Geographic and chronographic variations of coloration in population of Polistes gallicus (Linnaeus, 1767) (Hymenoptera, Vespidae)

The article presents the results of studying geographic and chronographic colour variability of paper wasp Polistes gallicus (Linnaeus, 1767) in Kherson Area of Ukraine in 2004-2005. Colour and pattern variations on clypeus (6), mesonotum (3), the first tergite of abdomen (4) and the second tergite of abdomen (3) were investigated for 1839 wasps (queens and future foundresses). Colour and pattern variations on clypeus and mesonotum of 255 queens collected in May-June 2005 in three places of the Kherson Area (The Black Sea Reserve, Kherson and Khorly) didn’t differ, but colour variations on the first tergite of abdomen were significantly different in those three sites under study. Variability being of a clinal character, this allowed making a conclusion that the wasps of these three sites belonged to one and the same population. A comparison of colour variation frequencies for the Black Sea reserve subpopulation throughout 2004-2005 revealed similarity in clypeus and the first tergite of abdomen and significant differences for queens’ and future foundresses’ mesonotum. A change in colour variation of the population was expressed more significantly in 2004 and had cyclic character. The subpopulation as a whole maintained its stability in those characteristics. A possibility of such variability as a result of some selection factors is discussed

Reaction of parasitoids of social paper wasp Polistes dominula (Christ, 1791) on the mite infestation of the host

In 2003, 2005, 2011–2012 extensiveness and intensity of mite infestation of Sphexicozela connivens Mahunka, 1970 (Acari: Winterschmidtiidae) of social wasp Polistes dominula (Christ, 1791) pupae and adult sexual generation on colonies not infected and infected by parasitoids Latibulus argiolus (Rossi, 1790) (Hymenoptera: Ichneumonidae) and Elasmus schmitti Ruschka, 1920 (Hymenoptera: Eulophidae) were analyzed. It is shown that under the conditions of the Black Sea Biosphere Reserve (Southern Ukraine) the intensity of mite infestation in P. dominula colonies infected by Elasmus schmitti was lower than that in uninfected wasp colonies or colonies with L. argiolus. A negative correlation between intensity and extensiveness of mite infestation and the number (share) of wasp nest cells containing infected E.  schmitti brood was revealed. Mites on the host pupae containing E.  schmitti larvae were not recorded. Such correlations were not revealed in case of L. argiolus. Mites live both on host larvae and parasitoid larvae. Laboratory experiments have shown that E.  schmitti females, unlike L.  argiolus, leave heavily infected by mites wasp nest if they were there by accident. Parasitoids selectivity in regard to mite infestation of wasp host is considered in connection with their biology peculiarities