40 research outputs found
Two new records of ladybirds (Col.: Coccinellidae) for the Iranian beetle fauna
The ladybird fauna of the croplands in the vicinity of Mashhad in the northeastern province of Khorasan-Razavi was studied from 2011 through 2012. The species Pharoscymnus brunneosignatus Mader and Scymnus schmidti FĂÂŒrsch, were collected and identified which are newly recorded for the Iranian beetle fauna
Comparative demography of the exotic Harmonia axyridis with other aphidophagous coccinellids reared on artificial diet
The harlequin ladybird, Harmonia axyridis: global perspectives on invasion history and ecology
The harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), is native to Asia but has been intentionally introduced to many countries as a biological control agent of pest insects. In numerous countries, however, it has been introduced unintentionally. The dramatic spread of H. axyridis within many countries has been met with considerable trepidation. It is a generalist top predator, able to thrive in many habitats and across wide climatic conditions. It poses a threat to biodiversity, particularly aphidophagous insects, through competition and predation, and in many countries adverse effects have been reported on other species, particularly coccinellids. However, the patterns are not consistent around the world and seem to be affected by many factors including landscape and climate. Research on H. axyridis has provided detailed insights into invasion biology from broad patterns and processes to approaches in surveillance and monitoring. An impressive number of studies on this alien species have provided mechanistic evidence alongside models explaining large-scale patterns and processes. The involvement of citizens in monitoring this species in a number of countries around the world is inspiring and has provided data on scales that would be otherwise unachievable. Harmonia axyridis has successfully been used as a model invasive alien species and has been the inspiration for global collaborations at various scales. There is considerable scope to expand the research and associated collaborations, particularly to increase the breadth of parallel studies conducted in the native and invaded regions. Indeed a qualitative comparison of biological traits across the native and invaded range suggests that there are differences which ultimately could influence the population dynamics of this invader. Here we provide an overview of the invasion history and ecology of H. axyridis globally with consideration of future research perspectives. We reflect broadly on the contributions of such research to our understanding of invasion biology while also informing policy and people
Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU
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Modelling the time-temperature relationship in cold injury and effect of high temperature interruptions on survival in a chill-sensitive collembolan.
1. Temperature- and time-dependent mortalities were studied and modelled in insects exposed in regimes with constant and alternating temperatures. In these experiments, freezing was not a cause of death. 2. Survival rates at a range of constant low temperatures (-5 to + 1 °C) and for different exposure periods (1-14 days) were measured in the summer acclimated springtail Orchesella cincta. 3. Daily interruptions of the cold exposure with short intervals at high temperature reduced mortality or slowed the increase of mortality. This effect was stronger at higher temperature (19 vs 5 and 12 °C) and increased with the duration of the interruption (0·25-2 h). 4. The injury was reversible when the cold exposure was limited to 2 days. 5. Survival in desiccated animals (14% water loss) was reduced. 6. It is suggested that the mortality of summer acclimated springtails is caused by a complex metabolic disorder and membrane changes at low temperatures
Tropical to subpolar gradient in phospholipid composition suggests adaptive tuning of biological membrane function in drosophilids
Harmonia axyridis in Europe: spread and distribution of a non-native coccinellid
Native to Asia, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) is considered an invasive alien ladybird in Europe and North America, where it was widely introduced as a biological control agent of aphids and coccids. In Europe, H. axyridis was sold by various biological control companies from 1995 in France, Belgium and the Netherlands, and was also intentionally released in at least nine other countries. It has spread very rapidly, particularly since 2002, and is now regarded as established in thirteen European countries. The established range extends from Denmark in the north to southern France in the south, and from Czech Republic in the east to Great Britain in the west. In this paper we map the spread and distribution of H. axyridis in Europe, and examine the situation on a country-by-country basis. We report first records of the species in five countries; Spain, Sweden, Denmark, Czech Republic and Italy; and first evidence of H. axyridis establishment in the latter three countries. Despite releases of H. axyridis in Portugal, Spain and Greece, there is little evidence of establishment in southern Europe. It is predicted that the spread and increase within Europe will continue and that H. axyridis will become one of the most widely distributed coccinellids in the continent
Melanism in a Chinese population of Harmonia axyridis (Coleoptera: Coccinellidae): a criterion for male investment with pleiotropic effects on behavior and fertility
Citation: Su, W., Michaud, J. P., Xiaoling, T., Murray, L., & Fan, Z. (2013). Melanism in a Chinese population of Harmonia axyridis (Coleoptera: Coccinellidae): A criterion for male investment with pleiotropic effects on behavior and fertility. Retrieved from http://krex.ksu.eduIn Beijing, China, females of Harmonia axyridis are promiscuous but prefer typical (succinea form) males to melanic ones in the spring generation, ostensibly due to the thermal disadvantages of melanism during summer. We used laboratory observations to test whether males invested differentially in females according to their elytral color, and whether male behavior was phenotype-dependent. Video-recording was used to monitor no-choice mating tests between virgin adults in all phenotype combinations and females were isolated post-copula to observe their egg retention times and reproduction over five days. Females tended to wait longer before using the sperm of melanic males, and melanic females delayed longer than succinic females. Melanic males spent longer in copula with succinic than melanic females and the latter received fewer bouts of male abdominal shaking that correlate with sperm transfer, regardless of the phenotype of their mate. Although melanic males abandoned melanic females faster than did succinic males, they remained in copula with females of both phenotypes for a longer period after shaking, suggesting a larger investment in mate guarding by the less-preferred male phenotype. Although female fecundity did not vary among phenotype combinations, egg fertility was lower for females mated to melanic males, suggesting a pleiotropic effect of melanism on male fertility in addition to its effects on male mating behavior