Germination rate and sporeling development of Chondracanthus chamissoi (Rhodophyta, Gigartinales) varies along a latitudinal gradient on the coast of Chile

Chondracanthus chamissoi (C. Agardh) Kutzing is an economically important red seaweed with an extended latitudinal distribution along the south-east Pacific. Here we report on the seasonal in vitro germination of carpospores and tetraspores from four populations distributed from 27 to 41 degrees S on the Chilean coast. Our results show that both types of spores exhibited a different physiological behavior related to the geographic origin of the specimens. Germination occurred throughout the year for both spore types in the four populations. However, for the northern locations (Calderilla, La Herradura and Puerto Aldea) germination was higher in spring, while for the southern location (Lechagua), germination was higher in summer. The growth rate of carposporelings and tetrasporelings varied seasonally in ail locations studied, with higher growth in spring. Among all, carposporelings from Lechagua specimens reached the highest growth rates (9.3 +/- 0.2% d(-1)). However, spores from Herradura and P. Aldea had a good germination and SGR in all seasons and would be good candidates to start spores-based cultivation of this valuable resource in Chile. (C) 2009 Elsevier B.V. All rights reserved

Palisada flagellifera (Ceramiales, Rhodophyta) from the Canary Islands, Spain: a new record for the eastern Atlantic Ocean based on morphological and molecular evidence

Palisada flagellifera (Ceramiales, Rhodophyta) is recorded for the first time in the eastern Atlantic Ocean off Tenerife, La Gomera, La Palma and Fuerteventura, Canary Islands, Spain. The specimens were collected in 2006-2009 growing from the lower intertidal to subtidal zones to 2 m depth at sites exposed to wave action. The species possesses a palisade-like arrangement of cortical cells in cross section, lacks secondary pit connections between them, and has tetrasporangia produced by three fertile pericentral cells (the third and the fourth additional and the second that becomes fertile), and a right-angled arrangement of tetrasporangia. Gametangia were not observed. The phylogenetic relationships were inferred by analyses of the chloroplast-encoded rbcL gene sequences from 46 taxa. The Canarian and Brazilian P. flagellifera specimens formed a highly supported clade with a low level of genetic variation in the rbcL sequences (0.02-0.04%), confirming that they are the same taxonomic entity. This study expands the geographical distribution of P. flagellifera to the eastern Atlantic Ocean.

Wide-band tracheids (WBTs) of photosynthetic and non-photosynthetic stems in species of Cactaceae

ARRUDA, E. AND G. F. A. MELO-DE-PINNA (Departamento de Botanica, Instituto de Biociencias. Universidade de Sao Paulo, Rua do Matao, travessa 14, Cidade Universitaria, Butanta, Caixa Postal 11461, 05422-970. Sao Paulo, SP, Brasil). Wide-band tracheids (WBTs) of the photosynthetic and non-photosynthetic stems in species of Cactaceae. J. Torrey Bat. Soc. 137: 16-29. 2010.-The absence of WBTs and wood polymorphisms in some species of the Caryophyllales may be related to the particular area of plant analyzed. The present research has the objective of studying the photosynthetic and non-photosynthetic stems of different species and stages of differentiation to register wood polymorphisms and to understand the distribution and occurrence of WBTs. Wood polymorphism was observed in the non-photosynthetic stern of young and adult plants of Opuntioideae and Cactoideae and is also found in the photosynthetic stem of young plants of some species of Cactoideae. Cactoideae present WBT/fibrous dimorphic wood that can be related to cambial variation associated with growth habits and plant development. As expected, in the photosynthetic stem of the adult columnar cacti the wood is monomorphic fibrous in which WBTs were not found. This wood contains a great amount of fibers due to necessity of the mechanical support. In contrast, the globular species do not possess fibers in this area of the stem in either adult or young plants. Opuntia monacantha Haw. had non-fibrous wood in which WBTs were observed in the axial system and in the inner parts of the rays. Fiber clusters were present in the axial system. This wood represents a variation in the wood types described for Opuntioideae. Also, in O. monacantha, cells similar to the WBTs were observed in the pith, which can be interpreted as variation in the morphogenic processes during the ontogeny of the plant, probably a case of homeosis. Monomorphic fibrous wood without WBTs was found along the entire stem of Pereskia bahiensis Gurke. This feature has been observed in other pereskias, and in addition to the others, indicates its proximity to the ancestral cacti.

