Age and growth of Arno goby,Padogobius nigricans (Canestrini, 1867), in the Aggia River (Umbria,Central Italy)

In this study, data of Padogobius nigricans, a species endemic to Central Italy, were used to assess the age, growth parameters and condition of this species. Length–weight relationships are also provided and represent the first available reference in the literature for the Arno goby. Data were collected in the Aggia River, a tributary of the Tiber River, by monthly samplings. A total of 780 specimens ranging in size from 1.5 to 9.2 cm were analyzed. Age was assessed by examination of scales, with the maximum age of 4+  years observed in males and 3+ in females. Previous growth was determined by back‐calculation of scale measurements. The von Bertalanffy growth parameters were estimated separately for sexes (males: L_∞ = 9.759 cm, k = 0.505, t₀ = 0.025, Ф′ = 1.682; females: L_∞ = 8.989, k = 0.458, t₀ = 0.028; Ф′ = 1.599). Evidence of growth differences between sexes was found, with males living longer and reaching larger sizes. Using the relative condition factor, condition was lower in females than in males, especially during the breeding period due to the strain of high reproduction. Competition with the congeneric P. bonelli, a species endemic to Northern Italy that was introduced in Central Italy, seems not to have been disadvantaged directly by the growth of P. nigricans in the Aggia River, since no selective size‐mortality occurred in the population.     

Diet overlap and resource partitioning among three forage fish species in Coorong,the largest inverse estuary in Australia

Protracted drought in southern Australia has degraded the system function of the Coorong estuary and intensified resource competition among forage fish species. The present study investigates the gut content, prey composition and dietary overlap of three forage fishes: smallmouth hardyhead (Atherinosoma microstoma), Tamar River goby (Afurcagobius tamarensis) and sandy sprat (Hyperlophus vittatus) influenced by environmental variation in the Murray Estuary and Coorong. The prey species identified in fish stomachs were dominated by crustaceans (amphipods, ostracods and harpacticoids), but nematodes and acanthocephalans were also common in all forage fishes. The diet of the sandy sprat and Tamar River goby highly overlapped (α = 0.8) in the Murray Estuary and all three forage fishes showed potential diet overlap (α ≥ 0.6) in the North Lagoon. Spatiotemporal variation of prey diversity was observed in smallmouth hardyhead while temporal variation of prey diversity was observed in sandy sprat and Tamar River goby. Overall, the prey abundance was temporally variable and predominantly regulated by salinity, pH, dissolved oxygen, water transparency and chlorophyll a in the Murray Estuary and Coorong. This study adds to our knowledge on dietary overlap and resource partitioning among small-bodied forage fishes mediated by environmental factors in the Murray Estuary and Coorong.     

Collapse of the native ruffe (<Emphasis Type="Italic">Gymnocephalus cernua</Emphasis>) population in the Biesbosch lakes (the Netherlands) owing to round goby (<Emphasis Type="Italic">Neogobius melanostomus</Emphasis>) invasion

We investigated the change in benthic fish communities in three artificial lakes of the Biesbosch area in the Netherlands between two time periods: before and after the invasion of round goby (Neogobius melanostomus). Native ruffe (Gymnocephalus cernua), the dominant species in benthic gillnet and littoral beach seining catches before the invasion, almost completely disappeared in all lakes only 2 years after the invasion. We found a significant increase in 0 + perch (Perca fluviatilis) and, in some lakes, pikeperch (Sander lucioperca) abundance in gillnet catches after invasion. In the post-invasion period, the 0 + fish community was dominated by perch, and the older fish community was dominated by round goby. The species richness of 0 + fish increased in the post-invasion period owing to the invasion of gobiids. However, it did not change for older fish between periods. Our results clearly show that, owing to a similar benthic lifestyle and high niche overlap, ruffe was the only species negatively influenced by the round goby invasion. The competitive superiority of round goby over ruffe is so strong that the once-dominant species of the overall benthic fish community collapsed after only a few years of coexistence.     

