in the Worldwide <Emphasis Type="Italic">Botrychium lunaria</Emphasis> (Ophioglossaceae) Complex,with New Species and New Combinations

The Botrychium lunaria (Ophioglossaceae) complex worldwide includes the named species B. lunaria, B. crenulatum, B. tunux, and B. yaaxudakeit. These species have been distinguished from each other morphologically and genetically. This study further investigates the genetic diversity and geographic distribution of this complex, examining a large number of plants worldwide. Enzyme electrophoresis was used to examine allelic variation of 22 loci for 1574 plants of putative B. lunaria, B. crenulatum and B. tunux from North America, Eurasia, and New Zealand, and B. dusenii from the Falkland Islands. Variation in allelic composition assessed by genetic identity and cluster analysis using the programs PopGene and STRUCTURE as well as morphology and geography indicated that the complex is composed of six distinct entities; two of which warrant recognition as new species, B. neolunaria, endemic to North America, and B. nordicum, sister to the B. lunaria complex, from Iceland and Norway; and a new combination, B. lunaria var. melzeri , endemic to Greenland, Iceland, and Norway. The new taxa are described in this paper. Three entities within B. tunux are discussed but not proposed for recognition at this time. Botrychium lanceolatum, included in this study, is composed of three morphologically and genetically distinct entities warranting taxonomic recognition.     

The taxonomy of eriodon and notes on other South American genera of brachytheciaceae with erect capsules

Eriodon is reduced from five species to two.Eriodon radicalis is recognized asEntodontopsis radicalis;Eriodon longipes asPorotrichodendron longipes; andE. brevisetus as synonymous withLindigia debilis. Mandoniella, Stenocarpidiopsis andLepyrodontopsis are discussed and illustrated.Lepyrodontopsis is transferred to the new familyLe pyrodontopsidaceae, near the Meteoriaceae. The following nomenclatural trans fers are proposed for Rozea:R. andrieuxii f.chrysea andR. andrieuxii var.bour gaeana. Sciuroleskea is transferred to an alliance withStereophyllum,Juratzkaea, Entodontopsis, Stenocarpidium andJuratzkaeella. The following transfers are proposed:Sciuroleskea roseorum (Williams asRozea) Buck andJuratzkaea argentinica (Thér. asJ. seminervis var.argentinica) Buck. A key to the erect-capsuled South American genera retained in the Brachytheciaceae is provided.     

New species,new records,and neotypification of some Mesoamerican Ericaceae

Cavendishia davidsei Luteyn,Cavendishia gomezii Luteyn, andCavendishia limonensis Luteyn are described as new and their relationships are discussed;C. davidsei andC. limonensis are illustrated.Cavendishia chiriquiensis var.chiriquiensis and var.bullata, Sphyrospermum ellipticum, Themistoclesia horquetensis, and the genusAnthopterus (A. revolutus) are newly reported from Costa Rica;Orthaea brachysiphon is newly reported from Mexico. Belize, and Honduras;Pernettya prostrata is reported here from Honduras; andThemistoclesia costaricensis is verified from Panama.Cavendishia glutinosa (=C. endresii) andEmpedoclesia brachysiphon (=Orthaea brachysiphon) are neotypified.     

A study of morphological variability in chenopodium incanum (Chenopodiaceae) and the recognition of two new varieties

Study ofChenopodium incanum has revealed considerable variability in what has been viewed previously as a uniform species. Variation is correlated with geographic distribution, and thus two new varieties are described. Varietyeatum Crawford occurs in western Texas, southern New Mexico and southern Arizona, whereas var.occidentale Crawford is restricted to the Great Basin and Mohave Desert. The var.incanum grows primarily on the western Great Plains and eastern slopes of the Rocky Mountains. Morphological features serving to distinguish the varieties are presented and discussed. Also considered are the characters that allow the separation ofC. incanum andC. fremontii.     

Further notes on European taxa of the lichen genus Leptogium,with emphasis on the small species

Abstract:Leptogium imbricatum P.M. Jørg. sp. nov. and L. intermedium (Arnold) Arnold are established as the correct names for two fairly widespread, small species: L. imbricatum has an arctic-alpine distribution. Leptogium intermedium was previously mostly named L. minutissimum (Flörke) Fr., the type of which is L. subtile (Schrader) Torss., a distinct species usually growing on rotting wood or debris. Leptogium magnussonii Degel. & P.M. Jørg, mainly from maritime rock outcrops in Norway and Sweden, is described as new. The species complexes of L. plicatile (Ach.) Leighton and L. schraderi (Bernh.) Nyl. are discussed. The differences between L. byssinum (Hoffm.) Nyl. and L. biatorinum (Nyl.) Leighton are given, and L. aquale (Arnold) P.M. Jørg. comb. nov., a taxon related to the latter, is considered to be a distinct species growing in mountain brooks in Central Europe. Leptogium rivale Tuck. is recorded as new to Europe, from Romania. Leptogium bellopratense Hy is shown to be a synonym of L. brebissonii Mont. New records for L. coralloideum (Meyen & Flotow) Vainio, L. massiliense Nyl and L. rivulare (Ach.) Mont. are given. A preliminary key to the small European species (north of the Alps) is appended. The following names have been lecto- or neotypified: Collema byssinum Hoffm., Collema pulvinatum Hoffm., Leptogium bellopratense Hy., Leptogium crenulatum Watson, Leptogium massiliense Nyl., Leptogium minutissimum var. intermedium Arnold, Leptogium minutissimum f. plumbeum Zwackh ex Arnold, Leptogium pusillum var. aquale Arnold, Leptogium rivulare var. crenatulum Nyl., Leptogium scotinum var. crenatum Nyl., Lichen byssinus Hoffm., Lichen minutissimus Flörke, Lichen schraderi Bemh., Lichen subtilis Schrader and Parmelia scotina var. lophaea Ach.     

