Occurrence of Cladocera (Crustacea) in subterranean waters in Yugoslavia

Contrary to some localities in France and Spain, Cladocera occur in hypogean waters in Yugoslavia very sporadically. Beside the stygobitic species, Alona hercegovinae from caves and Alona smirnovi from interstitial waters, particularly some other Chydoridae seem to be suited for hypogean life. Chydorus sphaericus, reputed as one of the most euryoecious cladocerans, occurs also the deepest in interstitial waters as well as in caves. Other species, found in hypogean waters are Simocephalus vetulus, Ilyocryptus sordidus, Eurycercus lamellatus, Chydorus ovalis, Leydigia leydigi, Acroperus harpae and Biapertura affnis.     

Habitat specificity of littoral Chydoridae (Crustacea,Branchiopoda, Anomopoda) in Plastic Lake,Ontario, Canada

This study identified two scales of pattern in the assemblages of Chydoridae (Crustacea, Branchiopoda, Anomopoda) in the shallow (<2 m) littoral zone of Plastic Lake, Ontario, Canada in the autumn of 1987. Twenty chydorid species were collected in 15 over-night sets of funnel traps in each of four habitat types. Analysis of variance multivariate analysis of variance, and discriminant function analysis revealed that assemblages differed among the habitats. Alona intermedia, Alona quadrangularis and Chydorus bicornutus were particularly abundant in the most structurally diverse habitat type – muddy, rock-strewn areas with approximately 40% bottom cover by the pipewort, Eriocaulon septangulare. In contrast, Anchistropus cf. minor was caught most often on bare shelves of rock. A second set of analyses demonstrated that chydorid assemblages also differed at a smaller scale, i.e. with local patchiness in bottom cover by the dominant macrophyte (E. septangulare). The abundance of Alona affinis was positively correlated with cover by E. septangulare, whereas Anchistropus cf. minor was caught mainly in microhabitats without vegetation. Alona intermedia and A. quadrangularis were most abundant in microhabitats with intermediate amounts of vegetation, suggesting their abundance is influenced by habitat factors other than vegetation.     

Cladocera (Crustacea) from Nicaragua

Thirty-one Cladocera taxa are recorded from lakes, rivers and ponds of Western Nicaragua. They include Alona bromelicola sp. nov. found in water accumulations in epiphytic Bromeliads. The Cladocera recorded are neotropical and circumtropical. Other invertebrates found are also listed.     

Fossil remains of an unknown Alona species (Chydoridae, Aloninae) from a high arctic lake in Nordaustlandet (Svalbard) in relation to glaciation and Holocene environmental history

We analyzed a lacustrine sediment core covering the Holocene from Lake Einstaken, Nordaustlandet, for its fossil Cladocera (Crustacea) with an aim to reconstruct past aquatic communities in this environmentally extreme and unexplored region. In the analysis, we encountered remains (carapaces, ephippia, headshields, and postabdomens) of an unknown chydorid (Chydoridae, Aloninae) species during two separate periods in the early Holocene. The remains had some comparable morphological characters with the European Alona guttata s.str. Sars, 1862 and with the glacial relict Alona werestschagini Sinev, 1999, but they differed clearly from the previous species; the headshield had broadly rounded rostrum and narrow fornices, the ephippium was heavily pigmented and reticulated, and the postabdomen had convex dorsal and ventral margins. The postabdomen had evidently similar morphology with Alona bergi R?en, 1992, which has been described, although inadequately, from arctic Canada and northern Greenland. We conclude, based on the morphology of the postabdomen, that the unknown remains belong to species closely resembling A. bergi, named here Alona cf. bergi, and assume that the species, whether the true A. bergi or some other cryptic species of the A. guttata group, is a postglacial relict of the high arctic adapted to cold climate. Herewith, we emphasize the need for extensive biogeographical investigations into both fossil and intact specimens of chydorids in the arctic.     

The population dynamics of Chydoridae and Macrothricidae (Cladocera: Crustacea) from the River Thames, U.K.

