The present study provides new data concerning the morphology of the male genitalia of Aphididae and unifies their nomenclature. The structure of the male genitalia of 31 species from 26 genera of Aphididae was studied with light and scanning electron microscopy. In the studied species, the genitalia of males consist of a phallus composed of the sclerotized basal part with its articulation and a membranous apical part—an aedeagus. Laterally of the phallus, there is a pair of setose parameres. The shape of the aedeagus, the shape and length of the sclerotized basal part and its articulation as well as the variability of parameres in their form and the number of setae are recognized as important systematic signs of the genitalia. These characters are considered in conjunction with the phylogenetic relationships among the studied taxa.

Aphidoidea, endosymbiotic bacteria, bacteriocytes, transovarial transmission of endosymbiotic bacteria The ultrastructure, distribution and transovarial transmission of endosymbiotic bacteria in representatives of six aphid families: Eriosomatidae (Pemphigus spyrothecae, Prociphilus fraxini), Anoeciidae [Anoecia (Anoecia) corni], Drepanosiphidae [Mindarus abietinus, Sipha (Rungsia) maydis, Clethrobius comes, Myzocallis (Lineomyzocallis) walshii], Thelaxidae (Thelaxes dryophila), Aphididae (Delphiniobium junackianum, Aphis viburni, Cavariella theobaldi, Macrosiphoniella tanacetaria) and Lachnidae (Schizolachnus pineti, Eulachnus rileyi) were studied at the ultrastructural level. The ovaries of aphids are accompanied by large organs termed bacteriomes that consist of giant cells termed bacteriocytes. The bacteriocyte cytoplasm is tightly packed with endosymbiotic bacteria. Ultrastructural observations have shown that the bacteria Buchnera aphidicola (primary symbiont of aphids) present in various species are characterized by significant differences in both size and organization of their cytoplasm. In the aphids, Prociphilus fraxini, Sipha (Rungsia) maydis, Thelaxes dryophila, Aphis viburni, Cavariella theobaldi, Macrosiphoniella tanacetaria, Eulachnus rileyi and Schizolachnus pineti, in addition to Buchnera aphidicola, secondary endosymbionts are also present. The bacteriocytes containing secondary endosymbionts are less numerous than those with Buchnera. In Eulachnus rileyi (Lachnidae), in addition to primary and secondary endosymbionts, there is a third type of microorganism. In all species examined both the primary and secondary endosymbionts are transovarially transmitted from mother to offspring.

The paper presents results of faunistic investigations of aphids (Aphidomorpha) in the Botanic Garden of the Jagiellonian University, Kraków, in the Kraków – Wieluń Upland. During two seasons of research (2011, 2012) two aphid species from the family Adelgidae and 50 species from the family Aphididae, associated with 66 host plants were recorded. The following species – Eriosoma anncharlotteae Danielsson, 1979, Capitophorus elaeagni (Del Guercio, 1894), Rhopalosiphoninus (Neorhopalosiphoninus) staphyleae staphyleae (Koch, 1854), Eulachnus brevipilosus Börner, 1940 and E. cembrae Börner, 1950 – are new for the Kraków – Wieluń Upland. Seven of the species recorded are regarded as alien to Poland.

The structure of the male reproductive system of 14 Chaitophorine species is discussed: Chaitophorus capreae, C. leucomelas, C. nassonovi, C. populeti, C. populialbae, C. salicti, C. salijaponicus niger, C. tremulae, C. truncatus, C. vittelinae, Sipha maydis, Periphyllus aceris, P. coracinus, P. lyropictus. All species, except Sipha maydis, which lives on Poacea (grasses), feed on trees of the families Aceraceae (maples) and Salicaceae (poplars and willows). On the basis of longitudinal sections, cross-sections (paraffin method) and total preparation, the following elements in the structure of the male reproductive system have been examined: the number of testis follicles and the stage of the spermatogenesis; the connection of follicles and vasa deferentia, the position and the histological structure of the wall of vasa deferentia; and the development accessory glands and ejaculatory duct. These characters were then used to supplement morphological data in order to verify the taxonomic position of Chaitophorinae.

The Chaitophorinae is a bionomically diverse Holarctic subfamily of Aphididae. The current classification includes two tribes: the Chaitophorini associated with deciduous trees and shrubs, and Siphini that feed on monocotyledonous plants. We present the first phylogenetic hypothesis for the subfamily, based on molecular and morphological datasets. Molecular analyses were based on the mitochondrial gene cytochrome oxidase subunit I (COI) and the nuclear gene elongation factor-1α (EF-1α). Phylogenetic inferences were obtained individually on each of genes and joined alignments using Bayesian inference (BI) and Maximum likelihood (ML). In phylogenetic trees reconstructed on the basis of nuclear and mitochondrial genes as well as a morphological dataset, the monophyly of Siphini and the genus Chaitophorus was supported. Periphyllus forms independent lineages from Chaitophorus and Siphini. Within this genus two clades comprising European and Asiatic species, respectively, were indicated. Concerning relationships within the subfamily, EF-1α and joined COI and EF-1α genes analysis strongly supports the hypothesis that Chaitophorini do not form a monophyletic clade. Periphyllus is a sister group to a clade containing Chaitophorus and Siphini. The Asiatic unit of Periphyllus also includes Trichaitophorus koyaensis. The analysis of morphological dataset under equally weighted parsimony also supports the view that Chaitophorini is an artificial taxon, as Lambersaphis pruinosae and Pseudopterocomma hughi, both traditionally included in the Chaitophorini, formed independent lineages. COI analyses support consistent groups within the subfamily, but relationships between groups are poorly resolved. These analyses were extended to include the species of closely related and phylogenetically unstudied subfamily Drepanosiphinae, which produced congruent results. Genera Drepanosiphum and Depanaphis are monophyletic and sister. The position of Yamatocallis tokyoensis differs in the molecular and morphological analyses, i.e. it is either an independent lineage (EF-1α, COI, joined COI and EF-1α genes) or is nested inside this unit (morphology). Our data also support separation of Chaitophorinae from Drepanosiphinae.