Eric de Camargo Smidt

Demography, and genetic and morphological variability of the endangered Sophronitis sincorana (Orchidaceae) in the Chapada Diamantina, Brazil

We carried out a demographic study and evaluated the genetic and morphological variability in five populations of the endangered Sophronitis sincorana (Orchidaceae) endemic to Northeastern Brazil, based on allozyme and morphometric analyses. Plant density was approximately 0.5 plants/m2, and the projected total number of plants was approximately 50,000 individuals. However, fruit set and recruitment of individuals are rare. The genetic variability was very high in all populations (P = 100, A = 3.0−3.5, He = 0.33−0.48), and all populations presented similar values of morphological variability. Low genetic and morphological structuring were found in the species (FST = 0.053, AMRPP = 0.018). The elevated coefficient of endogamy encountered in populations of S. sincorana indicates the occurrence of structuring within the populations. The lack of correlation between morphological and genetic variation in this species indicates that none of the markers examined should be used separately for either conservation purposes.

ITS and trnH-psbA as Efficient DNA Barcodes to Identify Threatened Commercial Woody Angiosperms from Southern Brazilian Atlantic Rainforests

The Araucaria Forests in southern Brazil are part of the Atlantic Rainforest, a key hotspot for global biodiversity. This habitat has experienced extensive losses of vegetation cover due to commercial logging and the intense use of wood resources for construction and furniture manufacturing. The absence of precise taxonomic tools for identifying Araucaria Forest tree species motivated us to test the ability of DNA barcoding to distinguish species exploited for wood resources and its suitability for use as an alternative testing technique for the inspection of illegal timber shipments. We tested three cpDNA regions (matK, trnH-psbA, and rbcL) and nrITS according to criteria determined by The Consortium for the Barcode of Life (CBOL). The efficiency of each marker and selected marker combinations were evaluated for 30 commercially valuable woody species in multiple populations, with a special focus on Lauraceae species. Inter- and intraspecific distances, species discrimination rates, and ability to recover species-specific clusters were evaluated. Among the regions and different combinations, ITS was the most efficient for identifying species based on the ‘best close match’ test; similarly, the trnH-psbA + ITS combination also demonstrated satisfactory results. When combining trnH-psbA + ITS, Maximum Likelihood analysis demonstrated a more resolved topology for internal branches, with 91% of species-specific clusters. DNA barcoding was found to be a practical and rapid method for identifying major threatened woody angiosperms from Araucaria Forests such as Lauraceae species, presenting a high confidence for recognizing members of Ocotea. These molecular tools can assist in screening those botanical families that are most targeted by the timber industry in southern Brazil and detecting certain species protected by Brazilian legislation and could be a useful tool for monitoring wood exploitation.

Thismia prataensis (Thismiaceae), a New Species from the Brazilian Atlantic Rain Forest

Abstract A new Thismiaceae species, Thismia prataensis , from the Brazilian Atlantic Rain Forest is described and illustrated. This species was found growing in the “Serra da Prata” mountain range, Morretes, Paraná State, southeastern Brazil, and is distinguished from the other species in the genus by the presence of six bracts in two whorls, free interstaminal lobes, six depressions that surround the throat, double longitudinal lamellae on the outside of the floral tube and stigma with papillose surface. This is the most southerly record for the group in the Neotropical region. A key of the Thismia species inhabiting the Atlantic Rain Forest is also provided.

