Abstract Leafcutter ants are among the most important agricultural and forest pests in the Neotropical region, given that they use plant matter as substrate for the growth of their mutualist fungus Leucoagaricus gongylophorus. Plant-based insecticides and fungicides have shown potential for controlling these ants. The present study assessed the hydroalcoholic extract activity of four fern fronds (dry and rainy periods) on the mutualist fungus of leafcutter ants. Fungal mycelium suspensions were seeded on the surface of tubes containing fern extracts at a concentration of 5 mg/mL and 100 μg/mL. The chemical profile of the extracts was analyzed by thin layer chromatography (TLC). Extracts (dry period) at a concentration of 5 mg/mL inhibited the growth of the fungus: Macrothelypteris torresiana and Dicksonia sellowiana (less than 20%), Niphidium crassifolium (approximately 40%), Parapolystichum effusum extract (100%). None of the extracts (dry and rainy periods) inhibited fungal growth at a concentration of 100 μg/mL. The chemical profile analysis of the extracts indicated the presence of beta-sitosterol, friedelinol, rutin, and kaempferol. The crude extracts of P. effusum and N. crassifolium were the most promising in future formulations of antifungal products. Thus, ferns are potential plants in the search for environmentally-friendly substances for sustainable agriculture. region gongylophorus Plantbased Plant based dry periods mgmL mg mL 10 μgmL μg μg/mL TLC. TLC . (TLC) period less 20%, 20 20% , 20%) approximately 40%, 40 40% 40%) 100%. 100% (100%) betasitosterol, betasitosterol beta sitosterol, sitosterol beta-sitosterol friedelinol rutin kaempferol P N products Thus environmentallyfriendly environmentally friendly agriculture 1 (TLC 2 4 (100% (100 (10 (1 (

Resumo Formigas cortadeiras estão entre as pragas agrícola e florestal mais importante da região Neotropical, uma vez que utilizam material vegetal como substrato para crescimento de seu fungo mutualista Leucoagaricus gongylophorus. Inseticidas e fungicidas de origem vegetal têm mostrado potencial para o controle dessas formigas. O presente estudo avaliou a atividade de extratos hidroalcóolicos de frondes de quatro espécies de samambaias (períodos seco e chuvoso) sobre o fungo mutualista de formigas cortadeiras. Suspensões do micélio fúngico foram semeadas na superfície dos tubos contendo extratos das samambaias na concentração de 5 mg/mL e 100 μg/mL. O perfil químico dos extratos foi analisado por cromatografia em camada delgada (CCD). Extratos (período seco) na concentração de 5 mg/mL inibiram o crescimento do fungo: Macrothelypteris torresiana e Dicksonia sellowiana (menos de 20%) Niphidium crassifolium (aproximadamente 40%), Parapolystichum effusum (100%). Os extratos (períodos seco e chuvoso) na concentração 100 μg/mL não promoveram inibição. A análise do perfil químico dos extratos das quatro espécies indicou a presença de beta-sitosterol, friedelinol, rutina e canferol. Os extratos brutos de P. effusum e N. crassifolium foram os mais promissores para futuras formulações de produtos antifúngicos. Assim sendo, as samambaias são plantas potenciais na busca de substâncias com menor impacto ambiental para uma agricultural sustentável. Neotropical gongylophorus períodos chuvoso mgmL mg mL 10 μgmL μg CCD. CCD . (CCD) período menos 20% 20 aproximadamente 40%, 40 40% , 40%) 100%. 100% (100%) inibição betasitosterol, betasitosterol beta sitosterol, sitosterol beta-sitosterol friedelinol canferol P N antifúngicos sendo sustentável 1 (CCD 2 4 (100% (100 (10 (1 (

