Floristic mosaics of the threatened Brazilian campo rupestre

The increase in rates of habitat loss requires an understanding of how biodiversity is distributed. Campo rupestre is an old, climatically buffered, and infertile landscape located in Brazil. Considered a biodiversity hotspot, the campo rupestre is mainly threatened by mining activity that requires a large operating area. Campo rupestre is known for its restricted distribution area and high abiotic heterogeneity, which modulates species coexistence and richness. To recognise the association between habitat type and plant communities, we propose to describe the floristic composition of herbaceous and shrub components in four habitats of the campo rupestre comprising quartzite and ferruginous substrate. We classified habitat types by the main surface soil features. In each habitat, we sampled ten 100-m2 plots to access information on the shrub and ten 1-m2 plots for the herbaceous component. Altogether we sampled 153 species, belonging to 38 families. The cluster analysis ordered by Sorensen metric indicates a clear distinction of species composition in the shrub component in the four habitats. However, the floristic composition of the herbaceous component was similar between the four habitats but showed a distinction when contrasting with the substrate type. Our results highlight the local taxonomic distinction between habitat types and substrates, indicating that the ecological distinction among substrate types of the campo rupestre cannot be overlooked in conservation and restoration actions.

THE INFLUENCE OF LIGHT QUALITY IN THE in vitro CULTIVATION OF Cattleya crispata

ABSTRACT: Micropropagation technique is a valuable alternative for high quality genetic preservation of endemic species such as the orchid Cattleya crispata from “Campo Rupestre Ferruginoso”. This study aims to evaluate the influence of light quality on in vitro multiplication and elongation phases, offering new insights on the limiting factors of C. crispata. Seeds extracted from capsules were used for inoculation in the culture medium. Four light sources were evaluated for in vitro culture, namely: fluorescent lamp, white LEDs, red LEDs and red/blue LEDs. Data about the number of shoots, shoot length, shooting vigor and pigment content were assessed at 90 days of in vitro culture. Based on the recorded results, white LEDs are the most suitable ones for in vitro multiplication and elongation phases of C. crispata. It offers higher quality for seedling production and increases the chances of genetic conservation of the species. Keywords: ‘Campo Rupestre Ferruginoso’; in vitro propagation; wavelength; LEDs.

ESTIMATIVA DA ÁREA FOLIAR DE Myrcia variabilis Mart. ex DC. (MYRTACEAE)

A espécie Myrcia variabilis (Myrtaceae) é nativa e endêmica do Brasil e pode ser encontrada em ambientes abertos, como o Cerrado, Campo Rupestre e em fragmentos da Mata Atlântica. A planta é conhecida popularmente como “goiabinha-do-campo-roxa” e é utilizada pelas comunidades tradicionais no tratamento de feridas e diarreias. Considerando-se o potencial medicinal da espécie, existe a necessidade de pesquisas básicas envolvendo aspectos relacionados à propagação, crescimento e desenvolvimento, tais como o estudo da área foliar. No entanto, há dificuldade para realizar esta mensuração devido a necessidade da aquisição de equipamentos de valor elevado e técnicas destrutivas. Métodos não destrutivos permitem acompanhar o crescimento da planta e oferecem precisão dos dados, preservando a integridade. O objetivo desse estudo foi estimar a área foliar de M. variabilis e estabelecer modelos matemáticos utilizando os parâmetros lineares dimensionais comprimento e largura. Foram coletadas 200 folhas de 10 espécimes de uma população de M. variabilis presentes em uma área de cerrado alterado, no Município de Lavras – MG. Após a coleta, as folhas foram escaneadas e analisadas para determinação das medidas lineares. Foi observado que o produto das medidas lineares comprimento e largura são suficientes para estimar a área foliar da espécie. O presente estudo contribui para o estudo da espécie M. variabilis, por eliminar os métodos destrutivos para estimar a área foliar. Além disso, o modelo linear demonstrou bom ajuste, sendo a ferramenta ideal para estimar a área foliar desta espécie, principalmente em estudos que investiguem o seu crescimento e desenvolvimento.

Rediscovery of Oocephalus foliosus (Hyptidinae—Lamiaceae): notes on taxonomy and conservation of a species endemic to the campo rupestre of Central Brazil

Oocephalus foliosus was described in the first half of 19th century, based on a collection from central Goiás state, Brazil, being collected again only three times in surrounding areas. Although this species seems to be rare and endemic to a narrow area, it has never been listed on any threatened list or had its conservation status assessed. Recently, we recorded a small population of O. foliosus in the Pireneus peak, an area of campo rupestre located in the municipality of Pirenópolis, Goiás, allowing us to improve the species description, assess its extinction risk and comment on its taxonomy. Also, a second step lectotypification was needed to the species and is here proposed.

