Troglomorphic Sculpins of the Cottus Carolinae Species Group in Perry County, Missouri: Distribution, External Morphology, and Conservation Status

The existence of cavernicolous sculpin (here allocated to Cottus carolinae, banded sculpin, and referred to as grotto sculpin), in the karst regions of Perry County, Missouri, first came to our attention in 1991. Examination of 35 caves in Missouri, 96 in Illinois, 17 in Tennessee, two in Indiana, and 11 in Arkansas revealed that banded sculpin are common in cave habitats; however, grotto sculpin are limited to two karst areas of Perry County, Missouri, where they are known from only six cave systems. These caves and their streams are extensive and apparently provide a unique habitat compared to other karst systems; this may be a critical factor in the present restricted distribution of the grotto sculpin. Grotto sculpin occupy pools and riffles of cave streams, and occur over a variety of substrates, from sediment to breakdown. Density estimates in Mystery and Running Bull caves were 0.29 and 0.63 individuals m^-2, respectively. Grotto sculpin have small eyes (1–6% SL vs. 6–10% SL in epigean samples), significantly reduced pigmentation (including nearly complete loss of dorsal saddles), a reduction in pelvic fin ray number (from 4+4 elements to often 4+3 , or 3+3), and enlarged cephalic lateralis pores (e.g., mandibular pores of cavernicolous samples are 2–3 times those of epigean stream samples). Multivariate analyses of body shape revealed statistically significant separation of epigean and hypogean samples, with eye size highly variable, but smallest in the Running Bull Cave population. We interpret these results as representative of losses associated with long-term cave habitation. Caves of Perry County provide ample habitat for grotto sculpin, but because the caves are located downgradient of the city of Perryville and an intensively farmed landscape, point and non-point source pollution threaten their continued existence. Escape of farm-pond fishes through the extensive sinkhole network in Perry County has increased potential predation pressure on grotto sculpin by channel catfish, Ictalurus punctatus, and other species normally excluded from cave environments.     

Sampling adequacy in an extreme environment: species richness patterns in Slovenian caves

Caves harbor a rich fauna unique to subterranean environments. Although extensive records of cave animals are available, only a small fraction of known caves in any region have been biologically assessed. We investigated the impact of incomplete sampling using one of the richest, best documented cave faunas in the world – that of the Dinaric karst of Slovenia. We utilized time snapshots (1940, 1970, and 2000) of the caves and cave fauna to analyze stability of hotspots, spatial pattern, and relationship between number of species and number of caves. Using data aggregated into 100km² hexagons, the location of hotspots, black–white joins, Moran's I, and spatial autocorrelation all remained constant, at least from 1970 on. The linear regression coefficient of the relationship between number of caves and number of species declined with time. Most hexagons had been sampled, but there was no indication that any hexagon had been sampled intensively enough for the accumulation curve of number of caves versus number of species within a hexagon to reach an asymptote. This appeared to be the result of a highly skewed distribution of species richness among caves. Number and position of hotspots can be predicted from information on these few high diversity caves.     

Neolithic bats from Dowel Cave, Derbyshire

If the post-glacial history of British mammals is poorly documented (Yalden, 1982), then that of the bats is particularly poorly understood. Yet the history of the bat fauna is potentially very interesting; woodland species such as Myotis bechsteini and Plecotus spp. should have been much more numerous when woodland was more extensive, and various southern species such as P. austriacus and Rhinolophus ferrumequinum might have spread further north in warmer periods. In Poland, Woloszyn (1970) has documented numerous cave faunas, probably of Neolithic age, in which M. bechsteini was indeed very numerous (it is now as rare in Poland as in Britain). Myotis bechsteini is also reputed to be numerous in the Neolithic flint mines of Grimes Graves, Norfolk (Clarke, 1963), though no details of numbers seem to have been published.     