Abstract Microgramma vacciniifolia, an epiphyte fern, hosts of two stem galls. One is induced by Tortrimosaica polypodivora (Lepidoptera), which can also induce galls in M. squamulosa and M. mortoniana. The alterations induced by T. polypodivora on M. vacciniifolia stem were compared to non-galled organs to evaluate the anatomical potentials of host ferns in response to a galling Lepidoptera. Histochemical and histometrical comparisons between galled and non-galled stems were performed to assess the processes leading to gall formation. M. vacciinifolia and M. squamulosa galls were anatomically similar, although their sizes differ, reflecting the growth potential of each host species. Simple structural alterations, such as hyperplasia of cortical and pericycle cells, occur during gall formation, while cell hypertrophy, common in more complex galls, was only detected on the pericycle. Meristele size remained unaltered in galls, but the pericycle appeared hyperplasic. The protective scales were broader in galls. A nutritive tissue with lipids, typical to Lepidoptera galls, was observed around the larval chamber, with small cells and meristematic activity. Starch, proteins, and reducing sugars accumulated in nutritive cells are uncommonly found in Lepidoptera galls. Despite simple structural alterations, T. polypodivora induced a gradient of primary metabolites, similar to angiosperm galls. fern Lepidoptera, , (Lepidoptera) M mortoniana T nongalled non formation differ species hypertrophy hyperplasic lipids chamber activity Starch proteins metabolites (Lepidoptera

Resumo Microgramma vacciniifolia, uma samambaia epifíta, abriga duas galhas caulinares, uma delas induzida por Tortrimosaica polypodivora (Lepidoptera), que também induz galhas em M. squamulosa e em M. mortoniana. Alterações induzidas por T. polypodivora nos caules de M. vacciniifolia foram comparadas aos caules não-galhados, para avaliar os potenciais anatômicos das samambaias hospedeiras em resposta a um Lepidoptera galhador. Comparações histoquímicas e histométricas foram realizadas para avaliar os processos que levam à formação das galhas. As galhas de M. vacciinifolia e M. squamulosa são anatomicamente semelhantes, embora seus tamanhos diferem, refletindo o potencial de crescimento de cada espécie hospedeira. Alterações estruturais simples ocorrem durante a formação da galha, como hiperplasia das células corticais e pericíclicas, enquanto hipertrofia celular, comum em galhas mais complexas, é detectada apenas no periciclo. Os meristelos não têm o tamanho alterado, mas o periciclo apresenta hiperplasia. As escamas são mais largas nas galhas. Ao redor da câmara larval observa-se um tecido nutritivo com lipídios, típico das galhas de Lepidoptera, com células pequenas e atividade meristemática. Amido, proteínas e açúcares redutores também se acumulam nas células nutritivas, raramente relatado em galhas de Lepidoptera. Apesar das alterações estruturais simples, T. polypodivora induz o estabelecimento de um gradiente de metabólitos primários, semelhante ao observado em galhas de angiospermas. epifíta caulinares , (Lepidoptera) M mortoniana T nãogalhados, nãogalhados galhados, galhados não-galhados galhador semelhantes diferem hospedeira galha pericíclicas celular complexas alterado observase observa lipídios meristemática Amido nutritivas primários angiospermas (Lepidoptera

ABSTRACT Acrostichum danaeifolium, a Neotropical fern, occurs preferentially in marshy areas or at the margins of lakes and mangroves. Microlepidoptera larvae burrow through the petioles of the fern, preferentially on the non-expanded leaves. The galleries in the petiole create a new microhabitat, harboring a rich fauna of arthropods. The aim of the present study was to assess the richness of ants associated with its petiole. The study was conducted in a population of A. danaefolium from the Atlantic Forest in Rio de Janeiro state, Southeastern Brazil. Six collections were carried out every two months (2009-2010), three in the dry and three in the rainy season. The leaves were divided into three development stages: non-expanded leaves (NEL), expanded leaves (EL) and senescent leaves (SL). Seven leaves from each phase were randomly collected from seven individuals. A total of fifteen ant species were recorded. The species with the highest frequency and density in fern petioles were Camponotus crassus and Crematogaster curvispinosa. The highest ant richness and abundance was found in senescent leaves. The high number of ants found in the petioles of Acrostichum danaefolium qualifies it as a potential key species in the marshes and flooded areas where it occurs.