SUMMARY.

• 1 A study was made of the population dynamics of benthic cladocerans in the River Thames, U.K. These included three species of Chydoridae (Alona affinis Leydig, Disparalona rostrata (Koch 1841) and Leydigia leydigi Schodler) and one species of Macrothricidae Iliocryptus sordidus (Lievan).
• 2 The pattern of chydorid abundance was similar to that found in many lakes: a midsummer peak followed by a sharp decrease in numbers and subsequent low abundance. This was caused by a temporary decrease in natality, possibly due to food limitation, and a more permanent increase in mortality, thought to be due to predation.
• 3 Iliocryptus sordidus differed considerably from the chydorids, the major population peak occurring in the autumn. The lifestyle and adult size of Iliocryptus sordidus (Lievan) must render adults less vulnerable to invertebrate and fish fry predation.
• 4 A literature survey showed that the assemblage of species found in the unvegetated littoral of lakes and rivers included a taxocene of cladocerans.

     

Postembryonal development of male and abnormal sexual individuals of Alona affinis (Leydig, 1860) (Anomopoda,Chydoridae)

As in most other Chydoridae, Alona affinis has two juvenile instars in both sexes and development of the male is similar to that of previously studied species. Several interesting traits were found in the development of the first trunk limb. Males with abnormal morphology in sex-linked characters and ephippial females with a postabdomen similar to that of the adult male are described.     

The Occurrence of Fungi in the Recently Discovered Jarkowicka Cave in the Karkonosze Mts. (Poland)

Our study is one of the very few cases of speleomycological research in recently discovered caves. The aim of this research was to assess the population size of fungal colonies and their species composition in the Jarkowicka cave, discovered in 2012. The air samples were taken from one location outside the cave and from two locations inside of it. Mycological evaluation of the rocks inside the cave was performed usingswab sampling procedure. In the Jarkowicka cave we found 22 species of fungi, including 13 isolated from air at the entrance and from the walls, and 8 species from air inside the cave. Cladosporium spp. were the fungi most frequently isolated from internal atmosphere of the Jarkowicka cave, and from the external air. On the other hand, the fungi most frequently isolated from the rocks were Mucor spp. We found several species not yet described as cave inhabitants: Hypocrea pachybasioides, Cladosporium uredinicola, and Embellisia abundans. Our study may provide a basis for comparison to other similar studies conducted in frequently visited caves by tourists.     

Long-term changes in benthic Cladocera populations in Lake Myvatn, Iceland

Benthic Cladocera were monitored at five sites in Lake Myvatn, Iceland, over a decade (1990–1999), as part of a programme documenting the population fluctuations of animals at different trophic levels in the lake. The species composition remained relatively stable over the first seven years, but in 1997 the population of Eurycercus lamellatus was greatly reduced at all sites. The following year saw a mass occurrence of Alona rectangula and Alonella nana that were previously abundant only locally and rare at most sites. Alona affinis, A. quadrangularis, Acroperus harpae and Chydorus sphaericus were not affected. In 1999 the Cladocera assemblages returned to the pre-1997 situation. The shift was from large-bodied epibenthic and planktonic species (Eurycercus, Daphnia) to small infaunal (Alona rectangula) and ubiquitous (Alonella nana) species. Medium sized (Alona, Acroperus) and some small cladocerans (Chydorus) were not affected. The course of events was reminiscent of a trophic cascade caused by a change in size-selective predation pressure. If so, the impact of a predatory fish population (three-spined stickleback, Gasterosteus aculeatus) depended on whether cyclic chironomid populations were in a high or a low phase. The change in the Cladocera coincided with profound changes in the sediment characteristics associated with low chironomid abundance. We suggest that the relative competitive ability of the Cladocera species is reversed when the sediment has become homogeneous and nutrient-poor after overexploitation by the dominant, tube building and detritivorous chironomid Tanytarsus gracilentus.     