贵州毕节发现古人类化石与哺乳动物群

2008年12月在贵州毕节团结乡首次发现麻窝口洞化石点,经2009年、2012年和2013年3次发掘,在麻窝口洞上部砂质黏土地层中共发现了四千余件哺乳动物牙齿化石。2013年7月发现的3枚古人类牙齿,分别为左上犬齿、左上第一臼齿和右上第二臼齿。人类牙齿尺寸偏小,臼齿咬合面沟纹简单,没有复杂的咬合面皱纹和附尖齿带结构,牙根短而不显粗壮,上述特点有别于我国已经发现的直立人和早期智人,可归入解剖学上的现代人。与人类相伴的哺乳动物化石,经初步鉴定共计8目20科43属53种,动物群组合反映出亚热带森林生态环境。根据动物群的时代特点,地貌地层及堆积物的光释光年代测定,指示毕节麻窝口洞古人类的时代可能为中更新世晚期,或者晚更新世早期,毕节古人类牙齿的发现为东亚地区现代人的起源及演化增添了新的证据。     

Decrease in allochthonous organic inputs in dark submarine caves,connection with lowering in benthic community richness

Ten sediment trap arrays were deployed over two years for periods of 3 to 40 days in three different sampling points along a 50 m long Mediterranean submarine cave. Mean total particulate matter flux decreased strongly from the semi-dark area (3.3 g m^–2 d^–1) to the dark area (0.8 and 0.6 g m^–2 d^–1). Carbon represented 3.3% to 3.5% and nitrogen 0.34% to 0.38% of settling dry matter. The decrease in organic input from the entrance to the terminal part of the cave results in increasingly oligotrophic conditions with distance from the cave entrance. Horizontal resource limitation can be connected with a strong zonal decrease in fauna richness. Biomass declines both in hard substrate and soft bottom communities. Despite major differences, some similarities are noticed between oligotrophic conditions that may occur in the dark cave and those in around 1000 m depth ecosystems. Dark oligotrophic submarine caves can be considered to be good scale models for the study of some aspects of general trophic pathways.     

Epigean and subterranean ichthyofauna from the São Domingos karst area, Upper Tocantins River basin, Central Brazil

In a survey of epigean and cave streams in the São Domingos karst area, 38 species were present in the stream reaches, including 10 characiforms, 19 siluriforms, seven gymnotiforms and two perciforms. One species of Astyanax and the new armoured catfish species Parotocinclus were the most common epigean fishes in São Domingos. The most conspicuous non-troglomorphic cave fishes were Hoplerythrinus unitaeniatus , Astyanax sp., Brycon sp. and two species of Imparfinis , with I. hollandi being the most common fish in most caves. São Domingos karst area has the most diverse and abundant Brazilian cavefish fauna, not only in terms of troglobitic species but also in general fish richness, with 22 non-troglomorphic species recorded in caves in addition to five troglobitic ones. Most fishes examined for stomach contents had at least partially full stomachs. The studied fishes were carnivorous, feeding primarily on aquatic insects. Fishes with developed gonads recorded in caves were I. hollandi , Rhamdia quelen , Pseudocetopsis plumbeus , Hoplerythrinus unitaeniatus and Cichlasoma araguaiensis , indicating a potential for reproduction in the subterranean habitat.     

Can wing morphology inform conservation priorities for Southeast Asian cave bats?

Adaptations for foraging in the complex airspaces of forest interiors may make bat species in the Asian tropics particularly susceptible to forest loss. However, ecomorphological analysis of Vietnamese bat assemblages challenges the hypothesis that, due to their greater vagility, cave‐roosting bats are less vulnerable to habitat fragmentation than foliage‐roosting species. Of the 13 most highly adapted forest‐interior species in our study, eight were cave‐roosting members of the Rhinolophidae and Hipposideridae and had wing morphologies closely resembling five foliage‐roosting members of the Murininae and Kerivoulinae—species typically thought to have low vagility. Overall, both cave‐roosting and foliage‐roosting bats exhibited a wide range of flight indices and species' wing designs corresponded with preferred foraging habitats, suggesting that foraging strategy may outweigh roost preference as a determinant of bat wing morphology and flight performance. Consequently, where such variation occurs, cave‐roosting bat ensembles are likely to include species with low vagility and similar sensitivity to habitat fragmentation. This could have important conservation implications as Asian karst formations support high cave densities and important bat diversity yet increasingly represent forest refugia in anthropogenic landscapes. We, therefore, advocate greater consideration of species vagility in determining conservation priorities for the region's bat fauna.     

