Intraspecific Variability in Trionymus aberrans Goux, 1938 (Hemiptera: Coccomorpha: Pseudococcidae) with Description of the Second-Instar Nymph

The morphological characteristics of adult females of Trionymus aberrans Goux, 1938 (Hemiptera: Coccomorpha: Pseudococcidae) collected from post-industrial wastelands and other habitats in Poland and other countries were studied. Distinctive morphological variations were observed in the specimens from post-industrial wastelands in Poland. Scanning electron micrographs of the morphological characters of T. aberrans are provided. The presence of unusual pores, each with four loculi, was demonstrated for the first time in a species of Pseudococcidae. The importance of introducing additional morphological characters into the species description is discussed. New data on the frequency and host preferences of T. aberrans are also provided. This research is the first long-term study on scale insect species in post-industrial wastelands. The second-instar nymph of T. aberrans is described and illustrated and the presence of translucent pores on the hind coxae of this developmental stage is reported for the first time.

Is Every Vein a Real Vein? Cross-Section of the Wing of Matsucoccus Pini (Insecta, Hemiptera, Coccoidea: Matsucoccidae)

Wings of Matsucoccus pini males were studied. Using light and scanning electron microscopes, both sides of the wing membrane, dorsal and ventral, were examined. The presence of only one vein in the common stem was confirmed by the cross-section, namely the radius. The elements regarded as subcostal and medial veins were not confirmed as veins. On the dorsal side of the wings, a cluster of campaniform sensilla is shown for the first time in the family Matsucoccidae, through SEM, and two additional sensilla were found on the ventral side. There was a lack of alar setae, microtrichia as well as pterostigma. This is the second cross-section of the wing among scale insects. We propose the following nomenclature for the wings in the family Matsucoccidae: subcostal thickening (sct), radius (R), median fold (med) and anal fold (af).

Ovary structure and symbiotic associates of a ground mealybug, Rhizoecus albidus (Hemiptera, Coccomorpha: Rhizoecidae) and their phylogenetic implications

The ovary structure and the organization of its symbiotic system of the ground mealybug, Rhizoecus albidus (Rhizoecidae), were examined by means of microscopic and molecular methods. Each of the paired elongated ovaries of R. albidus is composed of circa one hundred short telotrophic-meroistic ovarioles, which are radially arranged along the distal part of the lateral oviduct. Analysis of serial sections revealed that each ovariole contains four germ cells: three trophocytes (nurse cells) occupying the tropharium and a single oocyte in the vitellarium. The ovaries are accompanied by giant cells termed bacteriocytes which are tightly packed with large pleomorphic bacteria. Their identity as Brownia rhizoecola (Bacteroidetes) was confirmed by means of amplicon sequencing and fluorescence in situ hybridization techniques. Moreover, to our knowledge, this is the first report on the morphology and ultrastructure of the Brownia rhizoecola bacterium. In the bacteriocyte cytoplasm bacteria Brownia co-reside with sporadic rod-shaped smaller bacteria, namely Wolbachia (Proteobacteria: Alphaproteobacteria). Both symbionts are transmitted to the next generation vertically (maternally), that is, via female germline cells. We documented that, at the time when ovarioles contain oocytes at the vitellogenic stage, these symbionts leave the bacteriocytes and move toward the neck region of ovarioles (i.e. the region between tropharium and vitellarium). Next, the bacteria enter the cytoplasm of follicular cells surrounding the basal part of the tropharium, leave them and enter the space between the follicular epithelium and surface of the nutritive cord connecting the tropharium and vitellarium. Finally, they gather in the deep depression of the oolemma at the anterior pole of the oocyte in the form of a 'symbiont ball'. Our results provide further arguments strongly supporting the validity of the recent changes in the classification of mealybugs, which involved excluding ground mealybugs from the Pseudococcidae family and raising them to the rank of their own family Rhizoecidae.

Fungal Associates of Soft Scale Insects (Coccomorpha: Coccidae)

Ophiocordyceps fungi are commonly known as virulent, specialized entomopathogens; however, recent studies indicate that fungi belonging to the Ophiocordycypitaceae family may also reside in symbiotic interaction with their host insect. In this paper, we demonstrate that Ophiocordyceps fungi may be obligatory symbionts of sap-sucking hemipterans. We investigated the symbiotic systems of eight Polish species of scale insects of Coccidae family: Parthenolecanium corni, Parthenolecanium fletcheri, Parthenolecanium pomeranicum, Psilococcus ruber, Sphaerolecanium prunasti, Eriopeltis festucae, Lecanopsis formicarum and Eulecanium tiliae. Our histological, ultrastructural and molecular analyses showed that all these species host fungal symbionts in the fat body cells. Analyses of ITS2 and Beta-tubulin gene sequences, as well as fluorescence in situ hybridization, confirmed that they should all be classified to the genus Ophiocordyceps. The essential role of the fungal symbionts observed in the biology of the soft scale insects examined was confirmed by their transovarial transmission between generations. In this paper, the consecutive stages of fungal symbiont transmission were analyzed under TEM for the first time.

