Ferruginous Cave Research Articles

A New Genus of Prodidominae Cave Spider from a Paleoburrow and Ferruginous Caves in Brazil (Araneae: Prodidomidae)

A new monotypic genus of Prodidominae, Paleotoca gen. n., is proposed to include one cave species collected in a paleoburrow and ferruginous caves from Quadrilátero Ferrífero, Minas Gerais, Brazil: Paleotoca diminassp. n. (♂♀). The new genus is closely related to other Neotropical Prodidominae by sharing the classic claw tuft clasper. Paleotoca gen. n. is diagnosed by the absence of a dorsal abdominal scutum, a ventral parallel rows of strong spines on the tibia and metatarsus I–II, a lack of a conductor, a discrete median apophysis on the bulb and a bifid retrolateral tibial apophysis in the male palp, a posterior extension that is beak-shaped, and folds of a copulatory duct ventrally visible in the female epigyne. Like other Prodidominae species from caves, P. diminassp. n. is a troglobitic spider with morphological characteristics that indicate specialization to live in subterranean environments, including reduction in cuticular pigments, eye loss, heavy spination and trichobothria.

Larval and adult morphology of Photuris elliptica Olivier (Coleoptera, Lampyridae) and a Halloweeny case of cave-dwelling firefly larva feeding on bat guano

The predatory firefly Photuris elliptica is common throughout the Atlantic Forest and has been proposed as a biomonitor due to the species’ narrow niche and elevational range. However, the species is only known from adults, and a more effective monitoring of its populations hinges on the lack of knowledge on their immature stages. Recent sampling in ferruginous caves and inserted in other lithologies, on sites in the Atlantic Forest and Cerrado, have led to the capture of firefly larvae later reared to adults in the lab. Firefly larvae have been reported in South American caves before; however, they have only been identified to family due to the adult-biased taxonomy of Lampyridae. Here, we provide an updated diagnosis of Photuris elliptica, describe its immature stages for the first time, and update the distribution of the species. The larvae of Photuris elliptica were observed to interact with guano of several bat species, including that of vampire bats. These observations are consistent with the less specialized feeding preferences of photurine larvae, unlike most other firefly taxa, which specialize in gastropods and earthworms. It is yet unclear whether P. elliptica are cave specialists. However, since its occurrence outside caves remains unknown, protecting cave environments must be considered in conservation strategies for this important biomonitor species.

Three new subterranean species of the genus Speocera (Araneae, Ochyroceratidae) from caves of the Carajs area in the state of Par, Brazil.

Three new species of the spider genus Speocera Berland, 1914, collected in ferruginous caves in the Carajs region of Par state, Brazil are described: Speocera pinima sp. nov., S. babau sp. nov. and S. piquira sp. nov., all based on males and females. These are abundant species, which have morphological characteristics probably associated with isolation in the subterranean environment. Variation in the shape of the lateral eyes, which can be reduced, and in the eyes colloration bright or opalescent, were observed in all species in this study. These morphological variations may indicate that some populations are in the process of isolation and/or are distributed in different horizons of the subterranean environment, including the Milieu Souterrain Superficiel (MSS). An update of male and female genital structures and specializations to the subterranean environment are discussed.

16S rRNA Gene Amplicon Sequencing Data of the Iron Quadrangle Ferruginous Caves (Brazil) Shows the Importance of Conserving This Singular and Threatened Geosystem

The Iron Quadrangle (IQ) is one of the main iron ore producing regions of the world. The exploitation of its reserves jeopardizes the high biological endemism associated with this region. This work aimed to understand the diversity and bacterial potential associated with IQ caves. Floor and ceiling samples of seven ferruginous caves and one quartzite cave were collected, and their microbial relative abundance and diversity were established by 16S rRNA gene amplicon sequencing data. The results showed that ferruginous caves present higher microbial abundance and greater microbial diversity compared to the quartzite cave. Many species belonging to genera found in these caves, such as Pseudonocardia and Streptacidiphilus, are known to produce biomolecules of biotechnological interest as macrolides and polyketides. Moreover, comparative analysis of microbial diversity and metabolic potential in a biofilm in pendant microfeature revealed that the microbiota associated with this structure is more similar to the floor rather than ceiling samples, with the presence of genera that may participate in the genesis of these cavities, for instance, Ferrovum, Geobacter, and Sideroxydans. These results provide the first glimpse of the microbial life in these environments and emphasize the need of conservation programs for these areas, which are under intense anthropogenic exploration.

