Search Results (24)

Iron-ore extraction plays a central role in the global economy, but several major mining areas overlap with ecologically unique ferruginous landscapes in the Brazilian Amazon, including caves that harbor endemic and highly specialized invertebrate fauna. Reconciling mineral exploitation with biodiversity conservation requires objective ecological criteria capable of supporting evidence-based decision-making. In this study, we evaluated how cave attributes and surrounding landscape features jointly structure invertebrate communities in pristine ferruginous caves of the Amazon and assessed their relative importance and environmental thresholds. Invertebrates were sampled in 69 iron-ore caves during dry and wet seasons, and 28 environmental variables related to cave morphology, microclimate, trophic resources, lithology, vegetation cover, and external climate were measured in subterranean habitats and adjacent landscapes. Our results demonstrate a clear scale-dependent pattern: cave attributes primarily regulated species richness, troglobitic richness, taxonomic distinctness, and seasonal beta diversity, whereas landscape features exerted stronger control over species composition, including troglobitic assemblages. Threshold analyses identified specific combinations of cave and landscape attributes associated with biologically pristine communities. These findings highlight that assessments of ferruginous cave biodiversity must integrate landscape-scale metrics, be conducted in unaltered environments, and prioritize networks of caves rather than isolated sites. This integrative framework provides robust ecological support for conservation planning and the sustainable management of iron-ore cave systems in the Amazon. Full article

In this study, the astigmatid mite genus Troglocoptes Fain, 1966 is proposed as a junior synonym of Stereoglyphus Berlese, 1923. As a part of the project concerning identification of cave-dwelling mites in the Zagros Mountains, all ontogenetic instars of Stereoglyphus iranensis sp. nov. (Sarcoptiformes: Acaridae) are described from Doroodzan Cave, Fars Province, Iran. This is the second record of the genus in caves in the Palearctic region and the fifth described species worldwide. The morphological description is supplemented with DNA barcode data based on the mitochondrial cytochrome c oxidase subunit I (COI) gene, representing the first molecular data for this genus. Additionally, the first Asian record of Stereoglyphus longibursatus (Fain et Mahunka, 1990) is reported from Sahlak Cave, Fars Province, Iran. An identification key to the known species of the genus is provided. The troglobitic status of the new species is discussed, and the modifications of the anterior legs and tarsal setae, along with the partial reduction of idiosomal setation, are interpreted as adaptations to burrowing in bat guano. Full article

Subterranean ecosystems represent some of the most unique and fragile habitats on Earth, yet they remain poorly understood and highly vulnerable to human-induced disturbances. Despite their ecological significance, these systems are rarely integrated into conservation planning, and surface-level protected areas alone are insufficient to safeguard their biodiversity. In southeastern Brazil, a karst landscape spanning approximately 1200 km², recognized as the region with the highest cave density in South America (approximately 2600 caves), is under increasing pressure from urban expansion, agriculture, and mining, all of which threaten the ecological integrity of subterranean habitats. This study sought to identify caves of high conservation priority by integrating species richness of non-troglobitic invertebrates, occurrence of troglobitic species, presence of endemic troglobitic taxa, and the degree of anthropogenic impacts, using spatial algebra and polygon-based mapping approaches. Agriculture and exotic forestry plantations (54%) and mining operations (15%) were identified as the most prevalent disturbances. A total of 32 troglobitic species were recorded, occurring in 63% of the 105 surveyed caves. Notably, seven caves alone harbor 25% of the region’s known cave invertebrate diversity and encompass 50% of its cave-restricted species. The findings highlight the global significance of this spot of subterranean biodiversity and reinforce the urgent need for targeted conservation measures. Without immediate action to mitigate unsustainable land use and resource exploitation, the persistence of these highly specialized communities is at imminent risk. Full article

A new troglobitic species of Dalodesmidae, Pleonaraius spelaeus n. sp., is described from Rolo Vergara Cave, Neuquén Province, Argentina. This species represents the fourth known troglobitic member of the family, the first troglobitic species of Dalodesmidae recorded in South America, and the first known troglobitic millipede from Argentina. Pleonaraius spelaeus n. sp. is distinguished from its congeners by the absence of cuticular pigmentation and a unique combination of gonopodal characters. Ecological notes, a key, and a distribution map of Pleonaraius species are also provided. Full article

Three new species of Trichorhina are described from iron ore caves in the Serra dos Carajás Mountain Range, located in the Amazon Forest, Brazil. Trichorhina tucupi n. sp. occurs in Serra Leste, Serra da Bocaina and Serra do Tarzan Mountain Ranges. Trichorhina tacaca n. sp. occurs in caves in the Serra Norte Mountain Range. Trichorhina piloi n. sp. occurs in the Serra Sul and Serra Norte Mountain Ranges. Statistical methods were applied to investigate the putative morphological patterns of these species and to investigate their potential use in distinguishing Trichorhina species from epigean and hypogean habitats. Full article

