Search Results (31)

Arrhopalites Börner, 1906 includes 40 valid species, with 20 considered troglobionts, exclusive to caves. Arrhopalites beijingensis sp. nov. is the third species from China and the first from a cave habitat, collected in the Xianrendong Cave, Beijing, Junzhuang Town. It resembles several species of the Caecus group, possessing spine-like chaetae on the head, five to seven subsegments on Ant IV with annulated separations, and lacking cuticular spines on Abd VI; it differs from these species in its various characteristics. The mitogenome of A. beijingensis sp. nov. was assembled (14,774 bp in length), marking the first made available from the genus. Due to the incipient number of published mitochondrial genomes of Symphypleona, we downloaded raw sequencing data and performed the assemblies and annotations of 11 species. Our phylogenetic analyses comprised 24 mitogenomes in total; of those, 22 were of Symphypleona and 2 were of outgroups. A. beijingensis sp. nov. was placed closer to Pygmarrhopalites spinosus (Rusek, 1967), with high support. Arrhopalitidae was found as a sister group to Katiannidae, both part of Katiannoidea. The two species of Sminthuridida were placed as a sister group to all other Appendiciphora. More systematic analyses and enhanced sampling from key lineages are needed to better understand Symphypleona’s internal relationships and evolution. Full article

Subterranean environments are often characterized by a natural gradient of microclimatic conditions and trophic resources, showing a higher trophic availability and a lower microclimatic stability in the shallowest area (close to the cave entrance), while the opposite occurs in the deepest sections. The shallowest areas of subterranean environments (e.g., the entrance and twilight zone, Mesovoid Shallow Substratum) act as ecotones between the surface habitats and the deep areas, creating a particular habitat which can be exploited by numerous species with different degrees of adaptation to subterranean environments. Species living in these ecotones may hold a key role in sustaining the entire ecosystem, as they are likely one of the major drivers of allochthonous organic matter. Indeed, these species are usually facultative cave-dwellers, meaning that they are able to exit and forage on the surface. Once these species are back inside the cave, they provide the local community with different typologies of organic matter (e.g., feces, eggs), which represent one of the most important sources of organic carbon. Therefore, studying which ecological features may exert significant effects on the abundance of these species may be of great help in understanding the ecosystem dynamics and the functional role of each species. In this study we analyzed the data collected through a year-round monitoring program, aiming to assess the potential effects that both abiotic and biotic features may have on the abundance of three facultative cave species. We focused on seven caves located in Monte Albo (Sardinia, Italy). The cave environments were divided into 3-meter sectors, and within each cave sector, microclimatic and biological data were seasonally recorded. We focused on the following facultative cave species: the spiders Metellina merianae and Tegenaria sp. and the snail Oxychilus oppressus. Different relationships were observed between the ecological features and the abundance of the three species. The two spiders were more abundant in warmer cave sectors closer to the cave entrance, especially the M. merianae. On the other hand, the snail tended to be more abundant farther from the cave entrance and in more illuminated cave sectors, probably because sunlight promotes the abundance of some of its trophic resources (e.g., lichens, vegetation). Furthermore, O. oppressus was the only species whose abundance and cave distribution was significantly affected by seasonality. This study provides useful and novel information to understand the population dynamics of facultative cave species and their role in subterranean ecosystems. Full article

The genus Trogolaphysa comprises 81 described species distributed across the Neotropical and Afrotropical regions. In the Americas, just over half of the species found in subterranean habitats have a reduced eye number (0–5 eyes). Subterranean species are of interest as models to study the evolution of morphological adaptations. Many subterranean species of Trogolaphysa were described before the introduction of chaetotaxy as a diagnostic tool and thus remain incompletely described and diagnosed. To identify gaps in descriptions and facilitate the identification of newly collected forms, we provide standardized summary descriptions, species diagnoses, diagnostic tables, and a dichotomous key to the 33 Neotropical species of Trogolaphysa with reduced eye number. As a result of this synthesis, we describe two new troglobiontic species, Trogolaphysa reneaui n. sp. and Trogolaphysa welchi n. sp. from Belizean caves. Full article

