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1. Morphometries and seasonal occurrence of metacestodes of Neogryporhynchus cheilancristrotus (Cyclophyllidea: Dilepididae) in the blue bream (Ahramis ballerus) from the Oder River (Germany/Poland)

Creator:
Pietrock, Michael and Scholz, Tomáš
Format:
print
Type:
model:internalpart and TEXT
Subject:
Neogryporhynchus cheilancristrotus, Dilepididae, morphometries, seasonal occurrence, Ahramis ballerus, and Oder River
Language:
English
Description:
From May 1993 to April 1995, the seasonal occurrence of metacestodes of Neogryporhynchus cheilancristrotus (Wedl, 1855) (Cyclophyllidea: Dilepididae) in its second intermediate host, the blue bream Abramis ballerus (L.) was studied monthly in the Oder River on the borders of Germany and Poland. Based on the parasite specimens found, detailed data on their morphometries are presented. The metacestodes occurred in the blue bream intestine throughout the year (overall prevalence 27% and intensity 1-56 (mean 4.8) metacestodes per infected fish). Increased prevalences and mean intensities of infection were noted from March to June and November to December indicating that spring, late autumn and early winter are the main periods of new infections.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Seasonal occurrence, distribution and sampling indices for Myzus persicae (Hemiptera: Aphidoidea) and its parasitoids (Hymenoptera: Braconidae: Aphidiinae) on tobacco

Creator:
Kavallieratos, Nickolas G. , Athanassiou, Christos G. , Tomanović, Željko , Sciarretta, Andrea , Trematerra , Pasquale , and Žikić, Vladimir
Type:
article, model:article, and TEXT
Subject:
Aphidoidea, Myzus persicae, Aphidiinae, Aphidius colemani, Diaeretiella rapae, tobacco, seasonal occurrence, and sampling indices
Language:
English
Description:
Field studies were conducted, in order to assess the seasonal occurrence and the spatial distribution of Aphidius colemani Viereck, Aphidius matricariae Haliday, Diaeretiella rapae (M'Intosh), Praon staryi Kavallieratos & Lykouressis and Praon volucre (Haliday), all parasitoids of Myzus persicae (Sulzer) on tobacco. The experiments took place in western Greece (Agrinion, Aitoloakarnania), during the 1996 and 1997 growing seasons, in an area of approximately 2.5 ha, where tobacco was the main crop. The experimental field was insecticide-free and tobacco leaf samples (from the upper and lower half of plants) were taken from June until September, in both years. The distribution of the species found was also represented and discussed. Generally, high M. persicae densities were recorded in August (mid-season) of both seasons. The mummification rate showed a specific increasing trend late in the season (August-September). In 1996, the percentage of mummification reached almost 61% at the end of the period, whereas in 1997 it remained at very low levels (<2%). The density of M. persicae was higher on the leaves collected from the upper part of the plants than on those from the lower part, but without significant difference. In contrast, the numbers of mummified M. persicae individuals were significantly higher on leaves collected from the lower part of the plants than on those from the upper part in both years. The relative abundance of the aphidiine parasitoid species differed between the two years.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3. Seasonal prevalence of trematode cercariae in Clypeomorus bifasciata (Gastropoda: Prosobranchia) in Kuwait Bay

Creator:
Abdul-Salam, J., Sreelahta, B.S., and Ashkanani, H.
Format:
print
Type:
model:internalpart and TEXT
Subject:
Clypeomorus bifasciata, cercariae, seasonal occurrence, and Kuwait
Language:
English
Description:
Of 14,431 Clypeomorus bifasciata Sowerby, 1855 collected from Kuwait Bay between November 1992 and October 1993, 718 (5.0%) were shedding a total of 12 morphologically distinguishable ‘types’ of cercariae: 1 cystocercous, 2 echinos-tome, 1 furcocystocercous, 3 magnacercous, 2 megalurous, 1 microcercous and 2 ubiquità. Ubiquità I and furcocystocercous were the most prevalent species accounting for 66% and 25%, respectively, of total cercaria fauna. Double infections were recorded in only 6 (0.8%) of the infected snails. The overall prevalence of C. bifasciata shedding cercariae was highest (6-10%) in spring and summer, and species diversity was highest (11 species) in fall and spring. Seasonal variations in prevalence and diversity of cercariae were related to environmental factors and hosts behavior.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public