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Measuring the linear characteristics of chironomid larvae is easier and faster than measuring their mass. The relationships between them are approximated by parabolic equations. Generalized equations are provided for all chironomid larvae. However, these relations vary in different water bodies. Measurements of 1424 chironomid larvae representing several species were taken in Crimean waters with salinity ranging from 0 to 280 PSU. There was a high correlation between three traits. In the case of Baeotendipes noctivagus and Cricotopus gr. sylvestris, dimorphism was found in the "head capsule length– width" relationship. Salinity affects the head capsule. The exponent "b" varied from 1.43 to 3.06 in the "body length-mass" equation for B. noctivagus, and from 1.943 to 2.592 for C. gr. sylvestris. It is inappropriate to use only one coefficient "b" for all chironomid larvae. In B. noctivagus and Paratanytarsus confuses, the mass of one-size larvae decreased with increasing salinity. Salinity is not the only factor affecting the size and mass of chironomid larvae. [ABSTRACT FROM AUTHOR]

Coastal Lake Bardawil (Egypt) is one of the largest hypersaline lakes in the world. In 2009-2010, the authors studied composition, distribution and seasonal dynamics of copepods at 12 sites. A total of 10 species of copepods were recorded in zooplankton during the study period, including 5 Calanoida, 2 Cyclopoida and 3 Harpacticoida. Oithona nana was the most common and most abundant species. All copepods in the lake can be divided into three groups: 1) planktic species that form stable populations, 2) species of Mediterranean plankton incidentally entering the lake from the adjacent sea area, 3) benthic Cyclopoida and Harpacticoida that can be abundant in plankton. Two species - Acartia tonsa and A. danae were recorded here for the first time. The total abundance of copepods in the lake was significantly higher (90 times on average) compared to that observed in 2008-2009 in the waters of the Egyptian Mediterranean Sea. Since 1967, the complex of common and dominant copepod species in the lake has changed significantly. The total average annual copepod abundance varied: in 2002 - it was about 4000 ind. m-3, in 2004 - 152 000 ind. m-3, in 2005 - about 25 300 ind. m-3, and in 2009-2010 - about 56 000 ind. m-3. [ABSTRACT FROM AUTHOR]