Candidaemia Observed at a University Hospital in Milan (Northern Italy) and Review of Published Studies from 2010 to 2014

Background

Candida species represent the fourth leading cause of nosocomial bloodstream infections (BSI) worldwide. However, candidaemia rates and species involved vary geographically.

Objectives

To evaluate the epidemiological pattern, risk factors for mortality and antifungal therapy of Candida BSI over a 5-year period (2008–2012) in a university hospital in northern Italy together with a review of the recent literature concerning candidaemia.

Methods

A retrospective cohort study cross-linked with microbiology database was performed.

Results

A total of 89 Candida BSI were identified in 42 males (47 %) and 47 females (52.8 %). The median age was 69 years (interquartile range 55–78) with 61.8 % of patients being older than 65 years. Considering all hospitalized patients, the overall incidence rate of candidaemia increased significantly from 2008 to 2012 (from 0.4 to 1.68 episodes per 10,000 patient/days) (p = 0.0001) with a mean linear increase in 5 new cases per year. Candida albicans was the predominant species isolated (64 %) followed by C. glabrata (19.1 %). The latter species was observed with significantly higher frequency in Internal Medicine and Intensive Care Units (ICU). In-hospital crude mortality was 41.6 %.

Conclusions

Candidaemia is an increasing BSI in our university hospital, in accordance with that observed in northern Italy, and it is still associated with high in-hospital crude mortality.     

Seasonal feeding ecology of co-existing native and invasive benthic fish along a nearshore to offshore gradient in Lake Michigan

Relative abundance, diet composition and feeding strategy were determined for three benthic fish, the native deepwater sculpin Myoxocephalus thompsonii (Girard, 1851) and slimy sculpin Cottus cognatus (Richardson, 1836), and the invasive round goby Neogobius melanostomus (Pallas, 1814), along a nearshore to offshore gradient in southeastern Lake Michigan during March–December 2010, 2015, and 2016. Round goby were most abundant in the nearshore (<25 m), slimy sculpin were most abundant in the transitional zone (35–65 m), and deepwater sculpin were most abundant in the offshore zone (>75 m). Despite a large degree of spatial separation, some species did overlap, with slimy and deepwater sculpin occurring in sympatry throughout the year in the offshore and transitional zones, and round goby overlapping with both sculpin species seasonally in the transitional zone. Deepwater sculpin exhibited specialization on Mysis diluviana in all depth regions. Slimy sculpin in the offshore reduced diet overlap with deepwater sculpin by specializing on fish eggs during spring and fall, whereas in the transitional depth zone, there was considerable overlap between sculpin species due to the high importance of Mysis in diets. The invasive round goby had a mixed diet, with some diet overlap with native sculpin, especially slimy sculpin, in the transitional zone. In the nearshore zone, round goby displayed a generalized diet with many prey contributing to the diet, but the average contribution of any prey was generally low. Spatial separation and variable feeding strategies help reduce, but not eliminate shared resource use amongst these benthic fish in Lake Michigan.     

Physical localization of rRNA genes by fluorescence in situ hybridization (FISH) and analysis of spacer length variants of 45S rRNA (slvs) genes in some species of genus Sesbania

The somatic chromosome numbers 2n = 12 in S. macrantha, S. coerulescens and 2n = 24 in S. simplicuscula were determined, additionally the contradictory chromosome numbers of S. bispinosa (2n = 12, 13, 14, 24) and S. pachycarpa (2n 12, 14) were determined as 2n = 24 and 2n = 14, respectively. The number of 5S rDNA sites in chromosome pair 1 was highly conserved in all the diploid and tetraploid species studied irrespective of their geographic distribution, suggesting that all diploid and tetraploid species/cytotypes of Sesbania analyzed in the present study are in close proximity. Cytogenetic mapping of the 45S multi-gene family was also carried out using fluorescence in situ hybridization. 45S rDNA was consistently located on short or long arms of two sub-metacentric chromosome pairs except on one chromosome pair in S. macrantha and on three chromosome pairs in S. bispinosa and S. cannabina. Out of these nine species, we observed the homogenization of intergenic spacer in six species and find only one spacer length variant (slv) located on one to three chromosome loci. However, three of the species were observed to have two slvs located on two different chromosomes. The species were grouped as per their evolutionary relationship on the basis of the results of the present study.     