16S rRNA gene amplicon sequencing data of the Iron Quad-rangle ferruginous caves (Brazil) shows the importance of con-serving this singular and threatened geosystem

16S rRNA gene amplicon sequencing data of the Iron Quad-rangle ferruginous caves (Brazil) shows the importance of con-serving this singular and threatened geosystem

Potential Bioinoculants for Sustainable Agriculture Prospected from Ferruginous Caves of the Iron Quadrangle/Brazil

Biocontrol and plant growth-promoting bacteria (PGPB) are important agricultural bioinoculants. This study aimed to prospect new potential bioinoculants for a more sustainable agriculture from ferruginous caves of the Brazilian Iron Quadrangle. Culturable bacteria, from seven caves and one canga soil sample, were evaluated for biocontroller activity of the phytopathogens Xanthomonas citri subsp. Citri—Xcc306 (citrus canker), Fusarium oxysporum—Fo (fusariosis), and Colletotrichum lindemuthianum—Cl89 (bean anthracnose). The ability of the superior candidates to solubilize inorganic phosphate, fix nitrogen, and produce hydrolytic enzymes and siderophores was then analyzed. Out of 563 isolates, 47 inhibited the growth of Xcc306 in vitro, of which 9 reduced citrus canker up to 68% when co-inoculated with the pathogen on host plants. Twenty of the 47 inhibited Fo growth directly by 51–73%, and 15 indirectly by 75–81%. These 15 inhibited Cl89 growth in vitro (up to 93% directly and 100% indirectly), fixed nitrogen, produced proteases and siderophores, showed motility ability, produced biofilm, and all but one solubilized inorganic phosphate. Therefore, 15 (2.66%) bacterial isolates, from the genera Serratia, Nissabacter, and Dickeya, act simultaneously as biocontrollers and PGPBs, and could be important candidates for future investigations in planta as an alternative to minimize the use of pesticides and chemical fertilizers through sustainable agricultural management practices.

First molecular evidence of frogs as a food source for sand flies (Diptera: Phlebotominae) in Brazilian caves.

Genus and species of phlebotomine sand flies have been recorded and described in caves in Brazil, but no study has provided the food source used by sand flies in these environments. Herein, we identified the blood source used by sand fly species in caves located at "Quadrilátero Ferrífero" (QF), Minas Gerais state. Specimens were manually collected near or on anurans inside ferruginous caves in Serra do Gandarela National Park and Serra do Rola Moça State Park. Males and females were placed in vials with 70% alcohol and stored at -10°C. Females engorged, after specific identification, had DNA extracted and followed for PCR amplification using specific primers. Sequencing was analyzed in the GenBank and Barcode of Life. A total of 198 specimens were collected (107 females and 91 males), all of them belonging to species Sciopemyia aff. microps (88.89%), Sciopemyia sordellii (10.61%), or Martinsmyia oliveirai (0.50%). When it comes to the females, 89 were S. aff. microps and 18 S. sordellii. Nineteen engorged females of S. aff. microps were analyzed and most of them (n=18) presented blood from Bokermannohyla martinsi and one contained blood from Scinax fuscovarius. The blood present in engorged females of S. sordellii (n=4) was from B. martinsi. Sciopemyia genus specimens are commonly found in collections carried out inside natural caves, but this was the first study to prove that females of this genus feed on cold-blooded animals in nature. HIGHLIGHTS: • Here we proved that sand flies feed in cold-blooded animals in in Brazilian caves. • Females of the Sciopemyia genus were for the first time found feeding in natural habitats. • Anurans of the family Hylidae were identified as source by molecular analyzes. • Insect bloodmeal identification can help assessing the fauna in several biomes. • This is the first record of S. aff. micropsin caves of Brazil.

