Rodrigo Lopes Ferreira

The entrance as a complex ecotone in a Neotropical cave

Cave entrances are transition zones with intermediate characteristics between epigean environments, which bear lower environmental stability, and hypogean environments, with lower food resources. Associated to these interfaces there is a specific community, capable of exploiting its unique and intermediate characteristics. This work investigated this community in a Brazilian limestone cave, identifying its arthropod species composition and spatial distribution, and exploring its relationships with climatic and structural environment characteristics and trophic relations. An ecotone zone was identified, with 55 species found only in the ecotone, 49 species were shared with the epigean community, 37 species with the hypogean community, and 14 species were found in the three communities. Although detritus is the base of the trophic web in the entrance, light allows the establishment of some producers and even herbivores. Species diversity in the ecotone was intermediate to that of the adjacent environments. Light is the main filter that acts near the cave entrance and determines the presence and distribution of several species in the ecotone. Therefore, this region is important for the cave ecosystem as a whole, considering that a considerable amount of trophic resources is transferred from the epigean to the hypogean environment through this area. Accordingly, conservation and management strategies regarding cave communities should incorporate actions to study and protect ecotonal communities.

Aspects of the population ecology of Goniosoma sp. (Arachnida Opiliones Gonyleptidae) in limestone caves in southeastern Brazil

The new species of Goniosoma found in the city of Pains, Brazil, is well distributed in the caves of the region, occurring in 55 out of 62 visited caves. The species is still being described. This study aimed to evaluate oscillations in population sizes and to show possible allometric variations between individuals. The caves presented more constant temperature and relative humidity than the external environment. In Dona Rita cave the population of Goniosoma sp. varied between 48 and 140 individuals; in São Lourenço cave, between 45 and 346 individuals; in Isaias cave, between 93 and 509 individuals, and in Sorvetão cave, between 27 and 125 individuals. Despite the different sizes, the populations presented similar oscillations, reaching maximum values in June and July and then decreasing until october. No migration events were observed between the nearest caves, about 250 m apart. The species is trogloxen, leaving the cave regularly to feed on the nearest trees and rocky walls and returning in the morning. A Principal Components Analysis (PCA) revealed a sexual dimorphism in the size of the second leg and its femur, the males with average leg length of 16 cm and femur length of 4.5 cm and the females with average leg length of 9 cm and femur length of 2.5 cm.

Biodiversity under rocks: the role of microhabitats in structuring invertebrate communities in Brazilian outcrops

There is little knowledge on the factors that can structure communities of tropical arthropods that live under rocks (lapidicolous communities). Using 28 rock shelters in a small granitic outcrop, we examined the relations among area, inclination, organic matter content, substrate moisture and distance from the border of the outcrop and richness and diversity of the communities. In total, we collected 1216 individuals from 106 morphospecies of Araneida, Acarina, Polyxenida, Spirostreptida, Dermaptera, Neuroptera, Orthoptera, Dictyoptera, Psocoptera, Coleoptera, Hymenoptera, Diptera, Embioptera, Homoptera, Isoptera, Heteroptera, Lepidoptera, Collembola, Nematoda and Oligochaeta. The richness and diversity of the lapidicolous communities were significantly correlated with area, inclination and distance from the edge of the outcrop in the dry season. The richness and diversity of lapidicolous communities were significantly correlated with organic matter, substrate moisture and area in the rainy season. Space availability seemed to be an important structuring factor for lapidicolous communities in the present study, the most significant variables (substrate moisture and organic matter) were related to shelter area.There is little knowledge on the factors that can structure communities of tropical arthropods that live under rocks (lapidicolous communities). Using 28 rock shelters in a small granitic outcrop, we examined the relations among area, inclination, organic matter content, substrate moisture and distance from the border of the outcrop and richness and diversity of the communities. In total, we collected 1216 individuals from 106 morphospecies of Araneida, Acarina, Polyxenida, Spirostreptida, Dermaptera, Neuroptera, Orthoptera, Dictyoptera, Psocoptera, Coleoptera, Hymenoptera, Diptera, Embioptera, Homoptera, Isoptera, Heteroptera, Lepidoptera, Collembola, Nematoda and Oligochaeta. The richness and diversity of the lapidicolous communities were significantly correlated with area, inclination and distance from the edge of the outcrop in the dry season. The richness and diversity of lapidicolous communities were significantly correlated with organic matter, substrate moisture and area in the rainy season. Space availability seemed to be an important structuring factor for lapidicolous communities in the present study, the most significant variables (substrate moisture and organic matter) were related to shelter area.

New records of Ixodes paranaensis (Acari: Ixodidae) from Minas Gerais, southeastern Brazil

Abstract Ixodes paranaensis is a little-known tick species recently described from specimens collected in Quatro Barras, State of Paraná, southern Brazil. The present report describes the collection of three males and three females of I. paranaensis from a quartzite cave (Gruta dos Fugitivos) in the municipality of Santa Rita de Ibitipoca, State of Minas Gerais, southeastern Brazil. This new record extends the known distribution of I. paranaensis and clarifies our knowledge of the male, which was originally described from a single deformed specimen.

Two new troglobitic species of Oxarthrius Reitter (Coleoptera, Staphylinidae, Pselaphinae) from Brazil

Two new species, Oxarthrius inexpectatus and Oxarthrius aurora, are described from caves in Minas Gerais and Tocantins states in Brazil, respectively. The major diagnostic features are illustrated and a key to the known species from Brazil is given.

