Ameiridae Boeck and Argestidae Por revisited, with establishment of Parameiropsidae, a new family of Harpacticoida (Crustacea, Copepoda) from deep-sea sediments

Four new species of Parameiropsis are described from Angola and Guinea Basins and the Arctic Laptev Sea. The male of Parameiropsis poseidonicus sp. n. differs from that of P. neptuni sp. n. and P. senckenbergi sp. n. in antennule segmentation, length of the proximal aesthetasc, length of the outermost seta of the antennary endopod, degree of reduction of the mouthparts, relative length of the inner spine of the basis of thoracopod 1, shape of the furca and body length. The female of P. amphitriteae sp. n. differs from previously described females of other species in the smaller exopod and endpod of thoracopod 1, reduced armature of thoracopods 1–6, length of the outer setae of exopods and endopods of thoracopods 2–4, and mandible exopod weakly developed and fused to the basis. Parameiropsis is redefined by the following autapomorphies: presence of aesthetasc on 3rd segment of female antennule; antenna strong, with endopod curved upwardly, and shape of the outermost (strongly ornamented) spine; triangular labrum; elongated corpus mandibularis, gnathobasis very long; basis of mandibular palp unarmed; elongated maxillule, with long and flexible setae on praecoxal arthrite; basis of the maxilla with strongly modified claw. To discuss the phylogenetic position of Parameiropsis, we revaluated the subfamilies of Ameiridae (viz. Ameirinae and Stenocopiinae) and the family Argestidae. Anoplosomella and Malacopsyllus revealed to be not closely related to Ameiridae and are transferred to Argestidae, sharing with other members of this family the morphology of the mandible gnathobasis, armature of maxilla and armature and length of the first segment of the antennule. Argestoides prehensilis does not show any of the characters that we consider autapomorphic for Argestidae. Instead, it shows many characters in common with several Ameiridae species. Parameiropsis does not have any character that could justify its inclusion within Ameiridae or even within Podogennonta. It also cannot be included satisfactorily within Argestidae nor Exanechentera. Therefore, we here propose a new family for Parameiropsis, with unclear relationships within Harpacticoida. After these taxonomic rearrangements, Ameiridae and Argestidae are considered monophyletic based on certain maxilla characters that we consider autapomorphic for each group. A key to the identification of the known species of Parameiropsis is added at the end.     

Diversity of brood chambers in calloporid bryozoans (Gymnolaemata,Cheilostomata): comparative anatomy and evolutionary trends

Comparative anatomical studies of 12 species from 10 genera (Callopora, Tegella, Amphiblestrum, Parellisina, Corbulella, Crassimarginatella, Valdemunitella, Bryocalyx, Concertina, Cauloramphus) belonging to one of the largest and most diverse bryozoan taxa, the Calloporidae, and one species from the genus Akatopora belonging to the related taxon Antroporidae, were undertaken to elucidate the morphological diversity of brooding structures and to recognize main trends in their evolution. Most of the species studied possess ovicells (specialized brooding receptacles) formed by the distal and maternal (egg-producing) autozooids. The distal zooid can be an autozooid, a vicarious avicularium or a kenozooid. The calcified protective hood (ooecium) is an outgrowth from the distal zooid. Hyperstomial or prominent ovicells are most common. They were found in species of the genera Callopora, Tegella, Amphiblestrum, Parellisina, Corbulella, Bryocalyx and Concertina. Subimmersed ovicells were found in Valdemunitella, and immersed ovicells in Crassimarginatella and Akatopora. Cauloramphus has an internal brooding sac and a vestigial kenozooidal ooecium, budded by the maternal zooid. Based on the structure of the brooding organs, the following evolutionary trends can be recognized within the group: (1) reduction of the distal (ooecium-producing) zooid, (2) immersion of the brooding cavity correlated with a reduction of the ooecium and ooecial vesicle and with changes in the ovicell closure and the structure of the brood chamber floor, (3) reduction of the calcification of the ectooecium, and (4) transition from bilobate to entire ooecium. The trend towards immersion of the brooding cavity could have evolved repeatedly within the Calloporidae. Transition from bilobate to entire ooecium is characteristic of the related taxon Cribrilinidae, showing a good example of parallel evolution of the ooecium in two closely related clades. Possible causes for the transformations described are discussed.     

