Outer Phyllaries Research Articles

A new species and a new combination in the South American genus Lessingianthus (Vernonieae, Asteraceae)

A detailed analysis of the type material of Vernonia oxyodonta clearly indicates that it is morphologically identical to Lessingianthus glabratus because it has glabrous leaves, pedunculate heads at the end of the inflorescence, outer phyllaries with acute apex and inner phyllaries with obtuse and mucronulate apex, and 30–40 florets per head. Consequently, all the specimens identified as V. oxyodonta are placed to a new species, L. pubescens. Also, V. pseudoincana is transferred to the genus Lessingianthus. This species belongs to the L. rubricaulis complex but can be distinguished from the remaining taxa of the group by its lanceolate leaves, grayish phyllaries, and habitat.

Morphology and genome weight of Symphyotrichum species (Asteraceae) along rivers in The Netherlands

The characters used in separating Symphyotrichum species naturalised along rivers in Western Europe (leaf bases more or less clasping, length of outer phyllaries relative to inner ones, hairiness of leaves) hardly apply to the plants found in the wild. We present morphological and cytometric data on 88 plants of Symphyotrichum from riversides in The Netherlands and adjacent Germany, in order to understand better the taxonomy of these plants. Ploidy was inferred from 2C-values obtained by flow cytometry. Inferred tetraploid plants with relatively deeply lobed disc florets (mean lobe/limb ratio .50%), relatively few florets per head (,40), disc florets usually ,4 mm, and small flowering heads are referred to S. ontarionis (Wiegand) G.L. Nesom. Inferred hexaploids and octoploids with relatively deeply lobed disc florets (mean lobe/limb ratio .50%) and relatively many florets per head (.50) are referred to S. aff. lateriflorum (L.) A´.

Saussurea haizishanensis sp. nov. (Compositae, Cardueae) from Sichuan, China

Saussurea haizishanensis B. Q. Xiu, G. Hao & N. H. Xia sp. nov., a new species from Sichuan, China, belonging to Saussurea subg. Eriocoryne (DC.) Hook. f. sect. Cincta Lipsch., is described and illustrated. It is similar to S. delavayi, but differs in its narrowly elliptic, lanceolate or broadly lanceolate leaves, outer phyllaries that are broadly triangular with irregularly dentate margin, and densely yellowish stipitate glandular stem, leaf blades, and adaxial phyllaries. It is also similar to S. schlagintweitii, but differs in possessing numerous capitula and having adaxially glabrous petiole bases. Color plates, line drawings, a distribution map of S. haizishanensis, photographs of phyllaries and leaf blades, and SEM microphotographs of the adaxial surface of style arms, the leaf blades, the abaxial surface of phyllaries of S. haizishanensis and S. delavayi are provided.

New species of <I>Lessingianthus</I> (<I>Asteraceae</I>, <I>Vernonieae</I>) from Brazil and Paraguay

Two new species of the genus Lessingianthus (Vernonieae, Asteraceae) from Brazil and Paraguay are described and illustrated. Lessingianthus cipoensis is characterized by the presence of solitary heads disposed in short branches and ovate to elliptical leaves. It has a certain resemblance to L. vestitus, which has more branched inflorescences, with long branches, and lanceolate to obovate-lanceolate leaves. Lessingianthus paraguariensis is closely related to L. asteriflorus and L. mollissimus, but it can be distinguished by the broadly elliptical leaves and the large size of the outer phyllaries.

Aster chusanensis (Asteraceae), a new species from Korea

Asterchusanensis is described and illustrated, and compared with its most closely related species,A. pseudoglehni andA. spathulifolius. This new species differs markedly from the latter two by its unequal inner and outer phyllaries, pubescent stem, leaves, and corolla tube, and ray florets partly in two series.