Ammonia oxidation (amoA) and nitrogen fixation (nifH) genes along metasandstone and limestone caves of Brazil

Abstract

Many cave-dwelling microorganisms have been studied, but little is known about whether genes related to the nitrogen cycle are present in this environment, particularly in sandstone caves. The profiles of nitrogen fixation (nifH) and archaeal and bacterial ammonia oxidation (amoA) genes were analyzed along a cave of metasandstone and limestone lithologies. Using polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis and quantitative PCR to evaluate these genes, we analyzed the variations in the microorganisms and frequency of these genes along the caves. In both caves analyzed for nifH, different community profiles were observed, particularly in entrance samples. Quantitative PCR of the genes showed that samples from the entrance of the caves contained a larger number of copies of amoA. In addition, archaeal amoA was predominant compared to bacterial amoA. The present study demonstrated that the genes for nitrogen fixation and ammonia oxidation are present in both cave lithologies and that their frequency and the organisms present along the caves vary with factors such as the characteristics of the cave itself.     

The freshwater fauna of Macquarie Island, including a redescription of the endemic water-flea Daphnia gelida (Brady) (Anomopoda: Crustacea)

The freshwater invertebrate fauna (excluding the Protozoa) of Macquarie Island is collated. This includes two Platyhelminthes, two Gastrotricha, three Tardigrada, 41 rotifera, at least eight Nematoda, nine Annelida, and 21 Arthropoda. The latter comprises six species of Anomopoda, two Copepoda, two Ostracoda, an Isopoda, five Acarina, and at least five species of Insecta with aquatic or semi-aquatic larvae. The freshwater Anomopoda (Cladocera) of Macquarie Island are re-evaluated, six species are now recognized and the largest, identified as Daphnia gelida (Brady), is redescribed. The records of both Alona weinecki Studer and Pleuroxus macquariensis Frey are confirmed, while that of Macrothrix hirsuticornis Norman and Brady is accepted with some reservations. Alona quadrangularis (O.F. Müller) is re-instated and records of Chydorus sphaericus O.F. Müller ascribed to C. patagonicus Ekman.     

Cladocera response to Late Glacial to Early Holocene climate change in a South Carpathian mountain lake

This study explores changes in cladoceran composition in a high mountain lake of the Retezat (Lake Brazi), the South Carpathian Mountains of Romania, during the Late Glacial–Early Holocene (14,500–11,600 cal. yr. bp) transition using a paleolimnological approach. The lake had a species poor cladoceran community throughout this period. Daphnia longispina, Chydorus sphaericus and Alona affinis were the most common, showing marked fluctuations in their relative abundances through time. Distinct faunal response to warming at the Younger Dryas (YD)/Preboreal transition was recorded by increasing fossil densities and distinct community composition change: Alona affinis became dominant while numbers of Chydorus sphaericus dramatically decreased. In the Early Holocene, the productivity of Lake Brazi seem to have increased as reflected by higher numbers of Cladocera due to appearance of new species (Alona rectangula, A. quadrangularis and A. guttata) which are common in productive waters. Significant negative correlation was found between average dorsal length of daphnid ephippia and the NGRIP ^δ18O isotope values. Given the absence of fish predation, changes in Daphnia ephippia size were taken to indicate climatic change: larger ephippium size inferred cold conditions during the Late Glacial, while smaller size reflected climate warming during the Early Holocene. We conclude that Cladocera fossils are good indicators of climatic change that happened during the transition from the Late Glacial to the Holocene. We found that climatic conditions can be tracked either by size distribution of Daphnia ephippia (larger ephippium size under colder climate) and/or by community change of cladocerans.     