Spiral root hairs in Spiranthinae (Cranichideae: Orchidaceae)

Abstract(Spiral Root Hairs in Spiranthinae (Cranichideae: Orchidaceae) Root hairs are extensions of root epidermal cells, usually unicellular and unbranched. Root hairs studies usually focus on the relevant physiological and molecular aspects and have become a well-studied model of cellular differentiation and growth. In the Orchidaceae structures such as velamen, as well as exodermal and endodermal thickening, have been considered taxonomically valuable for categorizing different groups. While velamen has been greatly studied and discussed, root hairs are rarely mentioned in the literature or are merely characterized as simple root hairs. In the present study, we characterize morphologically spiral root hairs in a broad sample species of Spiranthinae. We analyzed roots from 23 species included in 12 genera from the subtribe Spiranthinae and Prescottia stachyodes (Sw.) Lindl. (Cranichidinae) as an external group, using light microscopy and scanning electron microscopy. Spiral root hairs are a continuation of the velamen and are found among simple root hairs; they differ from the latter in the type of wall rupture displayed. Spiral root hairs occur frequently among the species we analyzed, in both epiphytic as well as terrestrial species. We believe these root hairs help increase the opening (facilitating the entrance of colonizers), improve fluid absorption, and increase adherence to the substrate. The presence of spiral root hairs may also carry taxonomic importance in studies with a broader sample of Orchidoideae.

Multiple Geographical Origins of Environmental Sex Determination enhanced the diversification of Darwin’s Favourite Orchids

Environmental sex determination (ESD) − a change in sexual function during an individual life span driven by environmental cues − is an exceedingly rare sexual system among angiosperms. Because ESD can directly affect reproduction success, it could influence diversification rate as compared with lineages that have alternative reproductive systems. Here we test this hypothesis using a solid phylogenetic framework of Neotropical Catasetinae, the angiosperm lineage richest in taxa with ESD. We assess whether gains of ESD are associated with higher diversification rates compared to lineages with alternative systems while considering additional traits known to positively affect diversification rates in orchids. We found that ESD has evolved asynchronously three times during the last ~5 Myr. Lineages with ESD have consistently higher diversification rates than related lineages with other sexual systems. Habitat fragmentation due to mega-wetlands extinction, and climate instability are suggested as the driving forces for ESD evolution.

Revisão taxonômica de Acianthera sect. Pleurobotryae (Orchidaceae, Pleurothallidinae)

Acianthera Scheidew. comprises about 200 species with Neotropical distribution; in the most recent proposal of taxonomic synopsis for the genus, Chiron & van den Berg created 10 sections, among which Acianthera sect. Pleurobotryae, subject of this study. The section Pleurobotryae can be distinguished from other Acianthera sections by the long unguiculate lip with a mobile articulation, and the cylindrical to laterally flattened leaves, attached to a thread like cauloma. Their specimens are rather distributed in Southern and Southeastern Brazil and Northeastern Argentina. In this work a taxonomic study of the section Pleurobotryae is presented. Three new synonyms and a new combination are proposed for the group. Of the six species previously assigned to this section, only four are accepted here: Acianthera atropurpurea (Barb.Rodr.) Chiron & van den Berg, A. crepiniana (Cogn.) Chiron & van den Berg, A. hatschbachii (Schltr.) Chiron & van den Berg, and A. mantiquyrana (Barb.Rodr.) V.T. Rodrigues & F. Barros.