Abstract: Pteridium is a cosmopolitan genus of ferns that possess nectaries on its fronds (fern leaves), thereby attracting ants. Foliar (or extrafloral) nectaries are nectar-producing glands that are not related to pollination, but rather attract ants and other arthropods. Foliar nectaries are found in 101 fern species, belonging to 11 genera and six families. The aim of the study is to characterize the community of ants that visit the fronds of Pteridium esculentum subsp. arachnoideum, as well as daily and seasonal ant abundance in different frond development stages. The study was conducted in the Atlantic Forest of Rio de Janeiro state, Brazil. Bimonthly collections were established, where 30 expanding fronds and 30 fully expanded fronds were randomly marked. In each 1-hour shift starting at 8:30 am and ending at 5:30 pm, the fronds were observed for the presence of ants. Thirty three ant species were recorded on the Pteridium esculentum subsp. arachnoideum fronds, distributed into six subfamilies and 13 genera. The most abundant species were Solenopsis sp.1 and Ectatomma tuberculatum. Eight ant species were observed foraging the nectaries of tropical bracken fern fronds. Ectatomma tuberculatum has been observed feeding on the nectaries and patrolling the fronds. Ant activity peak was on mid-day during the rainy season. The tropical bracken fern Pteridium esculentum subsp. arachnoideum has a rich (the highest recorded until now on Pteridium species) and diverse ant community on its fronds, mainly on the expanding fronds. The presence of generalist predatory ants (Ectatomma tuberculatum and Solenopsis sp.1) during the entire study period suggests a positive interaction between ants and Pteridium esculentum subsp. arachnoideum. Abstract leaves, leaves , leaves) or extrafloral nectarproducing nectar producing pollination arthropods 10 1 families subsp stages state Brazil established 3 marked 1hour hour 830 8 8:3 530 5 5:3 pm sp1 sp sp. midday mid day season 83 8: 53 5:

Resumo: Pteridium é um gênero cosmopolita de samambaias que possui nectários em suas frondes (folhas de samambaias), atraindo formigas. Nectários foliares (ou extraflorais) são glândulas produtoras de néctar que não estão relacionadas com a polinização, mas podem atrair formigas e outros artrópodes. Nectários foliares já foram registrados em 101 espécies de samambaias, pertencentes a 11 gêneros e seis famílias. O objetivo do estudo é caracterizar a comunidade de formigas que visitam as frondes de Pteridium esculentum subsp. arachnoideum, bem como a abundância diária e sazonal das formigas em diferentes estágios foliares. O estudo foi realizado na Mata Atlântica do estado do Rio de Janeiro, Brasil. Foram estabelecidas coletas bimestrais, onde foram marcadas aleatoriamente 30 frondes em expansão e 30 frondes totalmente expandidas. Em cada turno de 1 hora com início às 8h30 e término às 17h30, as frondes marcadas foram observadas quanto à presença de formigas. Trinta e três espécies de formigas foram registradas nas frondes do Pteridium esculentum subsp. arachnoideum, distribuídas em seis subfamílias e 13 gêneros. As espécies mais abundantes foram Solenopsis sp.1 e Ectatomma tuberculatum. Foram registradas oito espécies de formigas forrageando os nectários foliares da samambaia. Ectatomma tuberculatum foi observada se alimentando nos nectários e patrulhando as frondes. As formigas tiveram o pico de atividade ao meio-dia e na estação chuvosa. A samambaia tropical Pteridium esculentum subsp. arachnoideum tem uma elevada riqueza (a maior já registrada até o momento para espécies de Pteridium) e diversidade de formigas em suas frondes, com maior frequência nas frondes não totalmente expandidas. A presença de formigas predadoras generalistas (Ectatomma tuberculatum e Solenopsis sp.1) durante todo o período de estudo sugere uma interação positiva entre as formigas e Pteridium esculentum subsp. arachnoideum. Resumo folhas , samambaias) ou extraflorais polinização artrópodes 10 famílias subsp Janeiro Brasil bimestrais 3 expandidas h 8h3 17h30 sp1 sp sp. meiodia meio dia chuvosa 8h 17h3 17h