Evolution of cave living in Hawaiian Schrankia (Lepidoptera: Noctuidae) with description of a remarkable new cave species

Although temperate cave‐adapted fauna may evolve as a result of climatic change, tropical cave dwellers probably colonize caves through adaptive shifts to exploit new resources. The founding populations may have traits that make colonization of underground spaces even more likely. To investigate the process of cave adaptation and the number of times that flightlessness has evolved in a group of reportedly flightless Hawaiian cave moths, we tested the flight ability of 54 Schrankia individuals from seven caves on two islands. Several caves on one island were sampled because separate caves could have been colonized by underground connections after flightlessness had already evolved. A phylogeny based on approximately 1500 bp of mtDNA and nDNA showed that Schrankia howarthi sp. nov. invaded caves on two islands, Maui and Hawaii. Cave‐adapted adults are not consistently flightless but instead are polymorphic for flight ability. Although the new species appears well suited to underground living, some individuals were found living above ground as well. These individuals, which are capable of flight, suggest that this normally cave‐limited species is able to colonize other, geographically separated caves via above‐ground dispersal. This is the first example of an apparently cave‐adapted species that occurs in caves on two separate Hawaiian islands. A revision of the other Hawaiian Schrankia is presented, revealing that Schrankia simplex, Schrankia oxygramma, Schrankia sarothrura, and Schrankia arrhecta are all junior synonyms of Schrankia altivolans. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 156 , 114–139.     

Intra-lake heterogeneity of sedimentary cladoceran (Crustacea) assemblages forced by local hydrology

Intra-lake variation of fossil Cladocera (Crustacea) assemblages in 31 surface sediment samples in Lake Pieni-Kauro and River Saavanjoki, eastern Finland, was examined with an objective to identify habitat specificity of Cladocera in relation to local hydrology-related environmental factors. The surface sediment assemblages showed high levels of heterogeneity, mainly as to water depth and lentic–lotic gradients in the lake–river complex. This was evident from the principal component analysis which indicated a major trend from shallow to deep samples and a secondary trend from lentic to lotic samples, and from redundancy analysis (RDA), which recognized water depth and river flow as the most important environmental variables in explaining cladoceran variability within the dataset. According to the RDA and generalized linear models, Daphnia spp., Bosmina (Eubosmina), and Alona quadrangularis showed association with deep water localities, whereas Bosmina longirostris and Alona affinis preferred littoral habitats. Acroperus harpae and Chydorus sphaericus s.l. appeared to favor lotic habitats. The results propose that littoral taxa are primarily deposited postmortem or after molting close to their shallow water habitats, while planktonic cladocerans accumulate principally in deepwater locations. Accordingly, it appears that in heterogeneous basins intra-lake surface sediment samples integrate locally living fauna that is driven by local hydrology-related factors, such as water depth, sediment properties, macrophytes, and river flow and coupling biotic interactions.     

Cladoceran assemblages in a mineralization gradient

Cladoceran assemblages were studied in littoral samples from 44 water bodies in Central Spain, showing great differences in salinity and permanence of water. Principal component analyses (PCA) were performed with data on cladoceran relative abundances to identify the main groups of species. Five main groups of species were found, defining the following types of environments: (I) Small but deep hard water lakes (II) permanent but shallow hard water lakes fed by surface springs, rich in macrophytes (III) ephemeral and shallow soft waters lakes (IV) subsaline and hyposaline lakes in their lower range, specially the permanent ones and (V) saline lakes (salinities>6 mg l^–1) subject to short or long periods of dryness. The main species constituting these groups were: Group (I): Acroperus neglectus, Alona guttata, Pleuroxus truncatus, Daphnia longispina; group II: Phrixura leei, Latonura rectirostris, Eurycercus lamellatus; Alonella excisa, Daphnia pulicaria; group III: Ephemeroporus phintonicus, Macrothrix rosea, Moina micrura; group IV: Alona rectangula, Ceriodaphnia reticulata, Tetrocephala ambigua, Diaphanosoma mongolianum; group V: Alona salina, Pleuroxus letourneuxi, Dunhevedia crassa, Moina brachiata, Daphnia magna and Daphnia mediterranea. Sample scores from PCA extracted from the correlation matrix of cladoceran proportions were correlated with limnological measurements. Significant correlations with salinity, alkalinity anions and cations indicate that salinity is an important factor in the distribution of the species. However, species assemblages also reflect other factors, such as temporality and littoral development.     