Trends in the evolution of the pongid dentition

The question investigated in this paper is whether long-range, parallel trends in evolution can be sustained in divergent though closely related lines. This study examines fossil and recent pongid dentitions, testing the hypothesis of the existence of certain trends in the pongid dental evolution. These are: reduction of the cingulum in both upper and lower molars; morphological and metrical reduction in third molars; mesial movement of the metaconid; buccal shifting of the hypoconulid; and alteration of the Dryopithecus groove pattern. More broadly the study tests conclusions of a previous study concerning parallelism of trends in the hominoid dentition. The results of reduction of the cingulum, reduction of the third molar, and alteration of the occlusal pattern on the lower molars support the theory that similar, long-term trends can operate in the evolution of divergent, though closely related lines. They also demonstrate that morphological resemblances between two forms are not certain proof of recent divergence.     

New insights into the complex structure and ontogeny of the occipito‐vertebral gap in barbeled dragonfishes (Stomiidae,Teleostei)

In all stomiid genera there is an occipito‐vertebral gap between the skull and the first vertebra bridged only by the flexible notochord. Morphological studies from the early 20th century suggested that some stomiid genera have 1–10 of the anteriormost centra reduced or entire vertebrae missing in this region. Our study reviews this previous hypothesis. Using a new approach, we show that only in Chauliodus, Eustomias and Leptostomias gladiator vertebral centra are actually lost, with their respective neural arches and parapophyses persisting. We present results from a comparative analysis of the number and insertion sites of the anteriormost myosepta in 26 of the 28 stomiid genera. Generally in teleosts the first three myosepta are associated with the occiput, and the fourth is the first vertebral myoseptum. The insertion site of the fourth myoseptum plays an important role in this analysis, because it provides a landmark for the first vertebra. Lack of association of the fourth myoseptum with a vertebra is thus evidence that the first vertebra is reduced or absent. By counting the occipital and vertebral myosepta the number of reduced vertebrae in Chauliodus, Eustomias and Leptostomias gladiator can be inferred. Proper identification of the spino‐occipital nerves provides an additional source of information about vertebral reduction. In all other stomiid genera the extensive occipito‐ vertebral gap is not a consequence of the reduction of vertebrae, but of an elongation of the notochord. The complex structure and ontogeny of the anterior part of the vertebral column of stomiids are discussed comparatively. J. Morphol. 271:1006–1022, 2010. © 2010 Wiley‐Liss, Inc.     

Levels of Selected Trace Elements, Phytohormones, and Sugars in Pseudomonas-Infected Lycopersicum esculantum Mill Plants

The present study investigated the levels of trace elements (Zn, Cu, Fe, Pb, and Cd), major elements (Ca and K), phytohormones (trans-Zeatin [t-Z] and gibberellic acid [GA]), and sugars (sucrose and glucose) following inoculation with Pseudomonas syringae pv. tomato strain. The results of the trace elements analysis showed that Fe (in the first, fourth, eighth, and tenth study days), Cd (in the fourth, eighth, and tenth study days), Cu (in the fourth and eighth study days), and Zn (in the eighth and tenth study days) increased in bacterium-infected tomato plants, compared to healthy plants. The levels of Pb, Ca, and K did not meaningfully determine a change after inoculation with pathogen. In this vein, the increase accumulation rates of Cu, Zn, and Fe in the injured plants can be an important indicator for the plant defense processes towards pathogen attack. Furthermore, in the first, fourth, eighth, and tenth study days, the glucose and sucrose contents crucially decreased in bacterium-infected plants compared to the control groups. The lowest level of sucrose in bacterium-infected plants was observed on the first day. The findings displayed that, when endogenous t-Z levels did not change after inoculation with virulent bacterium strain, there was a reduction in the first, fourth, eighth, and tenth days in the level of GA when compared with the control group levels. Therefore, there may be a link between lower GA level and enhancement in the expression of defense-related genes. The results of this study showed that there are complex relationships among levels of sugar, trace element, and endogenous phytohormone in the regulation of defense mechanisms against bacterial pathogen attacks.     