安徽东至华龙洞古人类遗址哺乳动物化石的初步研究

华龙洞遗址发现于2004年,先后于2006和2014～2017年进行了5次发掘,期间发现了若干古人类化石和大量哺乳动物化石;本文是对2014～2016年出土哺乳动物化石的初步研究成果。目前已鉴定出8目24科43种(含未定种)哺乳动物,其中以偶蹄类化石最丰富。化石保存状况较差,以碎骨为主,牙齿较少,完整骨骼更少;但骨骼上鲜见啮齿类啮咬痕迹。华龙洞动物群与南京汤山猿人遗址、和县猿人遗址及重庆盐井沟等动物群较为相似,尤其是与和县猿人遗址及南京猿人遗址动物群最为接近,主要表现在如下方面:1)都含古人类化石;2)都不含第三纪动物群的孑遗分子;3)都含有大熊猫-剑齿象动物群的主要成员(大熊猫、剑齿象、巨貘及猪獾等),同时也都含一定量的北方属种,但华龙洞含北方成分相对较少,只发现翁氏麝鼩、麝鼹、变异仓鼠、布氏毛足田鼠、棕熊、李氏野猪、葛氏斑鹿及大角鹿等,华龙洞的大角鹿是该属分布最靠南的地点;4)都含有剑齿象而不含晚更新世常见的亚洲象;5)都含有大量头后骨骼,与以含单个牙齿为主的其它南方洞穴迥然有别。从化石保存状况及属种组成判断,华龙洞堆积时代与和县猿人遗址最为接近,也是中更新世。由于遗址尚未完全暴露,其堆积性质尚不清楚;但从蝙蝠类化石判断,很可能与洞穴堆积有关。     

贵州荔波玉屏洞穴陆生动物食物来源及营养级

洞穴是“极端地下生物多样性”的聚集地, 为了揭示洞穴陆生动物的食物来源以及营养级关系, 本文于2016年10月对贵州荔波玉屏镇的3个代表性洞穴内的陆生动物进行调查, 应用¹³C和¹⁵N稳定同位素方法, 分析了洞内陆生动物和基础碳源的δ¹³C、δ¹⁵N值变化特征, 探究了各动物类群的营养级位置以及不同的基础碳源对动物的食物源的贡献率。结果表明: 洞穴植物的δ¹³C值范围为-38.25‰ ± 0.95‰至-29.44‰ ± 0.49‰, 土壤有机质δ¹³C值范围为-32.73‰ ± 0.03‰至-24.68‰ ± 0.41‰, 大部分不在洞穴植物的δ¹³C变化范围内。洞穴动物δ¹³C、δ¹⁵N值范围分别为-34.22‰ ± 0.39‰至-14.83‰ ± 0.78‰、1.86‰ ± 0.20‰至16.43‰ ± 0.05‰, 表现出较大的种(或类群)间差异。IsoSource软件估算结果表明, 洞穴土壤有机质对78.3%动物类群的食物源的贡献率高于植物。荔波玉屏洞穴消费者的营养级范围为1.01-5.32, 其中, 巨蚓科、螺类、潮虫科、马陆、大蚊科、夜蛾科主要处于第2营养层次; 蚰蜒科、蚁蛉科(幼虫)、蝙蝠处于第3营养层次; 蜚蠊科处于第2-3营养层次; 驼螽科、蠼螋科处于第2-4营养层次; 蜘蛛处于第2-5营养层次, 跨3个营养级。综上认为, 洞穴土壤有机质是洞穴消费者的主要食物基础。大部分同一类群的动物在洞穴中所处的营养级位置较稳定, 少部分同属于一个类群的动物在不同洞穴或同一洞穴不同光带所处的营养级位置有差异。     

Cave adaptation in the spider genus Anthrobia (Araneae, Linyphiidae, Erigoninae)

The genus Anthrobia Tellkampf, 1844 is revised and expanded to include two epigean species, Anthrobia acuminata ( Emerton, 1913 ) comb. nov., and A. whiteleyae sp. nov., and two troglobites, the type species A. monmouthia Tellkampf, 1844 , and A. coylei sp. nov. The female of A. acuminata is described for the first time. All four Anthrobia species were added to a phylogenetic analysis of erigonine genera. Analysis of this matrix results in a single most parsimonious tree (length = 915, CI = 0.23, RI = 0.58; uninformative characters excluded: length = 911, CI = 0.23), which places Anthrobia sister to Diplocentria Hull, 1911. Troglobitic Anthrobia and epigean Anthrobia are both monophyletic. In comparison to the epigean species, troglobitic Anthrobia exhibit the following putative adaptations to cave life: loss of eyes, elongation of the legs, and reduction of the tracheal system. The reliability of phylogenetic results indicating monophyly of cave Anthrobia are discussed in light of the fact that potentially cave adaptive synapomorphies support this relationship.     