Comparative Capitular Morphology and Anatomy of Coreopsis L. and Bidens L. (Compositae), Including a Review of Generic Boundaries

The capitular and floral morphology and anatomy ofBidens L. andCoreopsis L. were studied. All the North American species ofCoreopsis were studied. Selected species ofBidens from North and South America andCoreopsis from South America were included. The results were compared with previous observations on African species ofBidens (incl.Coreopsis). Emphasis was given to character states of the ray florets, paleae, stylearm apices, outer phyllaries, achenes, and pollen grains. Some of the character states are unique features ofCoreopsis, e.g., globular and elongately conical receptacles, deltoid outer phyllaries, truncate and indistinctly 3–5-dentate, 3–4-lobed ray florets, narrowly spathulate paleae, subulate paleae with linear-filiform upper half, hairy and apically 3-cleft paleae, truncate, convex or shallowly conical stylearm apices with the sweeping hairs limited to the area above the stigmatic surfaces and the orbicular to circular achenes. The cylindric setaceous pappus bristles so commonly encountered inBidens are unknown inCoreopsis. The pappus bristles inCoreopsis are paleaceous but similar, though thicker ones are also found in African species ofBidens (incl.Coreopsis) with winged achenes. Twin-celled hairs (setulae) with differing degrees of wall thickness are found on the achenes ofCoreopsis sect.Pseudoagarista (Mexico and South America),Coreopsis sect.Pugiopappus (California), AfricanBidens with winged achenes (e.g.,B. prestinaria, B. macroptera) and some North AmericanBidens (e.g.,B. aristosa). Similar sclerotic parenchyma make up the achenial wings of species in both genera. These may be interpreted as homologous structures, indicating the underlying similarity of these taxa and their derivation from a common ancestral stock.

Meristem geometry and heritable variation in numbers of florets and involucral bracts inMicroseris pygmaea(Asteraceae, Lactuceae)

SUMMARY Strains A92 and C96 of the Chilean annual, Microseris pygmaea, represent the genetically most divergent biotypes within the species. They differ, among other characters, in the numbers of florets and inner and outer phyllaries (involucral bracts) per head. Higher numbers in A92 are mainly the consequence of smaller primordia while the capitulum buds in both strains are about equal in size. Disruptive selection from a large F2 of the hybrid between A92 and C96 has produced lines with transgressive numbers of parts with non-parental correlations among numbers of parts. The early development of the capitula was studied in F4 families derived from two F2 plants selected for extreme organ number phenotypes. Differences in organ numbers among these families are primarily due to differences in capitulum size which did not differ significantly between the parental strains. Values for other parameters such as floret primordium size, height of the zone in which inner phyllaries arise, and difference in size between peripheral and central florets, did not significantly contribute to the observed differences in organ numbers. The multiple gene differences suggested by the transgressive segregation in the F2 can be partly traced back to various primary effects on meristem differentiation.

A New Agoseris (Asteraceae) from Idaho and Montana

A new species, Agoseris lackschewitzii, is described and illustrated. Morphologically it is similar to both A. aurantiaca and A. glauca but differs notably from both in having pink flowers. It further differs from A. aurantiaca in characters of the fruit and outer phyllaries, and from A. glauca in characters of the anthers and outer phyllaries. Additionally, A. lackschewitzii is restricted to perennially wet montane meadows of southwestern Montana and adjacent Idaho, habitats where other species of this genus are not encountered within this region.

THE HYBRID ORIGIN OF ASTER ASCENDENS (ASTERACEAE)

Aster ascendens Lindl. is a rhizomatous perennial of the Great Basin region of the western United States, with a chromosome base number of x = 13. Populations in the southern and western parts of the range are mainly diploid (n = 13) and those in the north and east are mainly tetraploid (n = 26). This species is postulated to be an amphiploid which has resulted from hybridization between the western Cordilleran A. occidentalis (T. & G.) Hook, and the Great Plains species A. falcatus Lindl. Aster ascendens is intermediate between these two species in most morphological traits, but resembles A. occidentalis in ray color and general growth habit, and A. falcatus in the shape of the outer phyllaries. The karyotype of A. ascendens also exhibits a combination of the features found in A. occidentalis and A. falcatus karyotypes. Of the specimens collected for this study, 13% were putative backcrosses of A. ascendens to one of its parent taxa or to a closely related species; this suggests that there is potentially continuing genetic interchange between the species groups that gave rise to A. ascendens.