Cannibalism of parasitoid‐attacked conspecifics in a non‐carnivorous caterpillar

Cannibalism, the killing and consumption of conspecifics, can even occur in insect species typically considered to be non‐carnivorous. Of particular interest is the cannibalism of parasitoid‐attacked conspecifics, which could reduce parasitism levels in subsequent generations for that conspecific population. This study reports on the occurrence and some of the consequences of cannibalism in parasitoid‐attacked obliquebanded leafroller, Choristoneura rosaceana (Harris) (Lepidoptera: Tortricidae). We show that larvae of C. rosaceana, which is considered to be an herbivorous caterpillar species, did not prey upon live conspecifics, but readily consumed conspecifics attacked by Habrobracon gelechiae Ashmead (Hymenoptera: Braconidae). Further examination found that C. rosaceana larvae feeding on parasitoid‐attacked conspecifics, since their fourth instar, suffered a higher mortality and reduction in body size than those fed on plant material only. The cannibalism of attacked conspecifics did not appear to offer any nutrient benefits for the cannibal. To our best knowledge, this is the first empirical example of the occurrence and some of the consequences of cannibalism by a non‐carnivorous insect on its parasitoid‐attacked conspecifics. We discuss the adaptive significance of such cannibalism on parasitoid‐attacked conspecifics with respect to a trans‐generational fitness gain for the population through the killing of the parasitoids, thereby reducing parasitism in subsequent generations.     

Centers of mass and weight distribution in spiders of the family uloboridae

In the Uloboridae, web reduction is accompanied by changes in opisthosomal shape, leg length, and web-monitoring tactics. These morphological changes make reduced-web spiders more cryptic and alter their leg leverage and centers of mass. When compared with the orb-weaver Uloborus glomosus, the irregular, reduced-web spider, Miagrammopes animotus, invests more mass in its prosoma and first legs. However, the latter species' elongate opisthosoma posteriorly shifts this region's center of mass, causing the relative position of its composite center of mass and the distribution of weight between its first and fourth legs to be similar to that of the orb-weaver. Like these species, the opisthosomal center of mass of the triangle-weaver, Hyptiotes cavatus, lies near its midpoint. However, the shorter first legs and rounder, heavier opisthosoma of Hyptiotes posteriorly shift its composite center of mass and distribute more of its weight onto its fourth legs. Consequently, the morphology of M. animotus can be adequately explained by its adaptiveness for web manipulation, balance, and weight distribution and the crypsis that these features confer as an ancillary advantage. In contrast, anatomical changes in H. cavatus are better explained as adaptations for web manipulation and crypsis.     

Habrobathynella nagarjunai n. sp., the second representative of Bathynellacea (Crustacea, Syncarida) from groundwaters of South India

A new species of the genus Habrobathynella Schminke, 1973, i.e. H. nagarjunai n.sp., is described from the groundwater of the Nagarjuna University campus near Guntur town, South India. One of the principal criteria in the original definition of Habrobathynella is amended to accommodate the new species. H. nagarjunai n.sp. differs from its three congeners, i.e. H. milloti (Delamare & Paulian, 1954), H. jeanneli (Delamare & Paulian, 1954) from Madagascar, and H. schminkei Reddy, 2002 from India, in several essential morphological details: the sympodite of uropod bears 8–10 similar spines; the apophysis on segment 4 of the antennule is short; of the two setae on the exopodite of uropod, one is apical and the other subapical in position; the basal segment of maxilla has three unequal setae; the male thoracopod VIII is relatively elongate. H. nagarjunai n. sp. is the second representative of the groundwater (eustygobiont) Bathynellacea in South Asia. Furthermore, a key to the identification of Habrobathynella spp. is given.     