Stigmatic surface in the Vochysiaceae: reproductive and taxonomic implications

(Stigmatic surface, reproductive biology and taxonomy of the Vochysiaceae). The Vochysiaceae are Neotropical trees and shrubs, common in the savanna areas in Central Brazil (Cerrados). The family has been traditionally divided into two tribes: Erismeae, with three genera, and Vochysieae, with five genera. We investigated the stigmatic surface of six Vochysiaceae species, belonging to four genera of Vochysieae: Vochysia, Salvertia, Callisthene and Qualea. Flowers and buds at different developmental stages were collected. Morphological features were observed on fresh material and stigmatic receptivity was inferred based on esterasic activity. Pistils were fixed and embedded in paraplast and sectioned on a rotary microtome; the sections were stained before histological analysis. Stigmas of open flowers were also observed by scanning electron microscopy. Stigmas of all species were wet and showed esterasic activity at pre-anthesis and anthesis stages. Stigmatic surface was continuous with transmitting tissue of glandular nature. Vochysia and Salvertia stigmatic surfaces were formed by multicelular uniseriate hairs, and species of the remaining genera showed papillate surface. The exudate over mature stigmas in all species flowed without rupture of stigmatic Surface and pollen tubes grew down between hairs or papillae. Differences on the stigmatic surface agreed with a phylogenetic reconstruction that separated two clades and indicated that Vochysieae is not monophyletic. Stigmatic features could not be associated with pollination and breeding systems.

Structural aspects of the zygotic embryogenesis of Acca sellowiana (O. Berg) Burret (Myrtaceae)

(Structural aspects of the zygotic embryogenesis of Acca sellowiana (O. Berg) Burret (Myrtaceae)). Acca sellowiana has anatropous, bitegmic and crassinucellate ovules. The outer and inner integuments are double-layered except in the micropyle, where they are composed of more layers; the micropyle is zig-zag shaped. The egg apparatus lies at the micropylar pole, and the zynergids present a conspicuous filiform apparatus. The antipodal cells are present in the chalazal region, persisting before the occurrence of double fertilization. The zygote is visible 21 days after pollination; nuclear endosperm is already present. The first mitotic division of the zygote occurs at 24(th) day. The globular, cordiform and torpedo embryo stages can be seen at 30, 45 and 60 days after pollination, respectively. The mature embryo characterized by the presence of a well-developed hypocotyl-radicular axis with two fleshy and folded cotyledons was observed 120 days after pollination. Endosperm is absent in the seeds, and the embryo has spiral form, characteristic of Myrtinae. The zygotic embryology studies of A. sellowiana indicate that this species has embryological characteristics which are in agreement with those reported for Myrtaceae (Myrteae, Myrtinae), and also broaden the knowledge about the sexual reproduction of this native species, whose commercial cultivation has been growing.

Growth rate differences between four Chilean populations of edible seaweed Chondracanthus chamissoi (Rhodophyta, Gigartinales)

The effects of temperature, photon flux density and photoperiod on the growth rate of female gametophytic and tetrasporophytic thalli of Chondracanthus chamissoi from four populations along the Chilean coast were studied in vitro. Both reproductive phases survived and grew under all the conditions tested, with growth rates varying between 0.1 and 7.5% day(-1). The results showed higher growth rates with increases in temperature and photon flux density levels. The growth rate was higher in female gametophytic thalli in almost all treatments. The photoperiod did not cause significant differences in the growth rate for either reproductive phases in any of the populations studied. Temperature was the principal factor affecting the growth rate of C. chamissoi.