Spatiotemporal Distribution of Herbivorous Insects Along Always-Green Mountaintop Forest Islands

Insects make up the bulk of terrestrial diversity and about half of insect species are herbivores that have direct relationships with their host plants and are the basis of the entire food chain, on which wildlife and humanity depend. Some herbivorous insect traits, such as their spatio-temporal distribution, are especially relevant in the current scenario of global changes, which are more pronounced in high elevation areas, helping to improve the effectiveness of conservation actions. Here we evaluated the influence that different spatiotemporal scales have on three free-feeding herbivorous insect guilds (fluid-feeding, leaf-chewing, and xylophagous insects) in montane forest islands immersed in a grassland-dominated matrix (campo rupestre). We assessed whether species turnover or nestedness was the main component determining both spatial and temporal species composition variation (β-diversity) of the herbivorous insect community. We also checked the temporal effect on herbivorous insect guilds composition between vertical strata. We sampled herbivorous insects during two summers and two winters in 14 forest islands of different sizes and shapes in a natural mountainous fragment located in southeastern Brazil. A total of 6597 herbivorous insects representing 557 morphospecies were sampled, 290 of which were fluid-feeding, 147 leaf-chewing and 120 xylophagous insects. We found a main contribution of time scale in the organization of the herbivorous insect composition sampled in this study, mainly by turnover, with small differences among guilds. Additionally, we could see that climate determined the local variation of species, corroborating that we have a highly variable always-green system over space and time where the understory community varies less in comparison to the canopy community. Our findings suggest that long-term ecological research on herbivorous community structure in relation to climatic variation is a key element for future investigations, which can be decisive for the conservation of herbivorous insect communities. We also suggest that the effects of anthropogenic pressures must be monitored in this system, since these forest islands may serve as warming refuges in a fragmented landscape holding an invaluable diversity of species that, without these old-growth forest reservoirs, would be doomed to disappear.

On the availability of the recently proposed nomen Leptodactylus avivoca (Anura, Leptodactylidae)

In a recent contribution to the systematics of Leptodactylus Fitzinger, 1826 frogs endemic to the Brazilian campo rupestre (Carvalho et al. 2021), we revealed a genetically divergent lineage as an unnamed species distributed in the northern portion of the Espinhaço Mountain Range (EMR). The species was named and described as Leptodactylus avivoca in the taxonomic account section of the same paper, where a definition and diagnosis were provided to satisfy the provisions regarding the availability and validity of new nomina (see Chapters 4 and 6 of the International Code of Zoological Nomenclature, hereinafter the Code; Anonymous 1999). On that occasion, because of space limits imposed by the journal, we had to transfer most of the new species description into an Appendix, keeping in the main publication only the minimum requirements that would satisfy the rules and recommendations governed by the Code, thereby ensuring the availability and validity of the proposed new name. As a result of the transference from the main text to the Appendix, we ended up not taking notice that the species’ holotype had not been fixed in the main publication and appeared only as part of Appendix S1. Additionally, this Appendix was made available only as Online Supporting Material (Carvalho et al. 2021: Appendix S1) and not published alongside the main publication in the printed version. That rendered the proposition of Leptodactylus avivoca as originally published an atelonym (sensu Dubois 2011), i.e. an unavailable nomen (sensu Dubois 2000) as a consequence of the lack of explicit fixation of a holotype and statement of the collection where it was deposited in the main publication (Article 16.4 of the Code). In this paper, we intend to correct this nomenclatural oversight by proposing a new (homographic) nomen for the new Leptodactylus species, which corresponds to a genetic lineage endemic to the northern portion of the EMR, and also provide a definition and differential diagnosis in its own clade (L. plaumanni clade; sensu Carvalho et al. 2021).

ACTIVATED CHARCOAL APPLICATION FOR THE MICROPROPAGATION OF Cattleya crispata (Thunb.) Van den Berg

Micropropagation is an alternative for the genetic conservation and propagation of endemic species from “Campo Rupestre Ferruginoso”, such as the orchid Cattleya crispata. The aim of the present study is to assess the influence of activated charcoal on the in vitro germination, multiplication and elongation phases of C. crispata. Seeds extracted from mature capsules were used for inoculation in the culture medium that was adopted to assess the effect of supplementation, or not, with activated charcoal. Data about germination speed, seedling number, length, vigor, oxidation and contamination (bacterial and/or fungal) were assessed through these phases. Based on the results obtained, the use of activated charcoal was efficient in the in vitro germination and multiplication phases of C. crispata, providing greater speed and percentage of germination, less contamination and oxidation of the tissues, greater number, length and vigor of shoots, being effective for the genetic conservation and production of seedlings of the species. Culture medium without the supplementation of activated charcoal provided the best results for the in vitro elongation, with greater length, vigor and less oxidation of shoots.

PHENOLOGY, REPRODUCTIVE BIOLOGY AND SPATIAL DISTRIBUTION OF Chresta scapigera (LESS.) Gardner (ASTERACEAE)

Chrestas capigera (Less.) Gardner is an important medicinal herb which, however, has been poorly studied for its biology and ecology. This study aimed to investigate its phenology, floral biology, reproductive biology (self-pollination tests), spatial distribution and correlations between phenophases and climatic data in two sites (Cerrado stricto sensu and Campo rupestre) in southern Minas Gerais, Brazil. From August of 2012 to August of 2013, we monitored phenophase occurrence for 70 individuals: emission of new leaves, flowering, production of immature fruits, and mature fruits. Floral anthesis occurred during daytime and remained all day until fruit formation. Peak leaf emergence was observed in April, correlating with minimum monthly temperature and mean monthly precipitation. Flowering and green fruit peaked in May and June, respectively, and correlated negatively with all climatic variables. Mature fruits peaked in June, but did not correlate significantly with any of the climatic variables. However, no difference was found between the two sites regarding the timing of phenophases. The spatial distribution pattern of individuals within sites was random. The self-pollination tests showed that the individuals pollinated and fertilized themselves. Our findings allow us to conclude that the phenology of C. scapigera has pronounced phenological seasonality with reproductive peak activities in the drier and colder season, which is congruent with the self-pollination and anemochoric dispersion strategy.