O gênero Phymatidium (Orchidaceae: Oncidiinae) no estado do Paraná

Resumo A partir de consultas a herbarios nacionais e estrangeiros, cinco especies e duas variedades de Phymatidium Lindl. foram encontradas no Parana: Phymatidium aquinoi , P. delicatulum , P. delicatulum var. curvisepalum , P. falcifolium , P. hysteranthum , P. microphyllum e P. microphyllum var. herteri . O genero e registrado em 35 dos 399 municipios paranaenses, principalmente na Floresta Ombrofila Densa e Floresta Ombrofila Mista, localizadas na Serra do Mar, Primeiro e Segundo Planaltos. Segundo os criterios da IUCN, a maioria dos taxons encontra-se classificada na categoria vulneravel para o estado. Phymatidium delicatulum e a especie mais comum, com ampla distribuicao, e P. hysteranthum a especie mais restrita, registrada pela primeira vez no estado. Chave de identificacao dos taxons, descricoes, ilustracoes, dados sobre distribuicao geografica e conservacao, alem de uma lista de materiais representativos, sao apresentados. The genus Phymatidium (Orchidaceae: Oncidiinae) in the state of Parana Abstract Based on the study of material in Brazilian and foreign herbaria, five species and two varieties of Phymatidium are recognized for Parana state: Phymatidium aquinoi , P. delicatulum , P. delicatulum var. curvisepalum , P. falcifolium , P. hysteranthum , P. microphyllum and P. microphyllum var. herteri . The genus is recorded in 35 of the 399 municipalities of the state, mostly inhabiting Floresta Ombrofila Densa and Floresta Ombrofila Mista vegetation, situated in the Serra do Mar, Primeiro and Segundo Planaltos. Following IUCN criteria, most taxa are classified here as vulnerable in the state. Phymatidium delicatulum is the commonest species, with the widest distribution, and P. hysteranthum , with the narrowest distribution, is recorded for the first time in Parana. An identification key for species and varieties, descriptions, illustrations, data on distribution and conservation, and a list of representative material are provided herewith.

Leaf anatomical and molecular studies in Bulbophyllum section Micranthae (Orchidaceae) and their implications for systematics

Bulbophyllum section Micranthae comprises 12 species of rupicolous or epiphytic orchids occurring in forests or in open rocky fields in Cerrado/Atlantic Forest ecotones throughout South America. We examined the leaf anatomy of 14 species and compared them with molecular data (nrITS) in phylogenetic analyses. The leaves of Bulbophyllum section Micranthae are characterised by uniseriate epidermis, with periclinal external cell wall thicker than the internal, presence of epicuticular wax, stomata present only on the abaxial surface with suprastomatic chambers, and collateral vascular bundles associated with sclerenchyma fibres. Some of these characters are shared with other rupicolous Orchidaceae species, demonstrating adaptive convergence in xeromorphic habitats. We found some anatomical characteristics with phylogenetic value. Bulbophyllum section Micranthae can be separated into two lineages: those with needle-like leaves, or flat leaves. The analyses show that anatomical characters as well as molecular data may contribute to the development of phylogenetic hypotheses.

From tree tops to the ground: Reversals to terrestrial habit in Galeandra orchids (Epidendroideae: Catasetinae)

The colonization of the epiphytic niche of Neotropical forest canopies played an important role in orchids extraordinary diversification, with rare reversions to the terrestrial habit. To understand the evolutionary context of those reversals, we investigated the diversification of Galeandra, a Neotropical orchid genus which includes epiphytic and terrestrial species. We hypothesized that reversion to the terrestrial habit accompanied the expansion of savannas. To test this hypothesis we generated a comprehensive time-calibrated phylogeny and employed comparative methods. We found that Galeandra originated towards the end of the Miocene in Amazonia. The terrestrial clade originated synchronously with the rise of dry vegetation biomes in the last 5 million years, suggesting that aridification dramatically impacted plant diversification and habits in the Neotropics. Shifts in habit impacted floral spur lengths and geographic range size, but not climatic niche. The longer spurs and narrower ranges characterize epiphytic species, which probably adapted to specialized long-tongued Euglossini bee pollinators inhabiting forested habits. The terrestrial species present variable floral spurs and wider distribution ranges, with evidence of self-pollination, suggesting the loss of specialized pollination system and concomitant range expansion. Our study highlights how climate change impacted habit evolution and associated traits such as mutualistic interactions with pollinators.

Sarcoglottis catharinensis (Orchidaceae): a new species from Brazilian Atlantic Forest

SummaryA new species, Sarcoglottis catharinensis Mancinelli & E. C. Smidt, found in the Atlantic Forest of Brazil, is described and illustrated. The species was collected in Serra Quiriri, Garuva municipality, Santa Catarina State and grows in montane forest on turfy soil. It is differentiated from the remaining Sarcoglottis C. Presl species by the truncate and rostrate apex of the lip.