ABSTRACT Plants represent a huge source of substances, with pharmacological potential. Brazil has a diversity of agricultural insect pests and an urgent need for safer methods of insect control. Dysdercus peruvianus (Guerin-Meneville, 1831), Pyrrhocoridae, is an economically important species of the Order Hemiptera and a pest of cotton (Gossypium hirsutum L., Malvaceae). Secondary metabolites in stems of Clusia hilariana Schltdl., Clusiaceae, such as terpenes and benzophenones, have been reported to be insecticidal. The present study investigated the effects of semi-purified fractions of hexane crude extracts from male C. hilariana stems on development of D. peruvianus. Biological parameters at different stages of development including body malformations, range of molting period and toxicity were evaluated. Most insects died and failed to develop due to attachment of their exuviae to the abdomen. Deformations of wings and defective tarsi also occurred. The secondary metabolites from semi-purified fractions of C. hilariana caused mortality, interference in molting and metamorphosis, and body deformations, probably by interacting with the neuroendocrine system. The results demonstrate the potential of C. hilariana extracts as an alternative for the control of the phytophagous insect D. peruvianus and for the development of environmentally safe and biodegradable bio insecticides.

Abstract Galls are neoformed plant structures created by cell hyperplasia and hypertrophy induced by a number of organisms, especially insects. After adult insects hatch, senescent galls may remain on the host plant and be occupied by a succession of fauna, the most important and dominant being ants. This study aimed at characterizing the ant fauna successor of stem galls induced by microlepidoptera in Microgramma squamulosa (Kaulf.) de la Sota (Polypodiaceae). Four collections were carried out in the municipality of Nova Friburgo, Rio de Janeiro state, Brazil. The galls were packed in plastic bags and taken to the laboratory. Ants were euthanized and conserved in 70° GL alcohol and later identified. A total of 49 stem galls were collected and analyzed, 15 containing microlepidoptera galler larvae, one a parasitoid wasp and 33 without the microlepidoptera or parasitoid (67%). Twelve of these galls (39%) contained ants. Six ant species were recorded (Camponotus crassus, Crematogaster curvispinosa, Crematogaster sericea, Procryptocerus sampaioi, Tapinoma atriceps, and Wasmannia auropunctata), all native to Brazil. Ant occupation in M. squamulosa seems to be associated with senescent galls due to hatching of the galler insect, which leaves a hole that allows ants to colonize it, in other words, an opportunistic domatia. Senescent galls resulting from the death of galler insects do not seem to facilitate ant occupation.

BACKGROUND This work describes a chemical study of the essential oil from leaves of Xylopia ochrantha, an endemic Annonaceae species from Brazil, and its activity against Biomphalaria species. Considering its poor solubility in aqueous medium, the essential oil was nanoemulsified to evaluate its action on controlling some mollusc species of genus Biomphalaria, snail hosts of Schistosoma mansoni that causes schistosomiasis, which mainly affects tropical and subtropical countries. OBJECTIVES The main aims of this work were to analyse the chemical composition of essential oil from X. ochrantha, and to evaluate the effect of its nanoemulsion on molluscs of genus Biomphalaria and their oviposition. METHODS Chemical analysis was performed by gas chromatography coupled to mass spectrometry. Nanoemulsions were prepared by a low energy method and characterised by particle size and polydispersity index. Biological assays evaluating the mortality of adult species of B. glabrata, B. straminea and B. tenagophila and their ovipositions upon contact with the most stable nanoemulsion during 24 and 48 h were performed. FINDINGS Chemical analysis by mass spectrometry revealed the majority presence of bicyclogermacrene and germacrene D in the essential oil. The formulation with a hydrophilic-lipophilic balance (HLB) of 9.26 was the most suitable for the oil delivery system. This nanoemulsion caused the mortality in B. tenagophila, B. straminea and B. glabarata of different sizes at levels ranging from 50 to 100% in 48 h. Additionally, the formulation could inhibit the development of deposited eggs. CONCLUSION Thus, these results suggest the use of nanoemulsified essential oil from X. ochrantha as a possible alternative in controlling some Biomphalaria species involved in the schistosomiasis cycle.