Three New Species of Flourensia (Asteraceae-Heliantheae) From South America

Three new species of Flourensia (Asteraceae-Heliantheae) from South America are described: F. peruviana Dillon and F. polycephala Dillon from central and southern Peru respectively; and F. blakeana Dillon from northcentral Argentina. The genus Flourensia is represented by at least four species in Peru, two of these described for the first time within this paper. Flourensia macrophylla Blake is represented by scattered populations in valleys of various rivers draining into the Pacific along the western slope or Cordillera Occidental from northern to central Peru (2,500-3,500i m). Flourensia angustifolia (DC.) Blake is found in intermontane valleys associated with the tributaries of the Rio Perene and Rio Huallaga in the Cordillera Central (1,700-3,300 m). Flourensia peruviana Dillon and F. polycephala Dillon are distributed in dry sites in valleys with eastern drainage from southcentral and southern Peru. Flourensia heterolepis Blake is represented by scattered populations in the Cordillera Real of southeastern Bolivia (ca. 2,700 m), a distance of ca. 725 km from the southeastern Peruvian taxa. Each species is readily distinguished by a complement of morphological characters and a distinct geographical distribution. The distributional pattern of these taxa corresponds with regions postulated to have undergone a series of humidarid cycles during the Quaternary, which drastically and repeatedly altered vegetation patterns (Vuilleumier, 1971; Simpson, 1975). While it is difficult to accurately determine when and how these taxa attained their present distributions, a rather recent radiation is suggested. A similar pattern of species distribution is exhibited in other taxa occupying various habitats in the Peruvian Andes (Simpson, 1975). An additional example is found in Tecoma (Bignoniaceae) (Gentry, 1979) which has unique taxa in each of the major valleys similarly occupied by different Flourensia species. The following key compares the salient differences between all the Flourensia species of Peru and adjacent Bolivia. Figure 1 illustrates the distribution of these species. la. Leaves shallowly denticulate. 2a. Leaves oval to oblong-oval, the apex obtuse to subobtuse -F. macrophylla 2b. Leaves lanceolate to narrowly-elliptic, the apex acute -F. angustifolia lb. Leaves strictly entire. a. Outer phyllaries 2-3 mm long, the inner 3-5 mm long, all ca. 1.5 mm wide F. peruviana 1 I thank Dr. W. G. D'Arcy for providing the Latin descriptions, and Dr. A. Gentry for reviewing the manuscript. I wish to acknowledge the support of field work by an N.S.F. predoctoral dissertation improvement grant and the N.S.F. Flora of Peru grant. Illustrations were prepared by Elizabeth Liebman, Exhibition Department, Field Museum of Natural History. 2 Botany Department, Field Museum of Natural History, Roosevelt Road at Lakeshore Drive, Chicago, Illinois 60605, U.S.A. ANN. MISSOURI BOT. GARD. 68: 105-111. 1981. 0026-6493/81/0105-011 1/$0.85/0 This content downloaded from 157.55.39.235 on Fri, 07 Oct 2016 06:03:54 UTC All use subject to http://about.jstor.org/terms 106 ANNALS OF THE MISSOURI BOTANICAL GARDEN [VOL. 68 A X . * Flourensia macrophylla

Notes on East African Vernonieae (Compositae)

