Cladocera of Alona affinis group from North America preserved in the collection of Professor D. G. Frey were investigated. A new subspecies of Alona ossiani Sinev, 1998 is described. Alona ossiani herricki ssp. nov. differs from the nominative subspecies in presence of 2-3 marginal denticles on postanal angle of male postabdomen, no differences between subspecies were revealed in the female mor...

We have constructed restriction-site maps of the mtDNAs in 13 species and one subspecies of the Drosophila obscura group. The traditional division of this group into two subgroups (affinis and obscura) does not correspond to the phylogeny of the group, which shows two well-defined clusters (the Nearctic affinis and pseudoobscura subgroups) plus a very heterogeneous set of anciently diverged spe...

Ocean acidification is caused by increasing amounts of carbon dioxide dissolving in the oceans leading to lower seawater pH. We studied the effects of lowered pH on the calanoid copepod Eurytemora affinis during a mesocosm experiment conducted in a coastal area of the Baltic Sea. We measured copepod reproductive success as a function of pH, chlorophyll a concentration, diatom and dinoflagellate...

One hundred specimens of unicorn leatherjacket, Aluterus monoceros purchased from markets of municipalities of Niterói and Rio de Janeiro from May to August 2006. The fishes were measured, necropsied, fileted and analysed their organs. Sixteen fishes were parasitized by nematode Anisakidae: Anisakis spp. and Contracaecum sp. with respectively, 1 and 16% of prevalence, 2 and 3.31 of mean intensi...

Since its original description as a chordate, the Late Devonian Scaumenella mesacanthi has been interpreted alternately as a prochordate, a larval ostracoderm and an immature acanthodian. For the past 30 years, these minute specimens were generally considered as decayed acanthodians, most of them belonging to Triazeugacanthus affinis. Among the abundant material of 'Scaumenella', we identified ...

Genetic elements that cheat Mendelian segregation by biasing transmission in their favor gain a significant fitness benefit. Several examples of sex-ratio meiotic drive, where one sex chromosome biases its own transmission at the cost of the opposite sex chromosome, exist in animals and plants. While the distorting sex chromosome gains a significant advantage by biasing sex ratio, the autosomes...

During routine inspection of a colony of albino western mosquitofish Gambusia affinis, approximately 10 females were discovered to have distended abdominal cavities. Cause for the distention was investigated by examination of tissue sections from four sacrificed individuals, all of which suffered severe ascites. Hermaphroditic gonads were seen in two of the fish.

biodegradable polysacharyd-based film was developed by incorporating pimpinella affinis essential oil (pao) into methyle cellulose (mc) at level of 0.5%, 1% and 1.5% v/v. then, its antimicrobial activity tested against 7 bacteria include staphylococcus aureus (ptcc 1431), pseudomonas aeruginosa (ptcc 1151), pseudomonas putida(ptcc 1691),esherichia coli (ptcc 3315), listeria monocytogenes (ptcc ...

chestnut-leaved oak (quercus castaneifolia) is one of the most important industrial species of the northern forests of iran. regeneration of this valuable species is limited due to several problems such us pests and the fungal diseases. in order to isolate and identify the fungi associated with oak seed, sampling was carried out during 2007 in shast-kalate forest at gorgan. collected seeds were...