Cold-induced changes affect survival after exposure to vitrification solution during cryopreservation in the south-west Australian Mediterranean climate species Lomandra sonderi (Asparagaceae)

There is limited knowledge of the effects of exposure to low temperatures in the unique Mediterranean climate plant species of Western Australia. We have thus investigated the effect of low temperature on cryogenic tolerance in Lomandra sonderi, an endemic perennial species of southwest Western Australia. Lomandra sonderi plants were preconditioned in tissue culture at constant 23 °C (12 h light/dark cycle) or alternating 20/?1 °C (16 h light and 8 h dark cycle). Shoot tips from both conditions were analysed for their phospholipid, sterol and soluble sugar compositions. Shoot tips were also cryoexposed via a droplet-vitrification protocol. Survival in both preconditioning regimes for cryoexposed and non-cryoexposed samples was the same, but plants from the 20/?1 °C regime displayed an improved tolerance to the overall cryopreservation process in both cryoexposed and non-cryoexposed samples, thereby eliminating exposure to liquid nitrogen as a primary cause of reduced post-cryogenic viability. Preconditioning of in vitro shoots of L. sonderi at 20/?1 °C induced significant increases in phosphatidylcholine (from 7.30 ± 3.46 to 22.2 ± 7.80 ng mg^?1 FW) and increases in several soluble sugars (fructose, galactose, glucose, sucrose) compared to shoots incubated at 23 °C—changes consistent with known cold acclimation responses in plant species generally—but sterol content remained largely unchanged. Analysis of electrolyte leakage in shoot tips from both preconditioning regimes generated a significantly lower LT₅₀ value in the 20/?1 °C samples (?5.45 ± 0.53 °C) over the 23 °C samples (?2.5 ± 0.08 °C). Increased tolerance to cryoexposure in L. sonderi appears to lie mainly with acclimation-induced changes in membrane composition and promotion of membrane stability and hence increased resistance to freeze damage.     

Spawning vocalizations in male freshwater gobiids (Pisces,Gobiidae)

Synopsis Males of two freshwater Italian gobies, the common goby, Padogobius martensii and the panzarolo goby, Knipowitschia punctatissima, emit trains of low-frequency pulses, i.e. drumming sounds, in the presence of a ripe female in the nest. In P, martensii the drumming sound is usually followed by a tonal sound (complex sound). Examination of the pulse structure suggests that these sounds are produced by muscles acting on the swimbladder. Both species exhibited high emission rates of spawning sounds, especially before the beginning of oviposition. Moreover, spawning sound production ceased only after the female abandoned the nest, which always occurred at the end of oviposition. This is the first study reporting the production among fishes of distinct sounds during protracted spawning. Unlike sounds produced just before mating by fishes with planktonic or demersal zygotes, the spawning sound production of these gobies does not function to coordinate mating events in the nest. The presence of a two-part vocalization by male P. martensii even suggests a functional dichotomy of spawning sounds in this species.     

Genetic diversity analysis of chrysopidae family (insecta,neuroptera) via molecular markers

In entomology, improvement of molecular methods would be beneficial tools for accurate identification and detecting the genetic diversity of insect species to discover a corroborative evidence for the traditional classification based on morphology. The aim of this study was focused on RAPD-PCR method for distinguishing the genetic diversity between eight species of Chrysopidae family. In current research, many specimens were collected in different locations of Tehran province (Iran), between them 24 specimens were identified. The wing venation, male genitalia and other morphological characters were used for identification and also the sexing of species was recognized with study of external genitalia. Then, the DNA was extracted with CTAB method. The RAPD-PCR method was carried out with twenty random primers. The agarose gel electrophoresis was used for separation of the PCR products. Based on electrophoresis results, 133 bands were amplified and between them, 126 bands were poly-morph and others were mono-morph. Also, among the applied primers, the primers OPA02 with 19 bands and OPA03 with 8 bands were amplified the maximum and minimum of bands, respectively. The results showed that 80.35 and 73.21 % of genetic similarity existed between Chrysopa pallens–Chrysopa dubitans, and between the Chrysoperla kolthoffi and Chrysoperla carnea, respectively. The minimum (45.53 %) of genetic similarity was observed between C. kolthoffi and C. dubitans, and the maximum (0.80 %) was seen between C. pallens and C. dubitans.     