Some littoral anomopods (Crustacea) from Central Amazonia

Samples collected in Central Amazonia contained 16 species of Chydoridae, 4 species of Macrothricidae and 1 species of Ilyocryptidae. A new chydorid,Celsinotum laticaudatum sp. nov. is described, clearly differing from Australian species of this genus. Variation ofAlona dentifera (Sars, 1901) is commented upon, as well as a peculiar specimen ofAlona.     

Distribution and phylogenetic relationships of Australian glow-worms Arachnocampa (Diptera, Keroplatidae)

Glow-worms are bioluminescent fly larvae (Order Diptera, genus Arachnocampa) found only in Australia and New Zealand. Their core habitat is rainforest gullies and wet caves. Eight species are present in Australia; five of them have been recently described. The geographic distribution of species in Australia encompasses the montane regions of the eastern Australian coastline from the Wet Tropics region of northern Queensland to the cool temperate and montane rainforests of southern Australia and Tasmania. Phylogenetic trees based upon partial sequences of the mitochondrial genes cytochrome oxidase II and 16S mtDNA show that populations tend to be clustered into allopatric geographic groups showing overall concordance with the known species distributions. The deepest division is between the cool-adapted southern subgenus, Lucifera, and the more widespread subgenus, Campara. Lucifera comprises the sister groups, A. tasmaniensis, from Tasmania and the newly described species, A. buffaloensis, found in a high-altitude cave at Mt Buffalo in the Australian Alps in Victoria. The remaining Australian glow-worms in subgenus Campara are distributed in a swathe of geographic clusters that extend from the Wet Tropics in northern Queensland to the temperate forests of southern Victoria. Samples from caves and rainforests within any one geographic location tended to cluster together within a clade. We suggest that the morphological differences between hypogean (cave) and epigean (surface) glow-worm larvae are facultative adaptations to local microclimatic conditions rather than due to the presence of cryptic species in caves.     

A new cavernicolous, semiaquatic species of Serradium (Diplopoda, Polydesmidae) and its terrestrial, sympatric congener. With notes on the genus Serradium

Serradium semiaquaticum sp. n. is described from several North Italian caves. The new species is very similar to, and probably the closest relative of S. hirsutipes Verhoeff, 1941, which lives in the same caves as S. semiaquaticum but has a wider distribution. Serradium hirsutipes is redescribed and newly recorded from several caves. Serradium semiaquaticum is remarkable by its semiaquatic habits and correspondingly modified spiracles and mouthparts, whereas S. hirsutipes is normal in these respects. The genus Serradium is reviewed, and a key to the known species is given. Serradium as currently defined may not be a monophyletic group. Serradium semiaquaticum and S. hirsutipes show strong gonopodal similarity (synapomorphy?) with species of Polydesmus, subgenus Acanthotarsius.     

Chaenorhinum semispeluncarum sp. nov. and C. yildirimlii sp. nov. (Scrophulariaceae) from east Anatolia,Turkey

Chaenorhinum semispeluncarum H. Y?ld?r?m, Kit Tan, S. ?enol & A. Pirhan sp. nov. and C. yildirimlii Kit Tan, H. Y?ld?r?m, S. ?enol & A. Pirhan sp. nov. (Scrophulariaceae, C. sect. Microrrhinum) from east Anatolia are described and illustrated. They are both narrow endemics related to the rare C. cryptarum, also from east Anatolia. Chaenorhinum semispeluncarum occurs on calcareous marl rich in potassium nitrate at the entrance of wet caves in Malatya and differs from C. cryptarum by its erect habit, smaller corollas, shallowly ribbed and tuberculate, bicoloured seeds. Chaenorhinum yildirimlii from the neighbouring province of Erzincan was found on alluvial soil of stream banks and differs from C. semispeluncarum by its seed characters which are similar to those of C. cryptarum. Chaenorhinum yildirimlii differs from C. cryptarum, most conspicuously by the violet lower corolla lip spotted dark purple at the apex.