Relief influence on tree species richness in secondary forest fragments of Atlantic Forest, SE, Brazil

(Relief influence on tree species richness in secondary forest fragments of Atlantic Forest, SE, Brazil). The aim of this work was to explore the relationship between tree species richness and morphological characteristics of relief at the Ibiuna Plateau (SE Brazil). We sampled 61 plots of 0.30 ha, systematically established in 20 fragments of secondary forest (2-274 ha) and in three areas within a continuous secondary forest site, Morro Grande Reserve (9,400 ha). At each plot, 100 trees with diameter at breast height > 5 cm were sampled by the point centered quarter method, and total richness and richness per dispersal and succession class were obtained. The relief was characterized by the mean and variance of slope, elevation, aspect and slope location. There was no significant relationship between relief heterogeneity and tree species richness. Relief parameters generally did not affect tree richness, but elevation was particularly important especially in the continuous forest. Despite the limited range of altitudinal variation (150 m), species richness increases with elevation. The highest areas were also those with the largest forest cover and the lowest disturbance degree, which should contribute to the greater richness of those sites. Our results suggest an indirect influence of relief, due to the fact that deforestation is less intense in higher regions, rather than a direct influence of abiotic factors related to the altitudinal gradient.

Successional stage and geographic features determine floristic similarity among Atlantic Forest remnants, Sao Paulo State, Brazil

Analysis of floristic similarity relationships between plant communities can detect patterns of species occurrence and also explain conditioning factors. Searching for such patterns, floristic similarity relationships among Atlantic Forest sites situated at Ibiuna Plateau, Sao Paulo state, Brazil, were analyzed by multivariate techniques. Twenty one forest fragments and six sites within a continuous Forest Reserve were included in the analyses. Floristic composition and structure of the tree community (minimum dbh 5 cm) were assessed using the point centered quarter method. Two methods were used for multivariate analysis: Detrended Correspondence Analysis (DCA) and Two-Way Indicator Species Analysis (TWINSPAN). Similarity relationships among the study areas were based on the successional stage of the community and also on spatial proximity. The more similar the successional stage of the communities, the higher the floristic similarity between them, especially if the communities are geographically close. A floristic gradient from north to south was observed, suggesting a transition between biomes, since northern indicator species are mostly heliophytes, occurring also in cerrado vegetation and seasonal semideciduous forest, while southern indicator species are mostly typical ombrophilous and climax species from typical dense evergreen Atlantic Forest.

Anchietea ferrucciae (Violaceae), a new species from the Brazilian Caatinga

A new species of Anchietea (Violaceae) is described and illustrated. Anchietea ferrucciae is characterized by its 4-carpellate ovary, small flowers and mostly, by its obovate seeds, cuneate at the base, and with a narrow, toothed wing. The new species is narrowly endemic to a very restricted area of the dry Caatinga in Bahia state (Brazil). An identification key to the species of Anchietea is provided.

Five vicarious genera from Gondwana: the Velloziaceae as shown by molecules and morphology

Background and Aims The amount of data collected previously for Velloziaceae neither clarified relationships within the family nor helped determine an appropriate classification, which has led to huge discordance among treatment by different authors. To achieve an acceptable phylogenetic result and understand the evolution and roles of characters in supporting groups, a total evidence analysis was developed which included approx. 20 % of the species and all recognized genera and sections of Velloziaceae, plus outgroups representatives of related families within Pandanales. Methods Analyses were undertaken with 48 species of Velloziaceae, representing all ten genera, with DNA sequences from the atpB-rbcL spacer, trnL-trnF spacer, trnL intron, trnH-psbA spacer, ITS ribosomal DNA spacers and morphology. Key Results Four groups consistently emerge from the analyses. Persistent leaves, two phloem strands, stem cortex divided in three regions and violet tepals support Acanthochlamys as sister to Velloziaceae s. s., which are supported mainly by leaves with marginal bundles, transfusion tracheids and inflorescence without axis. Within Velloziaceae s. s., an African Xerophyta + Talbotia clade is uniquely supported by basal loculicidal capsules; an American clade, Barbacenia s. l. + Barbaceniopsis + Nanuza + Vellozia, is supported by only homoplastic characters. Barbacenia s. l. (Aylthonia + Barbacenia + Burlemarxia + Pleurostima) is supported by a double sheath in leaf vascular bundles and a corona; Barbaceniopsis + Nanuza + Vellozia is not supported by an unambiguous character, but Barbaceniopsis is supported by five characters, including diclinous flowers, Nanuza + Vellozia is supported mainly by horizontal stigma lobes and stem inner cortex cells with secondary walls, and Vellozia alone is supported mainly by pollen in tetrads. Conclusions The results imply recognition of five genera (Acanthochlamys (Xerophyta (Barbacenia (Barbaceniopsis, Vellozia)))), solving the long-standing controversies among recent classifications of the family. They also suggest a Gondwanan origin for Velloziaceae, with a vicariant pattern of distribution.