Located in Lestelas-Balaguères massif, central northern Pyrenees, France, the Baget catchment covers 13.25 km² and is highly karstified: so far, more than 80 caves have been recorded. The main outlet of the system, the exsurgence de Las Hountas, has an average flow of 550 L/s. Downstream, it is connected with the hyporheic of the Lachein stream. The Baget system, formed by both the karstic system and the hyporheic, has been intensively investigated by cave biologists and is known to be a hotspot for subterranean biodiversity. The synthesis provided here lists no less than 17 troglobionts and 40 stygobionts, with 3 single site endemics, making the Baget system the richest subterranean hotspot in the Pyrenees. This is notably due to the diversity of subterranean habitats and to the comprehensive knowledge of the stygofauna, likely unmatched at the European scale. Considering the significant speleological findings of the last 15 years that have not been yet biologically investigated, we can expect new discoveries, especially for the troglofauna. Full article

The South of France is a biodiversity hotspot within Europe. Here, we present a comprehensive review of surveys conducted in the Cent Fonts aquifer, an overlooked subterranean biodiversity hotspot embedded in a region rich in stygobiotic species and threatened by climate change and water abstraction projects. Key studies, spanning from 1950 to 2006, show a progression in survey methods and results, although troglobiotic species remain poorly documented. With 43 stygobiotic species recorded, the Cent Fonts is the richest stygobiont hotspot in France. Most species are regional endemics, a quarter of which are considered vulnerable by the IUCN. The Cent Fonts also hosts several relict species and is the type locality of four species. Such a high biological value clearly deserves to be preserved. Our analysis warns of a possible decline in biodiversity, as eight of the species recorded in the 20th century were absent from the 2006 survey, suggesting potential threats of unknown origin. The capture of the Cent Font springs for water abstraction is discussed as a potential threat to this ecosystem and its unique biodiversity. Three new species of stygobiotic molluscs are described, one of which was collected in the Cent Fonts. Full article

In the Lessini Mountains, the southernmost prealpine area in the Veneto region, thousands of caves are found, many of which have been extensively studied from the biological point of view. Numerous studies have been carried out on taxonomic and biogeographic aspects over the last hundred years. Two caves, in particular, have been found to be extremely rich in species adapted to life in subterranean environments. These are the Arena Cave in the Monti Lessini Veronesi and the Buso della Rana cave system in the Monti Lessini Vicentini. The two caves have extremely different development: Arena Cave is about 100 meters in length, and the Buso della Rana-Pisatela cave system is more than 37 km in length. Despite this huge difference in size, they both have the highest number of subterranean dwelling species in northern Italy (16 troglobionts and 8 stygobionts in Arena Cave, and 7 troglobionts and 11 stygobionts in the Buso della Rana-Pisatela cave system). Full article

The Água Clara Cave System was previously recognized as a prominent hotspot of subterranean biodiversity in South America, harboring 31 cave-restricted species. However, a recent expedition conducted in September 2023, coinciding with an exceptionally dry period in the region, provided access to previously unexplored areas. Therefore, the objective of this research was to investigate the cave-restricted invertebrate species, extending the findings from a previous article on the Agua Clara Cave System published in June 2023, and emphasizing the significance of this system as one of the most crucial tropical biodiversity hotspots. This survey unveiled an additional 10 species, raising the count of cave-restricted species within the system to an impressive 41. This remarkable diversity not only solidifies the Água Clara Cave System’s position as a paramount hotspot of subterranean biodiversity in the tropics but also serves as a stark warning about the imminent risks faced by these species. The escalating human-induced alterations in the region, notably deforestation, pose a significant risk to the survival of many of these unique and endemic species. Full article