Resumo Galhas são estruturas vegetais neoformadas induzidas por interações espécie-específicas entre um organismo indutor e uma planta hospedeira. Licófitas e samambaias são duas linhagens de plantas historicamente classificadas juntas como pteridófitas. Diversos autores sugerem que há uma baixa frequência de galhas em licófitas e samambaias, em comparação com as angiospermas. Este trabalho tem como objetivo fornecer um panorama atualizado sobre as galhas em samambaias no Brasil, disponibilizando informações sobre espécies hospedeiras, galhadores e fauna associada. A sinopse foi realizada compilando-se os dados existentes, atualizando os nomes científicos e agregando informações novas obtidas pelos autores em trabalhos de campo. Até o momento, foram registradas galhas em 16 espécies de samambaias e nenhum registro em licófitas. Contudo, em apenas três morfotipos de galhas, de três espécies de samambaias, o indutor foi identificado a nível de espécie, com um indutor duvidoso para Pteridium sp. As galhas são induzidas por ácaros (Eriophyidae) e insetos das ordens: Diptera, Lepidoptera, Thysanoptera, Hemiptera, sendo Cecidomyiidae (Diptera) o galhador mais frequente.

Abstract Galls are neo-formed plant structures induced by species-specific interaction between an inducing organism and a host plant. Lycophytes and ferns are two distinct plant lineages historically lumped together as pteridophytes. A number of authors suggest low gall frequency in lycophytes and ferns, compared to angiosperms. This study aimed at compiling an updated overview of fern galls in Brazil, providing information on hosts, gall-inducing organisms and associated fauna. The synopsis was compiled using existent data and by updating scientific names and gathering new information obtained by the authors in fieldwork. To date, galls have been recorded on 16 fern species but none on lycophytes. However, the inducer was identified at species level in only three gall morphotypes from three fern species, with a doubtful inducer for Pteridium sp. Galls are induced by mites (Eriophyidae) and insects of the orders Diptera, Lepidoptera, Thysanoptera, and Hemiptera, Cecidomyiidae (Diptera) being the most frequent galler insect.

ABSTRACT The effects of the hexanic extracts of the fruits and flowers of Clusia fluminensis Planch. & Triana, Clusiaceae, as well as their main constituents, the triterpene lanosterol and the benzophenone clusianone, were evaluated on hemipterans Dysdercus peruvianus and Oncopeltus fasciatus. The topical treatments of insects with the hexanic extracts significantly affected the survival of O. fasciatus, but not that of D. peruvianus. Concomitantly, extracts delayed the development of both hemipterans. Moreover, isolated lanosterol significantly reduced both the survival and development of O. fasciatus and D. peruvianus, while clusianone only reduce the survival of D. peruvianus and marginally inhibited the development of both insects. The results show the specific activity of lanosterol and clusianone against the two evaluated insect species and indicate the potential of compounds derived from C. fluminensis for the development of specific biopesticides for the control of agricultural pests. Subsequent work will examine the mode of action of lanosterol and clusianone isolates from C. fluminensis.

Studies evaluated the effects of hexanic extracts from the fruits and flowers of Clusia fluminensis and the main component of the flower extract, a purified benzophenone (clusianone), against Aedes aegypti. The treatment of larvae with the crude fruit or flower extracts from C. fluminensis did not affect the survival of Ae. aegypti (50 mg/L), however, the flower extracts significantly delayed development of Ae. aegypti. In contrast, the clusianone (50 mg/L) isolate from the flower extract, representing 54.85% of this sample composition, showed a highly significant inhibition of survival, killing 93.3% of the larvae and completely blocking development of Ae. aegypti. The results showed, for the first time, high activity of clusianone against Ae. aegypti that both killed and inhibited mosquito development. Therefore, clusianone has potential for development as a biopesticide for controlling insect vectors of tropical diseases. Future work will elucidate the mode of action of clusianone isolated from C. fluminensis.

Novo gênero e espécie de Cecidomyiidae (Diptera) associados a Microgramma vacciniifolia (Langsd. & Fisch.) Copel. (Polypodiaceae) do Brasil. Um novo gênero de Cecidomyiidae, Primadiplosis Maia, gen.nov.,e uma nova espécie, P. microgrammae Maia, sp. nov., que induz galhas no caule da samambaia Microgramma vacciniifolia (Langsd. & Fisch.) Copel. (Polypodiaceae) são descritos do Brasil (larva, pupa, macho, fêmea e galha).