Complete mitochondrial genome of a cave dwelling Desmopachria (Insecta: Coleoptera: Dytiscidae) from the Eastern Amazon

Coleoptera presents most of the cave fauna biodiversity, with several troglobite species belonging to the aquatic family Dytiscidae. However, very little is known on both genetic and genomic diversity traits of Neotropical cave beetles. Thus, here we present the complete mitochondrial genome sequence of five specimens of Desmopachria collected in a ferruginous cave from Serra dos Carajás in Parauapebas (Pará, Brazil, Eastern Amazon). Besides the general characteristics of the mitogenome of the analyzed specimens, we present their phylogenetic position within the family, considering the available genome sequences of different subfamilies within Dytiscidae.

First description of the nesting site, nest, and eggs of the Rock Tapaculo (Scytalopus petrophilus)

Among the 44 known species of Scytalopus, only 25 have some type of reproductive information available. Here we present the first description of the nesting site, nest, and eggs of the Rock Tapaculo (Scytalopus petrophilus). The nest was registered inside a ferruginous cave located in the Serra do Gandarela National Park, Minas Gerais, Brazil. The closed nest containing two eggs was collected and consisted of cryptogams, grasses, and passerine remiges. The eggs were white and measured 23.0 × 16.3 mm, and 21.7 × 17.2 mm. Building of a new nest was recorded at the same collection site, in the next breeding season. Nesting season extended at least from October to February, and the nest site was reused within and between reproductive seasons. This suggest a strong local association between the species and the ferruginous caves and it reveals the need to preserve this environment which is currently threatened by mining activities.

Correlations of rock mass classifications applied to ferruginous caves

Abstract For the Brazilian iron ore mines, the presence of caves presents a challenge, since most of them are located within the ore deposit. The National Environment Commission (CONAMA 347 Resolution/2004) establishes that the speleological heritage, as well as its area of influence, cannot sustain irreversible environmental impacts. The physical integrity of caves adjacent to mining operations is an issue of pivotal importance to be scrutinised in studies towards the delimitation of the cave’s protection radius. This article presents the study of various models of correlation between the RMR and Q systems used for the stability assessment of natural iron ore caves. In order to study a correlation between the RMR and Q systems, the most popular rock mass classifications, and their application as a validation tool, a selection of measurements of Q and RMR, organized in a database from seven natural caves of ferruginous lithology, are submitted to a study and statistical analysis. An empirical equation was obtained from the data, using a simple linear regression. The result of the regression was compared with selected correlation equations and the best fit for the data was chosen. The best fit was the Rutledge & Pearson correlation equation, which presented the best combination of R² and S, after the equation created on basis of the real values for RMR, though the other equations have results similar to it. As the results were quite similar, the recommendation still is that correlations should be used with caution, and associated to other methods and field analysis.

Two new species of Neotropical land flatworms (Platyhelminthes: Continenticola) occurring in ferruginous and limestone caves

Compared to epigean domains, subterranean natural cavities are relatively stable environments. Among other invertebrates, land planarians have been sampled from caves in the Neotropical region, where their diversity seems to be high, but almost unknown. Besides being photophobic, land flatworms depend on the moisture of their microhabitats, since they do not have water-saving adaptations and, thus, caves seem to be an appropriate refuge for them. In the present study we describe two new species of Geoplaninae sampled from two types of cave lithologies: Pasipha carajaensis sp. nov. was sampled in ferruginous caves from the Amazonian biome and Pasipha tutameia sp. nov., in a limestone cave from the Cerrado biome. The new species differ from their congeners and from each other by the color pattern and characteristics of the copulatory apparatus. P. tutameia sp. nov. shows an inverted penis, a type of copulatory apparatus that is also known from another genus of Geoplaninae, among other triclads, but it is described for Pasipha for the first time. Considering that only a single specimen was collected in each cave and that both species are devoid of troglomorphic traits, we consider that their occurrence in caves might be occasional.

Landscape evolution in ferruginous geosystems of the Iron Quadrangle, Brazil: a speleological approach in a biodiversity hotspot

Natural subterranean caves represent a complex system, and studying them requires a holistic perspective considering their integration with the landscape. The vegetal cover around caves plays a key role in the energy input to the subterranean environment, mainly in caves associated with ferriferous formations, since the primary production by photosynthetic organisms is absent in such environments due to the permanent darkness. The current research aimed to characterize transitions in the composition of the surrounding landscape of a set of 235 ferruginous caves in the Iron Quadrangle, (Minas Gerais, Brazil) from 1984 to 2015, using information of remote sensors, geoprocessing techniques and concepts of landscape ecology. The analysis of landscape composition indicated a significant decrease in the conservation level of the study area (530 km2), which has lost 22.14% of the original vegetal cover. The conversion of native vegetation into anthropized areas in this period eliminated almost the entire protection radius of 15% of the caves known in the region, as well as committed the surrounding area of other 32%. This study demonstrated the need to develop scientific researches that relate the cave fauna and vegetal cover surrounding the caves, as well as the consequences that anthropic activities may cause to the subterranean environment.