Morphometric variations in the housefly,Musca domestica (L.) with latitude

Morphologic analysis of geographic strains of Musca domestica carried out on natural and laboratory experiments starting with 400 and 800 eggs showed phenotypic variations related with latitude. Females of the natural populations showed clines for several morphological traits of the wing, whereas male flies showed a reduction in the dispersion measures (s ² and CV) of wing width and length. The same reduction was obtained for males, females and total number of flies of the natural populations in dispersion of the number of bristles on the fourth abdominal sternite. A significant negative correlation was observed for the head width of females and for the total number of flies emerged in the laboratory experiments started with 400 eggs. All flies produced by the experiments starting with 800 eggs showed a reduction in variability of dispersion of the bristles on the fourth abdominal sternite in the strains obtained from locations south of the area analyzed. Evolutionary aspects of these correlation coefficients between morphometric traits and latitude are discussed.     

More on the Homunculus Dpm4 and M1 and comparisons with Alouatta and Stirtonia (primates,platyrrhini, cebidae)

The little-worn deciduous fourth premolar and first molar of a mandibular fragment of Homunculus sp are compared with the cast of a previously described deciduous lower fourth premolar of Homunculus grandis and with lower molariform teeth of Alouatta and Stirtonia. Lower molars of Alouatta can be derived from those like Homunculus, but because of the fragmentary nature of the fossils, it cannot be demonstrated that Alouatta evolved from Homunculus or is even closely related. Comparison of mandibles and upper and lower molariform teeth of Alouatta with those of Stirtonia indicate wide divergence from some distant, possibly basic platyrrhine stock.     

Probing protein electrostatic interactions through temperature/reduction potential profiles

 The change in the equilibrium reduction potentials of the iron-sulfur proteins, Pyrococcus furiosus rubredoxin and P. furiosus ferredoxin, and heme protein, horse cytochrome c, has been calculated as a function of temperature using a numerical solution to the Poisson-Boltzman equation. Working curves for different internal dielectric constants were generated to best reproduce experimental observation. Based on a comparison of the experimental and simulated change in reduction potential with temperature, it is concluded that the dielectric constant of proteins is temperature-dependent and varies from protein to protein. For example, the temperature-dependent reduction potential of cytochrome c can only be simulated using a different temperature-dependent dielectric constant for each oxidation state, but this was not the case for rubredoxin or ferredoxin. The role of changes in ionization states of cytochrome c at alkaline pHs, where the reduction potential is known to be pH-dependent at room temperature, is also discussed in terms of electrostatic interaction energies as a function of temperature. It appears that temperature/reduction potential profiles may provide a direct method for measuring relative changes in internal protein dielectric constants. Received: 29 April 1996 / Accepted: 1 August 1996     

Critical Loads Changing with Time

The critical load is the maximal rate of contaminant addition that, over time, will result in environmental concentrations that do not exceed the highest acceptable concentration (i.e., the critical limit). Computationally, critical loads depend solely on critical limits and the expected rates at which contaminants are lost from the environmental media of concern. Losses include processes such as flushing (water bodies) or leaching (soils), sequestration in sediment, volatilization, and crop removal. A significant challenge is that loss rates will vary with time, especially in response to processes such as climate change. How should regulators deal with these changes with time? This Perspective compares the implications of three options where conditions are: (1) fixed to represent the present, (2) variable with no trend over time, and (3) variable with systematic trends (monotonic and cyclical) over time, and a fourth option using stochastic (probabilistic) evaluation of all plausible future conditions. Soil concentrations over 250 years were computed for each option. As expected, conditions that vary systematically with time can drastically change estimates of environmental concentration, and hence critical loads. However, if it is assumed that regulators periodically revisit critical load estimates taking into account changing conditions, long-term objectives can be achieved. One approach to changing conditions is to stochastically create a family of possible time series of conditions and outcomes. In the example developed here, the range of outcomes from the stochastic treatment encompassed those of the various time-series calculations. The regulatory implications of these findings are discussed.     