A new genus and species of gall midge (Diptera, Cecidomyiidae) associated with Microgramma vacciniifolia (Langsd. & Fisch.) Copel. (Polypodiaceae) from Brazil. A new gall midge genus Primadiplosis Maia, gen. nov. and a new species, P. microgrammae Maia,sp. nov., that induces galls on stems of the fern Microgramma vacciniifolia (Langsd. & Fisch.) Copel. are described from Brazil (larva, pupa, male, female, and gall).

As pteridófitas Anemia tomentosa (Sav.) Sw. var. anthriscifolia (Schrad.) Mickel e Anemia villosa Humb. & Bonpl. ex Willd. estão comumente associadas às "ilhas de vegetação" nos afloramentos rochosos do Rio de Janeiro, sendo ambas tolerantes a dessecação. Este trabalho objetivou analisar a anatomia foliar e identificar estratégias morfológicas que possibilitem o estabelecimento destas espécies num ambiente com restrição hídrica. As pteridófitas foram coletadas na Pedra de Itacoatiara e submetidas às técnicas de estudos anatômicos. Os pecíolos das espécies apresentam epiderme unisseriada com paredes lignificadas, estegmatas cônicos, tricomas tectores unisseriados e glandulares. Em A. villosa foram observados estômatos em protrusão formando linha respiratória. Abaixo da epiderme ocorrem camadas de células com paredes espessas e lignificadas. O parênquima possui compostos fenólicos e grãos de amido. Os feixes vasculares dos pecíolos estão envolvidos por endoderme com estrias de Caspary e o xilema tem forma de "V" (A. villosa) ou forma de arco (A. tomentosa var. anthriscifolia). A lâmina foliar apresenta epiderme uniestratificada com paredes anticlinais sinuosas e periclinais convexas, com estegmatas cônicos e cloroplastos nas faces adaxial e abaxial. As células epidérmicas do bordo foliar são lignificadas em A. villosa. Estômatos na face abaxial com células guarda no mesmo nível ou acima das demais células epidérmicas. Foram observados tricomas tectores multicelulares unisseriados e tricomas glandulares. O mesofilo é dorsiventral, com clorênquima frouxo composto por células braciformes e em forma de "H". Os feixes vasculares são envolvidos por endoderme com estrias de Caspary e possuem extensões de parênquima em direção à epiderme. Os resultados anatômicos foram analisados considerando a interação dessas plantas com fatores abióticos.

The ferns Anemia tomentosa (Sav.) Sw. var. anthriscifolia (Schrad.) Mickel and Anemia villosa Humb. & Bonpl. ex Willd. are widely associated with vegetation islands on rocky outcrops in Rio de Janeiro. Both species are desiccation tolerant. The leaf anatomy of these species was examined aiming to identify morphological characteristics that would allow the establishment of these species in water-scarce environments. The plants were harvested on "Pedra de Itacoatiara" and prepared according to the usual procedures. The petiole has a uniseriate epidermis with lignified cell walls, conical stegmata, and uniseriate multicelular and glandular trichomes. In A. villosa, the stomata protrude in a respiratory line. Under the epidermis the cells have thick, lignified walls. The parenchyma has phenolic compounds and starch grains. The petiole vascular bundles are surrounded by endodermis with Casparian strips and the xylem is V-shaped (A. villosa) or arc-shaped (A. tomentosa var. anthriscifolia). The leaf blades have a uniseriate epidermis with sinuous anticlinal and convex periclinal walls, conical stegmata and chloroplasts on both surfaces. The leaf margins of A. villosa have lignified cells. The guard cells of the stomata on the abaxial surface are on the same level or are raised above ordinary epidermal cells. Multicelular uniseriate trichomes and glandular hairs were observed. The dorsiventral mesophyll has loosely packed chlorenchyma with arm-shaped and H-shaped cells. The vascular bundles are surrounded by endodermis with Casparian strips and with parenchymatic extensions towards the epidermis. Anatomical results were analyzed considering the interaction of these plants with abiotic factors.