Landscape Fragmentation around Ferruginous Caves of the Iron Quadrangle, Minas Gerais, Brazil

The aim of this article is to analyse the landscape fragmentation around ferruginous caves in the Iron Quadrangle (Minas Gerais, Brazil) and the conditions of environmental stability of the caves inserted in vegetal remnants under edge effects caused by anthropic activities. The methodology applied involved the implementation of three different landscape metrics to stablish the total area of patches, the area of the patches under edge effects (core area), and the distance from the nearest neighbour. The measurements were calculated considering classes of vegetal coverage (herbaceous, shrub, and arboreal vegetation) and then processed and combined by using map algebra to obtain the fragmentation degree, which was classified into three classes: high, moderate, and low. Results reveal that 62.88% of the vegetation coverage of the study area presents a low degree of fragmentation. Among the caves under edge effects, 15% obtained negative indices of environmental stability. Although most of the analysed caves are located in areas with a low degree of fragmentation, the proximity of anthropized areas and the risk they represent for the speleological heritage reinforce the need to create strategies focused on the conservation of the caves.Featured ideas: research article on the results of research carried out regarding the composition and configuration of the landscape surrounding ferruginous caves located in the Iron Quadrangle, in the state of Minas Gerais, Brazil.

Frequency of leucism in a colony of Anoura geoffroyi (Chiroptera: Phyllostomidae) roosting in a ferruginous cave in Brazil

Abstract: We provide the first report of the frequency of leucism for a species of Neotropical bat. Leucism is an anomaly of the skin pigmentation of an animal that manifests itself as the total or partial loss of the natural color of the species, and can affect part of or the entire body. During a study involving capture and marking individuals of a population of A. geoffroyi residing in a cave in the Brazilian state of Minas Gerais, seven individuals with some degree of depigmentation were recorded out of 616 individuals marked, for a frequency of 1.1%. Since leucism is due to recessive gene expression, these findings may indicate that the population is isolated and possesses a high level of endogamy. Factors that may be responsible for this condition in the studied population remain unknown.

Mammal tooth traces in a ferruginous cave in southeastern Brazil and their relevance to cave legal protection.

We describe the first occurrence of biogenic traces made by mammals within an iron formation cave located in the Serra da Ferrugem Ridge, in Southeastern Brazil. These bioerosions are tooth traces produced in boulders, walls and floor within the cave. The traces occur as sets of two or more grooves, which are highly variable in size. The grooves were compared to tooth traces artificially produced by imprinting the incisors of different mammal species collected in the cave region on soft clay. Among those, the following taxa are potential tracemakers: Akodon sp., Oligoryzomys sp., Necromys lasiurus, Rhipidomys mastacalis, Oecomys gr. concolor, Trinomys moojeni, and Hydrochoerus hydrochaeris. The age of the traces is unknown; therefore, any discussion on its fossil nature is circumstantial. Regardless of its relevance to paleontology, the presence of ichnological features should be considered as an additional cave value, according to the current Brazilian legislation regarding cave protection.

Coming out in a harsh environment: a new genus and species for a land flatworm (Platyhelminthes: Tricladida) occurring in a ferruginous cave from the Brazilian savanna.