Apocynaceae sensun strictum from the Mucuge Municipal Park, Bahia, Brazil, including the valid publication of two names in Mandevilla Lindl.

Apocynaceae sensun strictum from the Mucuge Municipal Park, Bahia, Brazil, including the valid publication of two names in Mandevilla Lindl. The flora of Rauvolfioideae and Apocynoideae, which together form Apocynaceae s.s., from the Mucuge Municipal Park, Chapada Diamantina, State of Bahia, Brazil, is presented. Eight species and five genera were recognized. Mandevilla is the most diverse genus, With four species: M. scabra (Hoffmans. ex Roem. & Schult.) K. Schum., M. tenuifolia (J.C. Mikan) Woodson, M. bahiensis (Woodson) M.F. Sales & Kinoshita-Gouvea, and M.microphylla (Stadelm.) M.F. Sales & Kinoshita-Gouvea, the last two are a new status and a new combination, respectively, whose names are being validly published here. The four remaining genera are each represented by one species: Couma rigida Mull. Arg., Stipecoma peltigera (Stadelm.) Mull Arg,, Temnadenia violacea (Veil.) Miers, and Himatanthus bracteatus (A. DC.) Woodson. Identification key, descriptions, comments and illustrations are presented for every species.

Nectandra Rol. ex Rottb. (Lauraceae) in Mato Grosso do Sul State, Brazil

(Nectandra Rol. ex Rottb. (Lauraceae) in Mato Grosso do Sul State, Brazil). This paper presents the taxonomic study of the species of Nectandra from Mato Grosso do Sul. Eight species of Nectandra were identified through the morphological analyses of specimens collected in different regions from the State: N. amazonum Nees, N. cissiflora Nees, N. cuspidata Nees, N. falcifolia (Nees) J.A. Castigl. ex Mart. Crov. & Piccinini, N. gardneri Meisn., N. hihua (Ruiz & Pav.) Rohwer, N. megapotamica (Spreng.) Mez and N. psammophila Nees. Identification key, morphological descriptions, geographic distribution, habitat, fenologic aspect, taxonomic comments, and illustrations are presented.

Neotypifications of Linnaean names in Hybanthus (Violaceae)

Current studies in South American Violaceae detected the necessity of neotypes for Viola calceolaria L. (equivalent to Hybanthus calceolaria (L.) Oken) and Viola oppositifolia L. (equivalent to Hvbanthus oppositifolius (L.) Taub.), names of species originally described in Loefling`s her Hispanicum, but without validly published names.

A new species of the genus Mezilaurus Taubert (Lauraceae) for the Brazilian flora

(A new species of the genus Mezilaurus Taubert (Lauraceae) for the brazilian flora). The species was named Mezilaurus vanderwerffii F. M. Alves & J.B. Baitello and is characterized by leaves with dense, glandular dots on the adaxial surface. The species is reported for Cerrado, Cerradao, and Semideciduous Forest surrounding the Pantanal Matogrossense

A new species of Vriesea Lindl. (Bromeliaceae, Tillandsioideae) from Serra da Canastra, Minas Gerais State, Brazil

A new species of Vriesea Lindl. belonging to section Xiphion (E. Morren) E. Morren ex Mez. - V. sanfranciscana Versieux & Wand.- is described and illustrated. The species is only known to occur in the Serra da Canastra National Park, located in the southwestern Minas Gerais, Brazil, and is morphologically related to V. atropurpurea Silveira from serra do Cipo, Espinhaco range.