Bubble-Induced Cave Collapse

Conventional wisdom among cave divers is that submerged caves in aquifers, such as in Florida or the Yucatan, are unstable due to their ever-growing size from limestone dissolution in water. Cave divers occasionally noted partial cave collapses occurring while they were in the cave, attributing this to their unintentional (and frowned upon) physical contact with the cave walls or the aforementioned “natural” instability of the cave. Here, we suggest that these cave collapses do not necessarily result from cave instability or contacts with walls, but rather from divers bubbles rising to the ceiling and reducing the buoyancy acting on isolated ceiling rocks. Using familiar theories for the strength of flat and arched (un-cracked) beams, we first show that the flat ceiling of a submerged limestone cave can have a horizontal expanse of 63 meters. This is much broader than that of most submerged Florida caves (~ 10 m). Similarly, we show that an arched cave roof can have a still larger expanse of 240 meters, again implying that Florida caves are structurally stable. Using familiar bubble dynamics, fluid dynamics of bubble-induced flows, and accustomed diving practices, we show that a group of 1-3 divers submerged below a loosely connected ceiling rock will quickly trigger it to fall causing a “collapse”. We then present a set of qualitative laboratory experiments illustrating such a collapse in a circular laboratory cave (i.e., a cave with a circular cross section), with concave and convex ceilings. In these experiments, a metal ball represented the rock (attached to the cave ceiling with a magnet), and the bubbles were produced using a syringe located at the cave floor.     

Population Biology and Growth of Ozark Cavefish in Logan Cave National Wildlife Refuge, Arkansas

Ozark cavefish, Amblyopsis rosae, is a threatened species endemic to the Springfield Plateau of the Ozark Highlands in Arkansas, Missouri, and Oklahoma. One of the largest known Ozark cavefish populations, located in Logan Cave, Arkansas, was surveyed 25 times over a two-year period between 1993 and 1995. During the study, 147 Ozark cavefish > 30 mm (TL) were marked with visual implant tags and 140 Ozark cavefish were available for recapture; 68 were recaptured 189 times and the rest (72) were never recaptured. Individual Ozark cavefish persisted in Logan Cave for a relatively short time. Only 14% of 80 fish tagged during a previous study in 1992 were recaptured during this study, and half of all recaptured fish disappeared within three months. However, if a fish persisted for at least seven months in the cave, its probability of being recaptured over an additional year was high. Maximum persistence of a tagged fish was 28 months, suggesting these fish have a maximum life-span of 4–5 years. Growth averaged 0.6 mm per month, with maximum recorded growth of 6 mm per month and a maximum size of 65 mm TL. Smaller fish grew faster than larger fish but growth rates were sporadic, with several mid-sized fish (45–49 mm) showing little growth (0–3 mm year^-1) while some fish > 50 mm grew up to 12 mm year^-1. Most fish gained in length during April–October, the same period a maternity colony of gray bats occupied the cave. Gross Ozark cavefish movement over the study period ranged up to 1002 m, with a mean movement of 1.2 m day^-1; movement was positively correlated with Ozark cavefish total length. Death seemed the most likely explanation for loss of tagged Ozark cavefish, including fish that emigrated out of the cave. Little up-stream movement was recorded between reaches and did not account for loss of tagged fish. Reproduction within the cave and immigration from the aquifer accounted for persistence of Ozark cavefish in Logan Cave.     