Two new subterranean species of the genus Spelaeogammarus da Silva Brum, 1975 in Serra do Ramalho municipality, Bahia state, and Montes Claros municipality, Minas Gerais state, both in Brazil, are described herein. With these additions, the genus now comprises ten known species. This study includes a comparative table detailing the diagnostic characteristics of all Spelaeogammarus species and an updated genus diagnosis. Additionally, it provides insights into the species’ habitats and the threats they face. Some of the type localities mentioned in this study are not within protected areas, making these species particularly vulnerable to environmental risks. Threats primarily arise from surrounding land use, which can impact the water table and disrupt food resource availability. The discovery of these new troglobitic species underscores the urgent need for their inclusion in future threatened species assessments and highlights the importance of conservation measures to protect both the species and their cave habitats, along with the surrounding landscape. Finally, the discovery of these new species highlights the remarkable diversity of Spelaeogammarus in subterranean environments, emphasizing the need for further research and conservation efforts. Full article

Rhamdiopsis krugi is a highly specialized troglobitic (exclusively subterranean) catfish endemic to the phreatic water bodies of twelve caves located within two separated metasedimentary basins in the region of Chapada Diamantina, Bahia state, Brazil. This species is included in the List of Endangered Fauna of Brazil, under the Vulnerable category—VU. In general, troglobites have different strategies for searching for food and reproductive partners, as well as unique behaviors. Knowledge of the reproductive periods, as well as its feeding habits, provides fundamental data for effective protection and species conservation. Biological aspects related to feeding habits and reproduction of R. krugi were addressed across six annual cycles, considering both dry and rainy seasons. For this, stomach content analysis, using the frequency of occurrence and volumetric index methods, as well as observation of the sex ratio and stage of maturation of the gonads were carried out for 148 individuals of R. krugi sampled in eight caves in Chapada Diamantina. Stomach volumes correlated with reproduction aspects across the dry and rainy seasons. These populations showed opportunistic carnivorous feeding habits, consuming both autochthonous and allochthonous items, with a preference for foraging in submerged guano deposits, which demonstrates the catfish’s strong dependence on bats. Regarding sex ratios, there was no marked seasonality; however, in rainy seasons, there was a higher proportion of maturing females, showing a reproductive tendency. During these periods, there was also a significantly higher number of stomachs with contents, showing seasonality in the diet. Specialized diet and dependence on rainy periods, especially in diet, corroborate the fragility of R. krugi, especially considering the changes in rainfall regimes in Brazil, with dry seasons exceeding eight months per year in the last ten years. Full article

Cavernicolous scorpions are difficult to collect and study due to their often inaccessible habitats. Some have evolved unique morphological adaptations, known as troglomorphies, including reduced sclerotization and pigmentation, reduction and/or loss of eyes, attenuation and elongation of the appendages, which assist them to thrive in dark, humid and low-energy input environments. Cavernicolous scorpions are classified into accidentals, trogloxenes, troglophiles, and troglobites. The Balkans, and particularly the Dinaric Karst region, host a diverse cave-adapted fauna, including scorpions. Despite an 1895 report of a blind scorpion from Bosnia and Herzegovina, the first truly troglobitic European scorpion, Euscorpius studentium Karaman, 2020, was only described a few years ago, based on two immature specimens. In the present contribution, this unique species is redescribed based on the first adult specimens; the ecological classification of all currently known cavernicolous Euscorpiidae Laurie, 1896, is updated; a key to the identification of cavernicolous scorpions occurring in the Dinaric Karst is provided; and the historical and geographical factors affecting the distribution and conservation of cavernicolous scorpions in the Balkans is reviewed. Full article

The most studied cavefish in the world is Astyanax mexicanus, and the most frequently used specimens in research come from the Pachón cave in Northeast Mexico. A recent study using the capture–mark–recapture technique revealed that the Pachón population size is only in the hundreds of individuals, not in the thousands. This result raises serious concerns about their long-term survival and highlights the need to accurately estimate the population size of other Astyanax caves. In our study, we used a well-established, non-invasive method for estimating population size: the transect sampling method, which counts the abundance of organisms along a line at regular intervals. We used the 310 m long Sabinos Cave’s Pool #1 for measurements and estimated a population of 1142 individuals. Most importantly, we found that cavefish are not distributed uniformly: 68% of the individuals were clustered under a bat roost. To corroborate this observation, we used drones to explore submerged galleries inaccessible to scientists. Results from the Toro/Calera Cave system confirmed that most galleries were essentially void of cavefish, except for in those few areas with high amounts of nutrients. Scientists visiting the most studied Astyanax localities (Pachón, Sabinos, Tinaja, and Chica) experience what appear to be high-density populations of about 10 fish/m², possibly because the pool they visit happens to be under bat roosts. Our study shows that one cannot extrapolate the density at these localities to the rest of the habitat, where densities might be two orders of magnitude lower. Future studies should consider that the apparent high density at visited sites is overrepresenting the total population size when calculating the number of fish specimens to be captured. Full article