O presente trabalho apresenta o levantamento das pteridófitas ocorrentes na Pedra de Itacoatiara, afloramento rochoso localizado no Parque Estadual da Serra da Tiririca, no litoral do Município de Niterói, Estado do Rio de Janeiro, Brasil. Foram registradas 24 espécies pertencentes a 15 gêneros e nove famílias. As famílias encontradas foram Aspleniaceae, Blechnaceae, Dennstaedtiaceae, Lycopodiaceae, Polypodiaceae, Pteridaceae, Schizaeaceae, Selaginellaceae e Thelypteridaceae. Dessas, a mais representativa foi Pteridaceae com oito espécies distribuídas em cinco gêneros (Adiantum, Adiantopsis, Doryopteris, Hemionitis e Pityrogramma). Os gêneros com maior número de espécies foram Anemia (quatro espécies) e Selaginella (três). É apresentada uma chave de identificação e, para cada espécie, são fornecidas informações sobre o padrão de distribuição geográfica, utilidades atribuídas e observações ecológicas. Das 24 espécies encontradas, 13 são úteis ao homem (medicinal, comestível, ornamental, ritualística e cosmética) e duas são tóxicas.

This work presents the inventory of the pteridophytes from Pedra de Itacoatiara. This area is formed by rock outcrop and belongs to Parque Estadual da Serra da Tiririca, on the coast of Niterói, Rio de Janeiro State, Brazil. Twenty four species were registered, belonging to 15 genera and nine families. The families Aspleniaceae, Blechnaceae, Dennstaedtiaceae, Lycopodiaceae, Polypodiaceae, Pteridaceae, Schizaeaceae, Selaginellaceae and Thelypteridaceae were registered in this area. The richest family was Pteridaceae with eight species and five genera (Adiantum, Adiantopsis, Doryopteris, Hemionitis and Pityrogramma). The richest genera were Anemia (four species) and Selaginella (three). A key is provided for species identification. Geographic distribution and attributed usages are also given, as well as comments about ecological features. Thirteen species are useful to men (medicinal, feeding, ornamental, folklore rituals and cosmetic) and two are toxic.

Os glicosídeos cianogênicos são substâncias de defesa encontradas em alguns vegetais, capazes de liberar ácido cianídrico por meio de reações de hidrólise. O presente estudo teve como objetivo avaliar a ocorrência da cianogênese em esporófitos de pteridófitas num afloramento rochoso localizado no Parque Estadual da Serra da Tiririca, Rio de Janeiro, Brasil. Foram analisadas mensalmente durante um ano, folhas férteis, estéreis, jovens (báculos) e caules de 19 espécies de pteridófitas, distribuídas em 13 gêneros e nove famílias. A cianogênese foi caracterizada pelo teste do papel de filtro gotejado com ácido pícrico. Das pteridófitas estudadas, 14 foram pela primeira vez analisadas e 14 espécies apresentaram resultado positivo para a cianogênese. Os resultados encontrados demonstraram haver variação na liberação do ácido cianídrico nas espécies em diferentes partes do vegetal ao longo do período analisado. Microgramma vacciniifolia (Langsd. & Fisch.) Copel. (Polypodiaceae) e Pteridium aquilinum (L.) Kuhn var. arachnoideum (Kaulf.) Brade (Dennstaedtiaceae) mostraram-se cianogênicas durante todo o período analisado.

Cyanogenic glycosides are defense substances found in some plants that are able to produce cyanhydric acid on hydrolysis. The present work aimed to study the occurrence of cyanogenesis in pteridophytes of rocky areas of Pedra de Itacoatiara, State Park of Serra da Tiririca, Rio de Janeiro State. Nineteen species, distributed in 13 genera and nine families have been analyzed monthly, during one year. In each species, the analysis was carried out on fertile leaves, sterile ones, young leaves (croziers) and stems. Cyanogenesis was evidenced using filter paper embedded with picric acid. Among studied species, 14 were analysed here for the first time, and 14 gave a positive picric test. Our results showed variation along time in the production of cyanhydric acid in the vegetal species and parts. The species, Microgramma vacciniifolia (Langsd. & Fisch.) Copel. (Polypodiaceae) and Pteridium aquilinum (L.) Kuhn var. arachnoideum (Kaulf.) Brade (Dennstaedtiaceae) were cyanogenic all along the studied period.