Molecular analysis reveals lowbush blueberry pest predation rates depend on ground beetle (Coleoptera: Carabidae) species and pest density

Molecular gut-content analysis allows determination of pest predation by field-collected predators. Ground beetles (Coleoptera: Carabidae) common in lowbush blueberries may consume blueberry spanworm, Itame argillacearia (Packard) (Lepidoptera: Geometridae), and blueberry flea beetle, Altica sylvia Malloch (Coleoptera: Chrysomelidae), providing pest suppression. Using newly developed pest specific primers, laboratory feeding trials showed that the median detection time (MDT) for blueberry spanworm in the largest beetle, Carabus nemoralis O.F. Müller, was 3.7 h, whereas Poecilus lucublandus (Say) and Pterostichus mutus (Say) had MDTs between 27.1 and 31.6 h for both pests. At a field-site with high pest abundances, the probability of detecting blueberry spanworm and blueberry flea beetle DNA was greater in P. lucublandus, 26 and 39 % respectively, than in P.mutus, 8 and 20 % respectively. Only 0 and 1 % of P. lucublandus and P. mutus, respectively, tested positive for blueberry spanworm DNA at a second site with low abundance. At the first site, the probability of detecting pest DNA in both ground beetle species was positively related to pest density. Higher pest DNA detection rates and captures of ground beetles corresponded to field areas where significant pest reductions occurred from late May to early June. Conservation of predatory carabid beetles could lead to valuable biological control in lowbush blueberries.     

Freshwater Crustacea (Cladocera,Copepoda) of Iceland: taxonomy,ecology, and biogeography

Of the many types of freshwater bodies across Iceland (e.g., lakes, springs, rivers, and ponds), greater effort has been invested in researching the freshwater Crustacea (Cladocera, Copepoda) of more permanent, larger, and deeper water bodies than on smaller or more ephemeral sites. To address this, we described the fauna of 12 shallow freshwater bodies distributed from the coast to the central highlands of Iceland. We identified 16 species in 11 genera belonging to six families of Cladocera, and 12 species in eight genera belonging to four families of Copepoda. Five of the species we identified (Alona werestschagini, Cyclops vicinus, Daphnia cristata, Diacyclops abyssicola, and Heterocope borealis) represent new distribution records for Iceland, increasing the number of species now known from this region to 34 Cladocera and 38 Copepoda taxa. Additionally, we discuss the taxonomy of some species with doubtful taxonomical status. Six crustacean taxocenes are described, each characterized by the dominance of different taxa, with bottom sediment characteristics best explaining species assemblage structure. We evaluated the relationships between Icelandic Cladocera and Copepoda faunas and those of the adjacent Svalbard, Faroe, and Shetland Islands, Greenland, and the mainland Norway. The taxonomic composition of the Icelandic fauna is dominated by widely distributed Holarctic, and secondarily Palaearctic and Nearctic species, and is more similar to the faunas of the major North Atlantic islands (64.2–71.8 % similarity) than it is to that of continental Norway.     

Effect of temperature on development and reproduction of Proprioseiopsis asetus (Acari: Phytoseiidae) fed on asparagus thrips,Thrips tabaci