Why do the eyes remain comparatively large, whereas the cornea is reduced in most troglobiont mysids? Are there any important organ size-dependent functions served by non-visual eye rudiments? This issue was approached by measuring eye structures in five troglobiont species of Mysida and two Stygiomysida compared with 14 troglophiles and 49 trogloxene Mysida species. The Organ of Bellonci (OB) was found in all Mysida and, as first records, also in Stygiomysida. The length of OBs increased with individual body length (BL) and eye length (EL) in four examined species: from postnauplioid larvae to adult stage in a troglophile and a trogloxene mysid species examined; and from juveniles to adults in a troglobiont mysid and a troglobiont stygiomysid. At the interspecific level, EL was, on average, 26% shorter at a given BL, while the OB was 40% longer at a given BL and 54% longer at a given EL, respectively, in adult troglobionts compared with trogloxene mysids. The OB is clearly proliferating, while the cornea is reduced in troglobionts. This points to sensory functions (possibly together with other functions). The sensory pore organ was found in all 15 Mysida species whose eyes were mounted on slides, and the first record of this organ was also found in Stygiomysida. Full article

The Doi Chiang Dao massif, which became a UNESCO Biosphere Reserve in 2021, is the highest karst mountain in Thailand. Tham Chiang Dao cave is located at the foot of this massif and is among the best-known caves in Thailand, having been visited since prehistoric times, and being a sacred place for the local Shan and Thai people. The cave consists of five main interconnected passages with a total length of 5342 m which ranks it as the 11th longest cave in Thailand. Tham Chiang Dao is the best studied cave in Thailand with a long series of explorations, investigations and zoological collecting. Here, we summarize the 110 years of biological exploration and investigation devoted to this cave. A total of 149 taxa have been recognized in Tham Chiang Dao, of which 61 have been identified to species level. The cave is the type locality for 14 species. The obligate subterranean fauna includes 37 species, of which 33 are troglobionts and 4 are stygobionts. Conservation issues are addressed in the discussion. This work is intended to provide a reference for the knowledge of cave fauna of the Chiang Dao Wildlife Sanctuary and a tool for its management by the local cave management committee, the National Cave Management Policy Committee, and the Department of Mineral Resources. It also documents the biological importance of Tham Chiang Dao in the Doi Chiang Dao UNESCO Biosphere Reserve. Full article

The southern part of the Mekong Delta Limestones of Vietnam (MDL-HC or Hon Chong karst) comprises numerous small limestone hills. It is a hotspot of biodiversity for soil and cave invertebrates. Here, we synthesize the results of biological surveys carried out in Hang Mo So, the richest MDL-HC cave for troglobionts, and in surrounding karsts. Methodologies for the ecological characterization of species are discussed, with emphasis on parallel sampling (external soil plus cave). Hang Mo So has 27 troglobionts, including many still undescribed. An additional 40 cave-obligate species are known from other caves of MDL-HC. Among them, several are expected to be found in Hang Mo So. Most troglobionts of MDL-HC are endemic. Several relictual taxa without close relatives in Southeast Asia occur in Hang Mo So and in MDL-HC, reflecting an ancient origin of the fauna. The reasons for this richness are uncertain, but the cause of its current destruction—quarrying—is all too evident. Most of the original 4 km² of the MDL-HC karst has been destroyed or soon will be, ultimately leaving only 1.6 km² unquarried. Endemic species linked to karst habitats are, therefore, under clear threat of extinction. The Hon Chong karst (MDL-HC) was listed among the ten most endangered karsts on the planet 25 years ago. Today it would probably top the list. Full article

The Western Balkan’s Vjetrenica Cave in southern Bosnia and Herzegovina is renowned for high richness of subterranean species. However, the data on its fauna have been published only in monographs printed in a small number of copies, making them hardly accessible to the wider scientific community. To overcome this issue, we compiled the data from published monographs with the data from our own recent field surveys. Further, as they are connected via water channels or small crevices in bedrock, we defined the Vjetrenica Cave System as a system comprising Vjetrenica and Bjelušica Caves and Lukavac Spring. Altogether, 93 troglobiotic, i.e., obligate subterranean aquatic (48) and terrestrial (45), taxa were reported for the system, verifying the Vjetrenica Cave System as the second richest locality in subterranean biodiversity in the world. The global uniqueness of the system is also reflected in the fact that as many as 40 troglobiotic species were described from the system. Finally, we reviewed the factors endangering this unique subterranean community and questioned whether it will withstand human-induced changes and pressures due to infrastructural development in southern Bosnia and Herzegovina. Full article