Annotated checklist of Gonyleptoidea (Opiliones: Laniatores) associated with Brazilian caves

In Brazil, the order Opiliones has been well studied, making this country the leader in research with the group, but few extensive works have been made on the distribution of harvestmen associated with caves. In this context, the present paper aims to list all records of the superfamily Gonyleptoidea associated with Brazilian caves, using records from the literature and unreported data from scientific collections. The compiled checklist contains the largest number of harvestmen species recorded for caves in one country, worldwide. A total of 155 species belonging to 7 families were recorded from 952 caves throughout 152 municipalities and 17 states of Brazil. A considerable number of 46 putative (undescribed) new species were recognized, including 9 troglomorphic species. Additionally, 161 new municipal records where found for 58 known species. The most diverse family was Gonyleptidae (104 spp.), with the subfamilies Pachylinae (55 spp.), followed by Goniosomatinae (18 spp.) and Mitobatinae (16 spp.). The number of described species analysed in the present work represents about 12% of the Brazilian opiliofauna of Gonyleptoidea, with many species widely distributed, being indicative of affinity of the group with the cave environments. Thus, the compilation of distribution data of such species (mainly the troglobitic and troglomorphic) can directly contribute to a higher valuation of their habitats, leading to better preservation policies, as well as being useful for future ecological and biogeographical studies.

Description of a second South American species in the Malagasy earwig genus Mesodiplatys from a cave habitat, with notes on the definition of Haplodiplatyidae (Insecta, Dermaptera)

Abstract The genus Mesodiplatys (Dermaptera: Diplatyidae) comprises eight species from Madagascar and one species from Peru. Based on a sample collected from a cave in Brazil, a new species of this genus, Mesodiplatysfalcifer Kamimura, sp. n., is described as the second species from South America. Based on a reexamination of the holotype of Mesodiplatysinsularis, a revised key to Mesodiplatys species is provided. The definitions of the genera Mesodiplatys and Haplodiplatys and the family Haplodiplatyidae are also reconsidered.

A novel symbiotic relationship between mites and recluse spiders (Sicariidae: Loxosceles), with a description of a new Callidosoma species (Trombidiformes: Erythraeidae)

This study reports a symbiotic association between an unknown species of Loxosceles (Araneae: Sicariidae) and the adults of a new species of parasitengone mite that lives on their web in Brazilian caves. This mite is described as Callidosoma cassiculophylla sp. nov. (Parasitengona: Erythraeidae). The symbiotic association is clearly beneficial for the mite, which lives with the spider, and feeds on prey captured by their webs, without any aggressive behavior or expulsion of the mites by the spiders.

Screening of antifungal susceptibility in cave-dwelling aspergilli and report of an amphotericin B-resistant Aspergillus flavus

*maresend@icb.ufmg.br Citation:

Autômatos Celulares aplicados ao estudo de Dinâmica Populacional de Fauna Cavernícola

Automatos celulares sao uma das formas de modelagem aplicada para estudo de diversos fenomenos naturais, dentre eles destacam-se as dinâmicas populacionais [3]. Ainda existe pouco conhecimento sobre as caracteristicas populacionais de especies que habitam sistemas cavernicolas [1] [2] [4]. Portanto, automatos celulares podem representar uma metodologia util para um melhor entendimento sobre essas especies e suas dinâmicas, por permitirem que as caracteristicas individuais sejam utilizadas para estudar o comportamento do individuo e da populacao a qual pertence. Dessa maneira, pode-se obter maiores informacoes sobre o sistema natural e seu funcionamento ecologico. Os dados analisados correspondem a distribuicao espacial e temporal de dez especies encontradas em uma caverna em sistema ferruginoso. Essas especies estabelecem interacoes ecologicas entre si, destacando-se a competicao e interacao predador-presa. As amostras foram coletadas a cada tres meses, durante dois anos, com levantamento detalhado da fauna existente na cavidade. O objetivo deste trabalho e representar os individuos de cada especie no formato de automato celular, avaliando a evolucao do sistema e sua dinâmica por meio de parâmetros modelados como: abundância populacional, preferencia alimentar, preferencia de regiao, tamanho do passo de deslocamento e tempo de evolucao. A abundância populacional corresponde ao tamanho da populacao de cada especie estudada. Ja a preferencia alimentar representa a interacao predador-presa, indicando a presa de preferencia do predador. A preferencia de regiao modela a regiao dentro da caverna na qual cada animal prefere permanecer, sendo esse parâmetro obtido por meio da analise espacial dos dados das amostragens. O tamanho do passo corresponde ao deslocamento do animal seguindo o movimento browniano em duas dimensoes. Ja o tempo de evolucao corresponde ao tempo de evolucao do sistema, sendo considerado em um primeiro momento o tempo correspondente ao desenvolvimento do experimento e das amostragens. Os dados reais permitiram a verificacao dos resultados gerados pelos automatos e tambem o ajuste adequado dos parâmetros utilizados. Como resultado preliminar das simulacoes, destaca-se a difusao dos animais pela cavidade, considerando a relacao predador-presa, de forma semelhante ao caso real. A interacao entre presas e predadores foi verificada, sendo que areas com grandes concentracoes de presas funcionaram como atratoras para os respectivos predadores. Tambem foi possivel identificar o efeito da competicao entre predadores que possuiam presas em comum. A modelagem empregada permitiu a avaliacao do espalhamento desses animais no interior da caverna, contribuindo para um melhor entendimento das dinâmicas populacionais dessas especies. Tal fato auxilia na proposta de estrategias de manejo mais efetivas para a preservacao de especies cavernicolas e do sistema ecologico como um todo. O modelo ainda esta em desenvolvimento e espera-se que um refinamento nos parâmetros possam ser obtidos a partir do estudo dos dados de distribuicao espacial com o uso de tecnicas de Estatistica Espacial. Esses estudos indicarao padroes que poderao ser comparados com as simulacoes, permitindo uma melhor avaliacao do modelo proposto.