Faunal inventories in ferruginous caves from an area belonging to the Brazilian savanna (Cerrado phytophysiognomy), on the eastern margin of the Serra do Espinhaço Plateau, in southeastern Brazil, have revealed the occurrence of land flatworms. Herein, a flatworm sampled in such subterranean environment is described as a new genus and species of the Neotropical subfamily Geoplaninae, Difroehlichia elenae gen. nov., sp. nov. The new genus shows rare features within Geoplaninae, namely sub-cylindrical body, poorly developed sub-epidermal musculature and a narrow creeping sole. Some features, such as a small body and a broad sensory margin in the anterior region of the body, as well as the fact that the holotype showed signs of recent copula, may indicate an adaptation to the subterranean environment, probably representing a troglophile. Difroehlichia elenae is characterized by an almost homogeneous dark brown pigmentation over dorsal surface and body margins, a short cylindrical pharynx, and a tubular and unforked intrabulbar prostatic vesicle, among other features. The holotype shows a secondary male copulatory organ located immediately behind the primary one, both communicating with the female atrium and gonopore canal. Since the species seems to have low abundance and restricted distribution and its type-locality is affected by mining activities, major concern arises regarding its conservation.

Description of Paracymbiomma gen. nov., a new genus of prodidomid spiders from the Neotropical region (Araneae: Prodidomidae) including a new troglobite species.

Paracymbiomma gen. nov. is proposed to include six new species from Brazil: P. angelim sp. nov. (♂ ♀) from São Paulo, P. carajas sp. nov. (♂ ♀), P. bocaina sp. nov. (♂ ♀) and P. caecus sp. nov. (♂ ♀) from Pará, P. doisirmaos sp. nov. (♂) from Pernambuco and P. pauferrense sp. nov. (♂) from Paraíba. The genus is included in Theuminae by having the sternum with posterior region without rebordered margins, strongly protruding between coxae IV and with numerous long and erect setae, and by the vulva with highly convoluted ducts. It can be distinguished from the other members of the subfamily by the male palp with paracymbium, single RTA, bulb with sclerotized conductor and partly sclerotized median apophysis, and by the female epigyne with posteromedian atrium and sclerotized margin, and vulva with copulatory ducts long, strongly convoluted laterally with proximal part (closest to copulatory openings) translucent. Paracymbiomma carajas sp. nov., P. bocaina sp. nov. and P. caecus sp. nov. occur exclusively in ferruginous caves. We provide a discussion on specializations and adaptations of Paracymbiomma gen. nov. and other species of Prodidomidae to the subterranean environment.

Searching for shelter in a ferruginous cave? A new species of Pasipha from a plateau in the Brazilian savanna (Platyhelminthes, Tricladida).

In a fauna survey in the eastern margin of Serra do Espinhaço Plateau, in an area belonging to the Brazilian savanna (Cerrado phytophysiognomy), a land flatworm was sampled in a ferruginous cave. Anatomical and histological analyses indicated that it belongs to a new species of the genus Pasipha, which is herein described. The new species shows an almost homogenous dark brown dorsal pigmentation, eyes spreading over the dorsal surface, a collar-shaped pharynx, and a prostatic vesicle with two portions separated by a canal. It differs from similar species mainly by anatomical and histological details of the ejaculatory duct, as well as male and female atria. The flatworm shows no troglomorphic traits and was collected once in the entrance zone of the cave. Hence, despite representing the first land flatworm species described from a Neotropical cave, we consider that its occurrence in the cave is probably occasional, using it as a shelter.

Cave lithology determining the structure of the invertebrate communities in the Brazilian Atlantic Rain Forest

In Brazil, only limestone caves and a few caves in sandstone, iron ore and granite rocks had their invertebrate communities evaluated. Being such, the present study aimed to promote a comparative analysis of the structure of the invertebrate communities in caves associated to carbonatic, magmatic, siliciclastic and ferruginous rocks of the Brazilian Atlantic forest. Significant differences in the relative richness, abundance and diversity were observed between lithologies. The average relative richness was higher in the ferruginous caves (0.53 spp). The total number of troglomorphic species was significantly different among caves and the highest average richness occurred at ferruginous caves (5.79 spp/cave). Siliciclastic, carbonatic and magmatic caves presented a higher quantitative similarity of the fauna. Ferruginous caves revealed communities with a fauna composition different from the other lithologies. The total richness of invertebrates correlated significantly and positively with the linear development in the siliciclastic caves (Rs = 0.67, P < 0.05), carbonatic (Rs = 0.71, P < 0.05) and ferruginous (Rs = 0.74, P < 0.05). The rock type in which the cave is inserted can determine differences in the richness of invertebrate troglophyles and troglobites. Therefore, on creating value attributes, the size of the caves should always come related to their lithology by the fact that same sized caves associated to different lithologies, possess communities with quite diverse structures.