Summary. A second species of Rastrophyllum is described. 9 species are transferred from Erlangea and Triplotaxis to Bothriocline and Gutenbergia. A different neotype is proposed for Bothriocline pectinata. 1. A new species of Rastrophyllum Rastrophyllum apiifolium M.G. Gilbert sp. nov. a R. pinnatipartito Wild & Pope, specie hactenus sola generis, foliis petiolis expansis lobis latioribus manifeste dentatis, capitulis grandioribus paucioribus, phyllariis exterioribus praecipue in marginibus pilosis, phyllariis interioribus marginibus scariosis latis apicibus aristatis recurvis differt. Typus: Tanzania, Mutch in MRC 94 (holotypus EA). Erect, pungently scented herb to 75 cm high, base unknown but plant probably annual, all parts except flowers with globose trichomes and septate hairs with, when dry, basal cells whitish and the terminal cell very elongated, yellowish. Stem cylindrical, striate, sparsely hirsute, branching above. Leaves alternate, petiolate, petiole up to 2 cm long, expanded into a broad amplexicaul base up to 0-8 cm wide, sometimes in upper leaves the amplexicaul base supported by a narrower parallel-sided section up to 0-5 cm long; blade elliptic in outline, deeply pinnatisect, the lobes with such prominent teeth that the blade is almost bipinnatisect, up to 6 x 4 cm (probably larger at base, these leaves withered in only collection seen), 10-15 lobes per side, lobes c. 0-6 cm wide overall, the marginal teeth up to 2 mm high, 2 mm apart, upper surface glabrous except for densely pilose main vein, secondary and tertiary veins deeply impressed, lower surface densely pilose on all veins, globose trichomes between veins. Inflorescence a terminal corymbose cyme of up to 5 capitula, often subtended by leaf-like bracts with particularly conspicuously expanded petioles and rather reduced leaf blade. Peduncles up to 2-5 cm long, often ebracteolate, densely brown-pilose. Involucre broadly campanulate to slightly urceolate, 2-3-seriate, at anthesis 7 x c. 15 mm; outer phyllaries ovate, c. 6-5 x 2 mm, basal half indurated, glabrous, pale, apical half foliaceous, hairy, especially along margins and along centre-line; inner phyllaries oblong-lanceolate, acuminate, c. 8-5 x 2-2 mm, with broad scarious, slightly fimbriate, margins and a slightly reflexed, aristate tip. Corolla pale mauve, 9 mm long overall, shortly cylindrical at base, then uniformly narrowly infundibuliform; lobes 3 x 0-4 mm; with globose trichomes throughout and short gland-tipped hairs towards base. Anthers 1-8 x 0-15 mm after dehiscence, with 0-3 mm long hyaline apical appendage

Two New Species of Conyza (Compositae) from Ethiopia

A herb with leafy stems, the vegetative parts (when dry) tawny-green and shortly scabrid-pubescent throughout. Inflorescence of terminal and axillary cymose panicles of 5-15 capitula, the capitula fairly loosely arranged on pubescent peduncles bearing hairs up to 1-5 mm long. Involucre hemispherical, composed of several rows of phyllaries. Outer phyllaries elliptic, obtuse to acute, nearly entirely herbaceous, brownish-green, with about 6 longitudinal resinous vein-like lines in addition to the only slightly more prominent midrib, the central part of the phyllary with a few scattered sessile glands and a dense pubescence of white hairs 1 mm long. Inner phyllaries narrowly oblong, acute, hyaline with a central brown herbaceous stripe. Receptacle barely fimbrillate. Female florets very many, filiform, 3-1 mm long, of which 1 mm is a pale yellow bifid ligule shorter than the yellow style, the top of the corolla tube with a fringe of multicellular hairs. Achenes of female flowers fertile, obovoid, compressed, 2-ribbed, pilose. Hermaphrodite flowers c. 20, 4 mm long, with a short basal tube 1-5 mm long and a wider portion 2-5 mm long, at the apex with 5 lobes, the tube and lobes bearing both multicellular hairs and sessile glands. Achenes of hermaphrodite flowers apparently fertile, larger than those of the female flowers, often 4-ribbed, pilose. Pappus of about 25 hairs in 1 row, including about 5 very short bristles.