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. Full article

The Balkan region is rich in limestone deposits, which have created one of the largest hotspots of subterranean biodiversity. This paper gives an overview of the diversity of subterranean terrestrial arthropods in Resava Cave in eastern Serbia. This cave is protected and has the status of a natural monument. At the same time, it is one of the most visited caves in Serbia and its surroundings. Our study comprises the results of three years of biospeleological investigations of the famous Serbian cave in combination with data from the few available literature sources on the arthropod fauna of the cave. The arthropod samples were collected both manually and with pitfall traps. A total of 107 arthropod species from the four major subphyla were registered in the cave: 66 species of Hexapoda, 27 species of Chelicerata, 11 species of Myriapoda and three species of Crustacea. For four troglobitic, 16 troglophilic and 87 trogloxenic species recorded in the cave, descriptions of their microhabitats and information on their distribution in the cave are given. Considering the medium size of Resava Cave and the lack of permanent water flow in the two main levels on the one hand, and the large number of arthropod species recorded on the other, the cave is relatively rich in hypogean terrestrial arthropod fauna compared to other caves in Serbia that have been biospeleologically studied so far. Full article

Spelaeometra Polhemus & Ferreira, 2018 (Hemiptera: Heteroptera: Hydrometridae) is a monotypic and troglobitic genus, recently described based on material collected in the state of Minas Gerais, Brazil. From specimens collected in the Gruna do Enfurnado Cave in the Serra do Ramalho karst area, municipality of Coribe, state of Bahia, Brazil, we describe Spelaeometra hypogea Cordeiro & Moreira, sp. nov. and compare it with Spelaeometra gruta Polhemus & Ferreira, 2018. The new species is diagnosed by the general body color being pale-yellow to light-brown; antennal segments I and II being subequal in length; the reduced gular lobe, not covering any labial segment; the male proctiger without apical projections; and the male paramere with convex dorsal margin after the curvature, with a narrow hook-like apex. Full article

The caves of Igatu, municipality of Andaraí, belonging to the region known as Chapada Diamantina represent a new hotspot of subterranean fauna. These caves are siliciclastic, which are sedimentary rocks where silica predominates, such as sandstones and (following metamorphism) quartzites, which makes them even more relevant from the point of view of subterranean diversity. For five caves, which we named Igatu Cave System (ICS), thirty-seven obligate cave species were found, of which thirty-five were troglobitic and two were stygobitic. The troglobitic taxa for ICS belong to three phyla, nine classes, 18 orders, and 32 families, representing a high phylogenetic diversity. Some taxa were, for the first time, reported as troglobitic in Brazil and even worldwide, such as Acari and scutigeromorphans (Chilopoda). We started the studies in 2009 and continue trough long-term monitoring projects. Some threats, severe in the past, such as “garimpo’’ (illegal small-scale artisanal mining) continue nowadays in an incipient way; however, the urban expansion due to the touristic appeal is also considered a threat. Our data ranked ICS as the Brazilian hotspot with the highest number of troglobitic/stygobitic species. Full article

We here provide the first comprehensive analysis and discussion on prey consumed by the European cave salamanders of the genus Speleomantes. Our study stems from the need to shed light on the still unknown foraging behavior adopted by Speleomantes cave salamanders. Starting from the published datasets on gut contents from all Speleomantes species (including hybrids), we here discuss additional information (i.e., species ecology, lower taxonomic level), which were systematically omitted from those data sets. We analyzed a data set consisting of 17,630 records from 49 categories of consumed prey recognized from gut contents of 2060 adults and juveniles Speleomantes. Flying prey accounted for more than 58% of the prey items, while elongated crawling prey accounted for no more than 16% of the diet within a single population. Among the total recognized prey items, only three can be surely ascribed to the group of strictly-cave species (i.e., troglobites), meaning that European cave salamanders mostly forage in surface environment, and therefore represent one of the major drivers of allochthonous organic matter in subterranean environments. Some of the consumed prey seemed to be aquatic, allowing us to hypothesize whether Speleomantes are able to catch prey from a shallow body water. Furthermore, European cave salamanders possess the ability to prey upon taxa characterized by particular anti-predator defenses, while morphological constraints seem to be the most important limit to prey consumption. For each specific case, we provide insights and propose hypotheses concerning the foraging behavior that need to be tested to properly understand the foraging behavior of this cryptic salamanders. Full article

Subterranean karst caves can contain unexpected biodiversity, but few studies related to spider population genetics have been conducted in the karst area of Southern China. In this study, we investigated the population genetic structure of Trogloneta yunnanensis (Song & Zhu, 1994) based on 73 spider samples from six underground populations in South China Karst. Population genetic structure analysis showed a clear divergence (F_ST > 0.9 and Nm < 0.05) among populations according to mitochondrial genes. The phylogenetic gene tree constructed by BI and ML methods recovered six geographic clades. Divergence time estimation indicated that the divergence of these six populations can be traced back to the late Pleistocene. We supposed that the geographic isolation led to the extreme population structure. According to this study and previous studies about troglobites living in this region, the subterranean habitats of the Yunnan-Guizhou Plateau may contain many organisms with similar genetic structures. The subterranean biodiversity in the karst area of Southern China needs to be re-evaluated and protected. Full article