China is a country with abundant karst landscapes, but research on cave biodiversity is still limited. Currently, only Ganxiao Dong, located in Huanjiang, Guangxi, has been reported as a hotspot for cave biodiversity. Many of the world’s most troglomorphic species in the major groups of cave animals have been recently discovered in China, making the existence of many more hotspots in the country likely. Feihu Dong, one of these potential hotspot caves, has been systematically investigated to complement a preliminary species list of 1995, leading to the discovery of 62 species of animals from the cave. Among them, 27 are considered troglobionts or stygobionts, 26 are considered troglophiles or stygophiles, and nine are classified as trogloxenes or stygoxenes. Research on the cave biodiversity of Feihu Dong has demonstrated that it currently holds the highest number of known cave animal species in China. Among the most remarkable features of this fauna is the co-occurrence of five species of cave-obligate beetles, all modified for cave life. The biological survey was limited to a small part of the cave. Several habitats (like guano) have not been investigated so far, and several important cave groups have been insufficiently or not sampled (like Ostracoda). Meanwhile, the system increases in length with each new caving expedition. Further discoveries of cave organisms in Feihu Dong are therefore expected. As Feihu Dong and Ganxiao Dong are the only caves in China that have been extensively studied for a large range of organisms, and as they are located in karstic areas that are similar in richness to other regions of southern China, it can be confidently assumed that several other caves of high biodiversity will be discovered in the coming years. Full article

The Crystal-Wonder Cave System developed in the Western Escarpment of the southern Cumberland Plateau in the Interior Low Plateau karst region of south-central Tennessee, USA is a global hotspot of cave-limited biodiversity. We combined historical literature, museum accessions, and database occurrences with new observations from bio-inventory efforts conducted between 2005 and 2022 to compile an updated list of troglobiotic and stygobiotic biodiversity for the Crystal-Wonder Cave System. The list of cave-limited fauna includes 31 species (23 troglobionts and 8 stygobionts) with 28 and 18 species documented from the Crystal and Wonder caves, respectively, which represents five phyla, ten classes, nineteen orders, and twenty-six families (six arachnids, three springtails, two diplurans, three millipedes, six insects, three terrestrial snails, one flatworm, five crustaceans, and two vertebrates, respectively). The Crystal-Wonder Cave System is the type locality for six species—Anillinus longiceps, Pseudanophthalmus humeralis, P. intermedius, Ptomaphagus hatchi, Tolus appalachius, and Chitrella archeri. The carabid beetle Anillinus longiceps is endemic to the Crystal-Wonder Cave System. Sixteen species are of conservation concern, including twelve taxa with NatureServe conservation ranks of G1–G3. The exceptional diversity of the Crystal-Wonder Cave System has been associated with several factors, including a high dispersal potential of cave fauna associated with expansive karst exposures along the Western Escarpment of the southern Cumberland Plateau, a high surface productivity, and a favorable climate throughout the Pleistocene. Full article

The Água Clara Cave System (ACCS) in Brazil is the richest hotspot of subterranean biodiversity in South America. In this study, we present an updated list of cave-restricted species in the ACCS and compare it with previously published hotspots in Brazil. Our list of cave-obligate fauna comprises 31 species, including 23 troglobionts and 8 stygobionts. The exceptional diversity of the ACCS can be attributed to factors related to the high dispersal potential of cave fauna within the system, high surface productivity, and the large size of the cave system size. Notably, we observed highly troglomorphic species in the ACCS, some of which are the most troglomorphic species in their respective groups in Brazil. The huge volume of galleries, high humidity, and trophic conditions prevailing in the ACCS may have played a role in shaping the strong troglomorphic traits observed in these species. However, all the obligate cave species in the ACCS require conservation attention and are at an elevated risk of extinction due to their limited ranges, few occurrences, and many potential threats. This study sheds light on the biodiversity and conservation status of cave-restricted fauna in the ACCS and highlights the importance of protecting these unique ecosystems. Full article