VEGETAÇÃO E FLORA NO CARIRI PARAIBANO

A study of the flora and vegetation of the Cariri Region of Paraíba was carried out in order to support strategies for conservation and sustainable use of the region's caatinga. For the floristic survey, the whole Cariri region was considered, but for the study of vegetation structure, two areas in different states of preservation were chosen: a well-preserved site, the Fazenda Almas private reserve (RPPN; 7°2815”S, 36°53'51”W), and a significantly altered site, the São João do Cariri Experimental Station (7º23'48”S and 36º31'55”W). In the floristic survey 396 species were observed, with the family Leguminosae being the most diverse. In São João do Cariri, 26 species of trees or shrubs were observed with the dominants being Caesalpinia pyramidalis, Croton sonderianus, Combretum leprosum and Jatropha mollissima. In Fazenda Almas, 67 species of trees or shrubs were found, with the most prominent being Croton sonderianus, Caesalpinia pyramidalis, and also Manihot catingae. The low diversity found at the São João de Caririri site was reflected in all the structural parameters of the vegetation, indicating a degradation of the local vegetation which has been used for years for grazing goats. The species diversity in the Fazenda Almas RPPN was much higher than that observed in São João do Cariri or other areas of caatinga in Paraíba.Realizou-se um estudo da flora e da estrutura da vegetação no Cariri Paraibano com o objetivo de subsidiar estratégias para conservação e uso sustentável da caatinga na região. No levantamento florístico considerouse toda a área do Cariri, mas para os estudos de estrutura foram selecionadas duas localidades em diferentes estádios de conservação: a RPPN Fazenda Almas (7°2815”S, 36°53'51”W), Cariri Ocidental, área mais preservada, e a Estação Experimental de São João do Cariri (7º23'48”S e 36º31'55”W), Cariri Oriental, com vegetação bastante alterada. No levantamento florístico foram observadas 396 espécies, sendo a família Leguminosae a mais diversa. Em São João do Cariri foram observadas 26 espécies arbóreo-arbustivas e a dominância de Caesalpinia pyramidalis, Croton sonderianus, Combretum leprosum e Jatropha mollissima. Na Fazenda Almas registraram-se 67 espécies arbóreo-arbustivas, destacando-se também Croton sonderianus e Caesalpinia pyramidalis e ainda Manihot catingae. A baixa diversidade florística encontrada na EE São João do Cariri refletiu-se em todos os parâmetros estruturais de vegetação analisados indicando a degradação da vegetação local, que há anos é utilizada para pastoreio de caprinos. A diversidade na RPPN Fazenda Almas foi bastante superior à observada em São João do Cariri e em outras áreas de caatinga na Paraíba

A new classification of Cyperaceae (Poales) supported by phylogenomic data

Cyperaceae (sedges) are the third largest monocot family and are of considerable economic and ecological importance. Sedges represent an ideal model family to study evolutionary biology because of their species richness, global distribution, large discrepancies in lineage diversity, broad range of ecological preferences, and adaptations including multiple origins of C4 photosynthesis and holocentric chromosomes. Goetghebeur’s seminal work on Cyperaceae published in 1998 provided the most recent complete classification at tribal and generic level, based on a morphological study of Cyperaceae inflorescence, spikelet, flower and embryo characters plus anatomical and other information. Since then, several family‐level molecular phylogenetic studies using Sanger sequence data have been published. Here, more than 20 years after the last comprehensive classification of the family, we present the first family‐wide phylogenomic study of Cyperaceae based on targeted sequencing using the Angiosperms353 probe kit sampling 311 accessions. Additionally, 62 accessions available from GenBank were mined for overlapping reads and included in the phylogenomic analyses. Informed by this backbone phylogeny, a new classification for the family at the tribal, subtribal and generic levels is proposed. The majority of previously recognized suprageneric groups are supported, and for the first time we establish support for tribe Cryptangieae as a clade including the genus Koyamaea. We provide a taxonomic treatment including identification keys and diagnoses for the 2 subfamilies, 24 tribes and 10 subtribes and basic information on the 95 genera. The classification includes five new subtribes in tribe Schoeneae: Anthelepidinae, Caustiinae, Gymnoschoeninae, Lepidospermatinae and Oreobolinae. This article is protected by copyright. All rights reserved

Biodiversity recovery of Neotropical secondary forests

Old-growth tropical forests harbor an immense diversity of tree species but are rapidly being cleared, while secondary forests that regrow on abandoned agricultural lands increase in extent. We assess how tree species richness and composition recover during secondary succession across gradients in environmental conditions and anthropogenic disturbance in an unprecedented multisite analysis for the Neotropics. Secondary forests recover remarkably fast in species richness but slowly in species composition. Secondary forests take a median time of five decades to recover the species richness of old-growth forest (80% recovery after 20 years) based on rarefaction analysis. Full recovery of species composition takes centuries (only 34% recovery after 20 years). A dual strategy that maintains both old-growth forests and species-rich secondary forests is therefore crucial for biodiversity conservation in human-modified tropical landscapes. Copyright © 2019 The Authors, some rights reserved

The Systematics of Rhynchospora Section Dichromena (Cyperaceae).

The thesis is a revision of Rhynchospora section Dichromena, a neotropical group of sedges comprising twenty-two species and ranging from Virginia to Argentina. In addition to the traditional taxonomic approach, information from anatomy, morphology, cytology, ecology, and pollination biology was used. Keys, descriptions, synonymy, and cladistic analyses are presented. Two new species and one new subspecies are described. Many of the poorly known species are illustrated for the first time. The only previous study of all of section Dichromena was included in Kukenthal's (1938-52) monograph of the Rhynchosporoideae. The importance of his contribution to the underst and ing of Dichromena was limited by the small number of specimens available to him. Of the twenty-seven taxa of specific rank or below in Kukenthal's monograph, only eleven are retained unchanged. Dichromena is not distinct enough to be maintained as a separate genus. Within section Dichromena, one of the most conspicuous features of many species is white bracts. These evolved three times: anatomical evidence indicates that in one group the white appearance is due to a loss of chlorenchyma while in another it is due to an added layer of small, light refracting parenchyma cells and in the third it is due to the enlargement of the epidermal cells. Field observations in six countries in North and South America show that at least seven species, including five green-bracted species, are visited and probably pollinated by various insects, primarily species of Hymenoptera (Apoidea). The hymenopteran visitors, mostly females collecting pollen, visit the flowers only in mid-morning when the athers and stigmas have emerged from the spikelet; they show pollinator constancy. Examination of the body surfaces of the insects by SEM reveals the presence of pollen of Rhynchospora section Dichromena.Ph.D.BotanyUniversity of Michiganhttp://deepblue.lib.umich.edu/bitstream/2027.42/158926/1/8215096.pd

Byrsonima crassifolia

Angiosperm

Smilax laurifolia

Angiosperm

Smilax laurifolia

Angiosperm