Phylogenesis and systematic arrangement of the family Calohypsibiidae Pilato, 1969 (Eutardigrada)1

The composition, the hylogenesis and the sstematic arrangement of the family Calohypsibiidae are discussed. To this imil the genera Calohypsibius, Haplomacrobiotus, Parhexapodibius, Hexa-podibius and Haplohexapoibius are to be ascried. Within the family two main hyletic lines can be distinguished. In one of them the diloclaws and the legs do not tend to be reduced (Calohypsibius), in the other the diploclaws and the legs have been affected by a more or less advanced and differentiated process of reduction. Within the latter ghyletic line two evolutionary trends can be distinguished; in the former the process of reduction as mostly affected the claws of the first three airs of legs where, by loss of the secondary branches, they have become single claws (Haplomacrobiotus). In the latter evolutionary trend the process of reduction has affected mostly the claws of the hind legs and, more or less, also the very legs. In the most primitive stem of this evolutionary trend the claws are dipclaws and they are present in all legs (Parhexapodibius). From the primitive stem a phyletic line as arisen in which the claws of the hind legs are quite lacking and the Kind legs are reduced to short stumps. This hyletic line is subdivided in two sister lines: in one of them the claws of the first three pairs of legs are reduced in size but maintain the secondary branches and they are then diloclaws (Hexapoditius), in the second phletic line the claws, by loss of the secondary branches, have become single claws (Haplohexapodibius). The systematic position of Apodibius is discussed. Up to this time it is not absolutely sure that this genus is belonging to the family Calohypsibiidae.     

Seasonal fluctuations of macroinvertebrate drift in a South Carolina Piedmont stream

The seasonal fluctuations of larval macroinvertebrate drift, exuvial drift and larval benthic density were quantitatively examined over a 1-year period in a fourth order, spring-fed stream in the Piedmont area of South Carolina. The drift was dominated by the mayfly Baetis spp. and by two species of blackfly (Prosimulium mixtum and Simulium jenningsi). Peak drift densities were noted during early spring and especially late summer. Strong correlations were noted between larval drift densities and exuvial drift, indicating a relationship between drift and seasonal growth and emergence patterns. Seasonal trends in drift and benthic densities, though less strongly correlated, were also generally similar.     

Effects of food nutritive quality and Bacillus thuringiensis onfeeding behaviour, food utilization and larval growth of spruce budworm Choristoneura fumiferana (Clem.) when exposed as fourth- and sixth-instar larvae

Abstract 1 Feeding behaviours, and lethal and sublethal (growth, development and food utilization) effects of Foray 48B, a commercial formulation of Bacillus thuringiensis (kurstaki), were investigated on fourth‐ and sixth‐instar spruce budworm larvae according to food nutritive quality. Nitrogen and soluble sugar content of artificial diets were modified to obtain three different qualities of food, simulating variations in nutritive quality of host tree. 2 Larval development times were longer for Bt‐treated larvae and pupal weights were reduced for sixth‐instar larvae only. Bt‐induced mortality levels were influenced by food quality. Ingested dose of Bt and feeding inhibition times were strongly affected by the Bt treatment, but food quality affected only fourth‐instar larvae. Except for food digestibility, nutritional indices were negatively affected by the Bt treatment and by the reduction in food quality. 3 Contrary to early treated larvae (fourth instar), larvae treated at the beginning of the sixth instar were not able to compensate for Bt injury and were consequently more affected by the Bt‐treatment both in terms of lethal and sublethal effects. 4 Bt efficacy was not directly related to the ingested dose. 5 Increase in larval vulnerability to Bt was more likely a consequence of a general stress induced by a less suitable food than a direct interaction between Bt and food nitrogen or sugar compounds. 6 The application of Bt on late‐instar larvae could be a successful operational strategy at low population levels when field sprays target the insect instead of foliage protection.     