Plasmolysis effects and osmotic potential of two phylogenetically distinct alpine strains of Klebsormidium (Streptophyta)

The osmotic potential and effects of plasmolysis were investigated in two different Klebsormidium strains from alpine habitats by incubation in 300–2,000 (3,000) mM sorbitol. Several members of this genus were previously found to tolerate desiccation in the vegetative state yet information was lacking on the osmotic potentials of these algae. The strains were morphologically determined as Klebsormidium crenulatum and Klebsormidium nitens. These species belong to distinct clades, as verified by phylogenetic analysis of the rbcL gene. K. crenulatum is part of to the K. crenulatum/mucosum (‘F’ clade) and K. nitens of the ‘E2’ clade. Plasmolysis occurred in K. crenulatum at 800 mM sorbitol (961 mOsmol kg^?1, Ψ?=??2.09 MPa) and in K. nitens at 600 mM sorbitol (720 mOsmol kg^?1, Ψ?=??1.67 MPa). These are extraordinarily high osmotic values (very negative osmotic potentials) compared with values reported for other green algae. In K. crenulatum, the maximum photosynthetic rate (Pmax) in the light-saturated range was 116 μmol O₂ h^?1 mg^?1 chl a. Incubation in 1,000 mM sorbitol decreased Pmax to 74.1% of the initial value, whereas 2,000 mM sorbitol (Ψ?=??5.87 MPa) lead to an almost complete loss of oxygen production. In K. nitens, Pmax was 91 μmol O₂ h^?1 mg^?1 chl a under control conditions and incubation in 800 mM sorbitol did not decrease Pmax, 2,000 mM sorbitol decreased Pmax only to about 62.6% of the initial value whereas 3,000 mM sorbitol stopped oxygen evolution. This indicated a broader amplitude for photosynthesis in the examined strain of K. nitens. Control samples and samples plasmolysed for 3 h in 800 mM sorbitol (K. nitens), 1,000 mM sorbitol (K. crenulatum), or 2,000 mM sorbitol were investigated by transmission electron microscopy after chemical or high-pressure freeze fixation. In cells undergoing plasmolysis the protoplasts were retracted from the cell wall, the cytoplasm appeared dense, vacuoles were small and fragmented, and the cytoplasm was filled with ribosomes. Thin cytoplasmic strands were connected to the cell wall; 2,000 mM sorbitol increased the effect. The content of soluble carbohydrates in these two strains was investigated by HPLC, as this is one known mechanism for cells to maintain high osmotic pressure of the cytosol. Both Klebsormidium species contained diverse soluble carbohydrates, including a dominant mixed peak of unidentified oligosaccharides, and more minor amounts of raffinose, sucrose, glucose, xylose, galactose, mannose, inositol, fructose, glycerol, mannitol, and sorbitol. The total content of soluble carbohydrates was approximately 1.2% of the dry weight, indicating that this is not a major factor contributing to the high osmotic potential in these strains of Klebsormidium.     

Notes onConocybe (Bolbitiaceae)

The mycological exploration of the Viennese nature preserve Lobau, resulted in the discovery of several new species ofBasidiomycetes; of special interest is the genusConocybe of which the authors present two new taxa:C. lobauensis andC. leporina var.tetraspora. FurthermoreC. neoantipus, C. striatipes andC. caespitosa are discussed, and the new varietiesC. neoantipus var.tucumana and var.carinthiaca as well asC. striatipes var.sejuncta are proposed.     

The experimental verification of natural hybridization between two taxa of Hawaiian Bidens (Asteraceae)

Bidens ctenophylla andB. menziesii var.filiformis are two heterozygous, self-fertile but outcrossing, interfertile taxa. A relatively fertile intermediate population occurs on the “hybridized habitat” of a recent lava flow. This population contains some indi viduals which are similar toB. ctenophylla, some which are similar toB. menziesii var.filiformis, and many individuals of various intermediate forms. Variation studies of greenhouse populations of the two species, the F₁ hybrid, the F₂ hybrid, and the progeny of three wild intermediates confirm the field observation that the wild intermediate population is a product of natural hybridization betweenB. ctenophylla andB. menziesii var.filiformis. The analysis of two interspecific characters, stem anthocyanin and achene awns, indicates that each is polygenic and is regulated by relatively few genes.