Milyeringa Veritas (Eleotridae), a remarkably versatile Cave Fish from the Arid Tropics of Northwestern Australia

The blind cave gudgeon Milyeringa veritas is restricted to groundwaters of Cape Range and Barrow Island, northwestern Australia. It occurs in freshwater caves and in seawater in anchialine systems. It is associated with the only other stygobitic cave vertebrate in Australia, the blind cave eel, Ophisternon candidum, the world's longest cave fish, and a diverse stygofauna comprising lineages with tethyan tracks and widely disjunct distributions, often from North Atlantic caves. The cave gudgeon inhabits a karst wetland developed in Miocene limestones in an arid area. There is an almost complete lack of information on the basic biology of this cave fish, despite it being listed as threatened under the Western Australian Wildlife Conservation Act. Allozyme frequencies and distributions indicate significant population sub-structuring on the Cape Range peninsula such that the populations are essentially isolated genetically suggesting that more than one biological species is present. Further, they suggest that the vicariant events may have been associated with a series of eustatic low sealevels. Analysis of intestinal contents indicates that they are opportunistic feeders, preying on stygofauna and accidentals trapped in the water, at least at the sites sampled which were open to the surface, a conclusion supported by the results of stable isotope ratio analysis. The gudgeons are found in freshwater caves and throughout deep anchialine systems in which they occur in vertically stratified water columns in which there is a polymodal distribution of water chemistries (temperature, pH, salinity, dissolved oxygen, redox, dissolved inorganic nitrogen series, hydrogen sulphide).     

Metagenomic Analysis from the Interior of a Speleothem in Tjuv-Ante's Cave,Northern Sweden

Speleothems are secondary mineral deposits normally formed by water supersaturated with calcium carbonate percolating into underground caves, and are often associated with low-nutrient and mostly non-phototrophic conditions. Tjuv-Ante’s cave is a shallow-depth cave formed by the action of waves, with granite and dolerite as major components, and opal-A and calcite as part of the speleothems, making it a rare kind of cave. We generated two DNA shotgun sequencing metagenomic datasets from the interior of a speleothem from Tjuv-Ante’s cave representing areas of old and relatively recent speleothem formation. We used these datasets to perform i) an evaluation of the use of these speleothems as past biodiversity archives, ii) functional and taxonomic profiling of the speleothem’s different formation periods, and iii) taxonomic comparison of the metagenomic results to previous microscopic analyses from a nearby speleothem of the same cave. Our analyses confirm the abundance of Actinobacteria and fungi as previously reported by microscopic analyses on this cave, however we also discovered a larger biodiversity. Interestingly, we identified photosynthetic genes, as well as genes related to iron and sulphur metabolism, suggesting the presence of chemoautotrophs. Furthermore, we identified taxa and functions related to biomineralization. However, we could not confidently establish the use of this type of speleothems as biological paleoarchives due to the potential leaching from the outside of the cave and the DNA damage that we propose has been caused by the fungal chemical etching.     

Regional species richness in an obligate subterranean dwelling fauna – epikarst copepods

Aim  The diversity of the obligate cave-dwelling fauna has proved difficult to measure because of the highly localized distributions of most species. We investigated: (1) the local and regional diversity patterns of a major component of the obligate cave-dwelling fauna living in the epikarst zone, the karst layer closest to the surface; (2) variations in local and regional patterns of species richness; and (3) sampling sufficiency at multiple scales.
Location  Caves in the Dinaric Mountains of Slovenia.
Methods  We sampled continuously the abundance of 37 species of copepods dislodged from the epikarst from 35 ceiling drips in six caves for a period of one year. Copepods were collected in a specially designed net that allowed continuous collection.
Results  Based on species accumulation curves and Chao estimates of total diversity, we determined that 3–4 months of continuous sampling were sufficient to find 90% of the species in a drip, that five drips were sufficient to find 90% of the species in a cave, and that five caves were sufficient to find 90% of the species in a region.
Main conclusions  The epikarst copepod fauna is a significant part of the aquatic cave fauna, contributing about 20% at the regional level. Because of the scale of variation, much of which occurs within a cave, and because of the availability of continuous sampling devices, the epikarst component of subterranean diversity seems to be more thoroughly and accurately measured than do other components.     