Population trends and reproductive success of the European shag Phalacrocorax aristotelis on the Iberian Peninsula following the Prestige oil spill

In 2003, immediately following the Prestige oil spill in Galicia, Spain, we studied the population trends and reproductive performance of European shags (Phalacrocorax aristotelis) at oiled and unoiled colonies. This bird is an important member of the nearshore marine community, breeding in the area affected by the Prestige oil spill. The European shag feeds around the breeding colonies throughout the year, making it a useful indicator of environmental change. Before the oil spill, population trends were similar between oiled and unoiled colonies. Nevertheless, colonies located within the path of the oil suffered greater declines (ca. 10%) compared with pre-spill trends and with population trends at unoiled colonies. In 2003, the breeding success was 50% lower in oiled colonies compared with unoiled colonies. The data available from pre-spill years suggest that the annual reproductive success did not differ among colonies before the impact. European shags breeding at colonies affected by oil showed a negative initial impact from the Prestige oil spill. The reduction in reproductive success at oiled colonies may be due to sub-lethal effects of oil exposure or low food availability after the oil spill.     

The impacts of UV-B radiation on the regeneration of a sub-arctic heath community

The effects of ultraviolet-B radiation on regeneration after disturbance of a natural sub-arctic heathland have been investigated. Areas of pristine dwarf shrub heath were denuded of all above ground biomass in 1992 and exposed to enhanced UV-B (simulating a 15% depletion of the ozone layer). The resulting regenerated stem and leaf growth parameters were measured after four years on three dwarf shrubs, Vaccinium myrtillus, V. uliginosum and V. vitis-idaea and the grass Calamagrostis lapponica; leaves of the three dwarf shrubs were also analysed for UV-absorbing compounds and carbohydrates. Regeneration irrespective of treatment was slow, with Empetrum hermaphroditum failing to regenerate at all. Vaccinium myrtillus showed the most rapid regeneration attaining much of its original biomass in four years. There was a significant interaction between UV-B and year of regeneration in V. myrtillus; annual stem length increment showed an initial stimulation of 75% under enhanced UV-B in the first year of regeneration while a reduction of 16% was observed in the fourth year. Both V. uliginosum and V. vitis-idaea showed a reduction in annual stem length increment as regeneration progressed with a greater than 50% reduction in stem increment in the fourth year of regeneration compared to the first. Vaccinium uliginosum also showed an initial reduction in stem length increment of 40% under enhanced UV-B. None of the species were affected by enhanced UV-B in terms of total regenerated stem and leaf biomass or UV-absorbing compounds in regenerated leaf tissue. Total leaf carbohydrate and the ethanol/water soluble fraction in V. uliginosum were significantly increased by 29% and 31% respectively under enhanced UV-B. This suggests either a stimulation of photosynthesis or a reduction in sink size for photo-assimilates. Results are discussed in the context of the extremely slow regeneration of sub-arctic heath communities and the implications of contrasting UV-B effects on the regenerative ability of different species.     

Specificity of Developmental Resistance in Gypsy Moth （Lymantria dispar） to two DNA-Insect Viruses

Gypsy moth (Lymantria dispar) larvae displayed marked developmental resistance within an instar to L. dispar M nucleopolyhedrovirus (LdMNPV) regardless of the route of infection (oral or intrahemocoelic) in a previous study, indicating that in gypsy moth, this resistance has a systemic component. In this study, gypsy moth larvae challenged with the Amsacta moorei entomopoxvirus (AMEV) showed developmental resistance within the fourth instar to oral, but not intrahemocoelic, inoculation. In general, gypsy moth is considered refractory to oral challenge with AMEV, but in this study, 43% mortality occurred in newly molted fourth instars fed a dose of 5×10⁶ large spheroids of AMEV; large spheroids were found to be more infectious than small spheroids when separated by a sucrose gradient. Developmental resistance within the fourth instar was reflected by a 2-fold reduction in mortality (18%–21%) with 5×10⁶ large spheroids in larvae orally challenged at 24, 48 or 72 h post-molt. Fourth instars were highly sensitive to intrahemocoelic challenge with AMEV; 1PFU produced approximately 80% mortality regardless of age within the instar. These results indicate that in gypsy moth, systemic developmental resistance may be specific to LdMNPV, reflecting a co-evolutionary relationship between the baculovirus and its host.