Thrips tabaci Lindeman (Thysanoptera: Thripidae) is one of the most important pests of asparagus in China. In this study the effects of five constant temperatures (15, 20, 25, 30 and 35 °C) on the growth, survivorship and reproduction of Proprioseiopsis asetus (Chant) (Acari: Phytoseiidae) fed on T. tabaci was examined under laboratory conditions. Development time of immatures decreased with increasing temperature. The lower egg-to-adult developmental threshold (T ₀) and thermal constant (K) of P. asetus were estimated at 15.2 °C and 75.8 degree days by means of a linear model. Fertilized females fed on T. tabaci produced offspring of both sexes, whereas the offspring sex ratio [♀/(♀ + ♂)] of P. asetus at 20–35 °C was female-biased (0.68–0.78) and not significantly influenced by temperature. Survivorship during immature development was significantly influenced by temperature, and was especially low at 15 °C. Pre- and post-oviposition periods of fertilized females shortened with the increase in temperature. The longest oviposition period was 20.4 days, at 25 °C, whereas at 15 °C the mites did not reproduce. Maximum average life time fecundity and mean daily fecundity was recorded at 25 and 35 °C, respectively; the intrinsic rate of increase ranged from 0.05 (20 °C) to 0.17 (35 °C). The results indicate the capability of P. asetus to develop and reproduce at a broad range of temperatures, especially above 25 °C, which can be used for better management of T. tabaci in asparagus.     

Light and temperature conditions affect bioflavonoid accumulation in callus cultures of Cyclopia subternata Vogel (honeybush)

Callus cultures of the endemic South-African legume Cyclopia subternata were cultivated under varying light and temperature conditions to determine their influence on biomass growth and bioflavonoids accumulation. Experimental modifications of light included complete darkness, light of different spectral quality (white, red, blue and yellow) and ultraviolet C (UVC) irradiation. The calli were also subjected to elevated temperature or cold stress. Among the tested light regimes, cultivation under blue light resulted in the highest levels of hesperidin (H)—118.00 mg 100 g^?1 dry weight (DW) on 28 days of experiment, as well as isoflavones: 7-O-β-glucosides of calycosin (CG), pseudobaptigenin (PG) and formononetin (FG)—28.74, 19.26 and 10.32 mg 100 g^?1 DW, respectively, in 14-days old calli. UVC irradiation applied on 20 days stimulated the accumulation of H (204.14 mg 100 g^?1 DW), CG (31.84 mg 100 g^?1 DW) and PG (18.09 mg 100 g^?1 DW) in 28 days culture by 140, 46 and 165 %, respectively, without negatively influencing callus growth. Low temperature (13 °C) increased CG content by over 1,500 % (235.29 mg 100 g^?1 DW) when applied during the whole 28-days growth cycle, at the same time causing 95 % decrease in culture growth in comparison to reference calli maintained at 24 °C. On the contrary, elevated temperature (29 °C) applied during the second half of the culture period resulted in over 300 and 500 % increase in CG and PG content (61.76 and 58.89 mg 100 g^?1, respectively) while maintaining relatively high biomass yield.     

Phylogenetic relationships among Phytopythium species,and re-evaluation of Phytopythium fagopyri comb. nov., recovered from damped-off buckwheat seedlings in Japan

We examined the phylogenetic relationships among Phytopythium species using the rDNA ITS region, the LSU rDNA region, and the mitochondrial coxI and coxII genes. The genus was resolved into three monophyletic clades (1–3). Clade 1 was the largest clade, composed of 12 known species. Clades 2 contained two known and one new species candidate and clade 3 contained two known species. Three isolates in clade 2 (FP1, HonMa, and a strain designated as P. helicoides CBS293.35) formed a monophyletic group with high bootstrap support. This monophyletic group was distinct from P. helicoides sensu stricto. All three isolates came from damped-off buckwheat seedlings. The isolates were morphologically identical with one another and were characterized by globose, sub-globose, or pyriform sporangia with apical papillae; internally or internally nested proliferating sporangia; simple sympodia; coiling antheridial stalks; and wavy, sessile, or clavate antheridial cells. The isolates grew at temperatures between 15 °C and 40 °C, and the optimum temperature was 30 °C, with a radial growth rate of 20 mm/24 h. The phylogenetic and morphological analyses indicated that these isolates belong to a distinct species, which was previously under the genus Pythium, named here Phytopythium fagopyri comb. nov.     