Habitat and Population Data of Troglobitic Armored Cave Catfish, Ancistrus Cryptophthalmus Reis, 1987, from Central Brazil (Siluriformes: Loricariidae)

Population ecology of the troglobitic armored catfish, A. cryptophthalmus, from caves in São Domingos karst area of central Brazil, was studied in a two-census capture-mark-recapture study carried out during the dry season of 1999. Like many loricariids, including epigean Ancistrus catfishes from that area, A. cryptophthalmus is a typical bottom-dweller with a strong preference for rocky substrates in fast-flowing stream sectors. Relatively high population densities, when compared to other cavefishes, were recorded in the studied cave sections: 0.9 individuals m^–2 in Angélica Cave and 0.5 individuals m^–2 in Passa Três Cave. Passa Três Stream is a small tributary of the São Vicente Cave system, and the estimated population for Passa Três Cave (ca. 2000 m long) is around 1000 individuals. On the other hand, the large Angélica Cave Stream (8 km long) harbors a very large population, conservatively estimated at 20 000 individuals. No fish movements of distances longer than 100 m were recorded in the 40-day period. In Passa Três Cave, a few movements of distances up to 60 m were detected. Proportion of mature females in Angélica Cave was higher than in Passa Três Cave, possibly reflecting a greater food availability in the first cave. Mean individual growth rates in Angélica Cave (1.35 mm month^–1 for size class <41 mm SL, 0.17 mm month^–1 for size class >41 mm SL) point to relatively high longevities, possibly attaining 15 years.     

Changes in the fish fauna of the Oosterschelde estuary — a ten-year time series of fyke catches

Frequency of occurrence of fish species was monitored on a fortnightly basis in four fykes and a weir in the Oosterschelde estuary from 1979 through 1988. This was done in order to record changes in the fish fauna that may have occurred as a response to the construction of a storm-surge barrier in the mouth of the Oosterschelde (1984–1986) and the concomitant building of compartmentalization dams in the landward part. These compartmentalization dams reduced the freshwater inflow into the system. Principal component analysis using the annual averages in frequency of occurrence suggests a slight shift occurred in the fish community separating a cluster of years 1979–1984 from the cluster 1985–1988. Many of the changes in individual species could be attributed to fluctuations in yearclass strength or were part of changes occurring on a wider geographical scale. The only impact of the construction works seems to be the decrease in a number of anadromous fish. Fish traps seem to be useful as a monitoring tool for a number of species. The value of the data collected could be improved if catch size and length-frequency data are recorded.     

A new genus and species for the first recorded cave-dwelling Cavernicola (Platyhelminthes) from South America

Species diversity of Brazilian cave fauna has been seriously underestimated. A karst area located in Felipe Guerra, northeastern Brazil, which is a hotspot of subterranean diversity in Brazil, has revealed more than 20 troglobitic species, most of them still undescribed. Based on recent samplings in this karst area, we document the occurrence of the suborder Cavernicola (Platyhelminthes) in South American hypogean environments for the first time and describe a new genus and species for this suborder. Hausera Leal-Zanchet & Souza, gen. n. has features concordant with those defined for the family Dimarcusidae. The new genus is characterized by two unique features, viz. an intestine extending dorsally to the brain and ovovitelline ducts located dorsally to the nerve cords, which is complemented by a combination of other characters. The type-specimens of Hausera hauseri Leal-Zanchet & Souza, sp. n. are typical stygobionts, unpigmented and eyeless, and they may constitute an oceanic relict as is the case of other stygobiotic invertebrates found in this karst area in northeastern Brazil.     

Mustelids from Sackdilling Cave (Bavaria,Germany) and their biostratigraphic significance

Sackdilling Cave is a karst fissure filled with a fossiliferous breccia including abundant fossil remains, mostly snails and small mammals. The taxonomic status of mustelid remains from this cave was previously regarded as controversial and, consequently, different authors listed different species from the locality. A detailed revision of the material shows the presence of five mustelid species: Meles sp., Martes vetus, Mustela strandi, Mustela palerminea, and Mustela praenivalis. Among them, especially noteworthy is the presence of the type specimen of Martes vetus. The Sackdilling holotype resembles Martes foina and differs from that of Martes martes in a short and broad viscerocranium; wide and less extended forward incisor row; compressed, short and wide temporal region; large, strongly inflated and convex tympanic bullae; and narrow P3 with weak lingual bulge. Some dental characters are specific for Martes vetus and show some intermediate values between Martes foina than Martes martes. Among them are the P4 protocone length and the M1 trigon length. The revised material from Sackdilling Cave of Mustela palerminea and Mustela praenivalis was compared with that from other Early and early Middle Pleistocene sites of Europe and showed the presence of intermediate characters. Subsequently, based on the entire mustelid assemblage and other faunal elements (mainly rodents), the age of this fauna was estimated as ca. 0.9–0.7 Ma.