A New Species of Rhaponticoides (Asteraceae) from Southern Italy

A new diploid (2n?=?30) species, Rhaponticoides calabrica, is described from Calabria and Basilicata (southern Italy). This species differs from the closely related R. centaurium – an endemic of Apulia and northern Basilicata – by different flower colour (white in the former, purplish in the latter), width of membranous margin of phyllaries (1.8?±?0.4 mm vs 0.8?±?0.3 mm) and pappus length (6.8?±?0.9 mm vs 9.1?±?1.0 mm). The two species are completely allopatric and seem to have also different chromosome numbers.     

Feeding habits of an endemic fish,Oxygymnocypris stewartii,in the Yarlung Zangbo River in Tibet,China

Feeding habits of Oxygymnocypris stewartii were investigated based on monthly sampling in the Yarlung Zangbo River from August 2008 to August 2009. The gut contents of 194 individuals were analysed and quantified with numerical and gravimetric methods. This species can be considered a generalized and opportunistic predator feeding both on teleosts and aquatic insects. A multivariate analysis revealed noticeable variation in O. stewartii diet composition with fish size and season. The smaller specimens fed primarily on Cobitidae and Hydropsychidae. As they grew, Cyprinidae and Chironomidae larvae became important prey. The preferred food items were teleosts in summer and autumn. For winter and spring, the predominant prey switched to chironomidae larvae. Diet composition did not significantly vary between the sexes. Finally, a significant and positive correlation between predator and prey length was found. These findings provide the fundamental information better understanding the role of this important endemic species in the Yarlung Zangbo River food web.     

Population genetic structure of endangered Mongolian racerunner (Eremias argus) from the Korean Peninsula

The Mongolian racerunner (Eremias argus) is a small lacertid lizard species, and its distribution range encompasses the Korean Peninsula, Mongolia, China and Russia. Eremias argus is widespread, but populations on the Korean Peninsula are small and declining, provoking concerns that genetic diversity is being lost. This species is currently listed under the Protection of Wild Fauna and Flora Act in South Korea. In this study, nine novel microsatellites for E. argus were developed with a biotin-enrichment method and used to understand its population genetic structure and delineate conservation units on the Korean Peninsula. Overall, low intrapopulation genetic diversity was observed (mean number of alleles per locus = 2.463; mean H _E = 0.398) from 10 populations investigated (n = 110). Two populations (among five with n≥ 10) showed an excess of heterozygosity expected under HWE relative to that expected at mutation-drift equilibrium, indicating severe reduction in population sizes. With only a few exceptions, the overall genetic differentiation among populations was substantial with the high levels of pairwise-F _ST (0.006–0.746) and -R _ST (0.034–0.940) values. The results of Bayesian STRUCTURE analysis showed that E. argus populations on the Korean Peninsula were most likely partitioned into three genetic clusters. Taken all together, such low levels of gene flow and strong genetic structuring have critical implications for the conservation of this endangered species and its management.     

Plastron respiration in marine intertidal oribatid mites (Acari,Fortuyniidae and Selenoribatidae)

Plastron respiration was investigated in the fortuyniid Alismobates inexpectatus, Fortuynia atlantica and the selenoribatid Carinozetes bermudensis. All these taxa inhabit intertidal zones of subtropical and tropical coasts and are exposed to tidal flooding. The utilization of plastron mechanisms enables these species to respire under water. Cerotegumental structures consisting of micropapillae and pillars bearing an outer sheet provide extensive areas where air is retained supplying the tracheal system with oxygen. A. inexpectatus and F. atlantica possess a dorsal and ventral plastron connected laterally by cuticular channels of the van der Hammen’s organ, whereas the specific configuration of these channels varies between the genera. The plastron of Carinozetes species spans the whole body except for all movable parts as legs and genital and anal valves. Plastron structures in juveniles of the families Fortuyniidae and Selenoribatidae were investigated for the first time in detail. Air-retaining cerotegument is also present in immatures of these taxa but is concentrated along lateral and ventral folds where series of pores lead into supposed tracheal organs. In juveniles of A. inexpectatus and F. atlantica, these organs are tubes with a length of approximately 3–15 μm, and in Carinozetes immatures, these organs are short saccules (0.5–1 μm).