Molecular characterization, ultrastructure, and transovarial transmission of Tremblaya phenacola in six mealybugs of the Phenacoccinae subfamily (Insecta, Hemiptera, Coccomorpha)

Mealybugs (Hemiptera, Coccomorpha: Pseudococcidae) are plant sap-sucking insects which require close association with nutritional microorganisms for their proper development and reproduction. Here, we present the results of histological, ultrastructural, and molecular analyses of symbiotic systems of six mealybugs belonging to the Phenacoccinae subfamily: Phenacoccus aceris, Rhodania porifera, Coccura comari, Mirococcus clarus, Peliococcus calluneti, and Ceroputo pilosellae. Molecular analyses based on bacterial 16S rRNA genes have revealed that all the investigated species of Phenacoccinae are host to only one type of symbiotic bacteria-a large pleomorphic betaproteobacteria-Tremblaya phenacola. In all the species examined, bacteria are localized in the specialized cells of the host-insect termed bacteriocytes and are transovarially transmitted between generations. The mode of transovarial transmission is similar in all of the species investigated. Infection takes place in the neck region of the ovariole, between the tropharium and vitellarium. The co-phylogeny between mealybugs and bacteria Tremblaya has been also analyzed.

Bacterial associates of Orthezia urticae, Matsucoccus pini, and Steingelia gorodetskia - scale insects of archaeoccoid families Ortheziidae, Matsucoccidae, and Steingeliidae (Hemiptera, Coccomorpha)

The biological nature, ultrastructure, distribution, and mode of transmission between generations of the microorganisms associated with three species (Orthezia urticae, Matsucoccus pini, Steingelia gorodetskia) of primitive families (archaeococcoids = Orthezioidea) of scale insects were investigated by means of microscopic and molecular methods. In all the specimens of Orthezia urticae and Matsucoccus pini examined, bacteria Wolbachia were identified. In some examined specimens of O. urticae, apart from Wolbachia, bacteria Sodalis were detected. In Steingelia gorodetskia, the bacteria of the genus Sphingomonas were found. In contrast to most plant sap-sucking hemipterans, the bacterial associates of O. urticae, M. pini, and S. gorodetskia are not harbored in specialized bacteriocytes, but are dispersed in the cells of different organs. Ultrastructural observations have shown that bacteria Wolbachia in O. urticae and M. pini, Sodalis in O. urticae, and Sphingomonas in S. gorodetskia are transovarially transmitted from mother to progeny.

Symbiotic microorganisms in Puto superbus (Leonardi, 1907) (Insecta, Hemiptera, Coccomorpha: Putoidae)

The scale insect Puto superbus (Putoidae) lives in mutualistic symbiotic association with bacteria. Molecular phylogenetic analyses have revealed that symbionts of P. superbus belong to the gammaproteobacterial genus Sodalis. In the adult females, symbionts occur both in the bacteriocytes constituting compact bacteriomes and in individual bacteriocytes, which are dispersed among ovarioles. The bacteriocytes also house a few small, rod-shaped Wolbachia bacteria in addition to the numerous large, elongated Sodalis-allied bacteria. The symbiotic microorganisms are transovarially transmitted from generation to generation. In adult females which have choriogenic oocytes in the ovarioles, the bacteriocytes gather around the basal part of the tropharium. Next, the entire bacteriocytes pass through the follicular epithelium surrounding the neck region of the ovariole and enter the space between oocyte and follicular epithelium (perivitelline space). In the perivitelline space, the bacteriocytes assemble extracellularly in the deep depression of the oolemma at the anterior pole of the oocyte, forming a "symbiont ball".

Bacteria belonging to the genus Burkholderia are obligatory symbionts of the eriococcids Acanthococcus aceris Signoret, 1875 and Gossyparia spuria (Modeer, 1778) (Insecta, Hemiptera, Coccoidea)

In the fat body cells of the scale insects, Gossyparia spuria and Acanthococcus aceris, numerous rod-shaped symbiotic bacteria occur. Molecular analyses have revealed that these microorganisms are closely related to the widely distributed bacterium Burkholderia. Ultrastructural observations have revealed that the bacteria are transovarially (vertically) transmitted from the mother to offspring. The microorganisms leave the fat body cells and invade ovarioles containing vitellogenic oocytes. They pass through the follicular epithelium in the neck region of the ovariole and enter the perivitelline space. Next, the symbionts infest the anterior region of the oocyte.

Thorax morphology of selected species of the genus Cacopsylla (Hemiptera, Psylloidea)

The paper concerns with characteristics of a thorax morphological structure Cacopsylla Ossiannilsson, 1970 species, referring to an analysis of five species classified in the past in three subgenera. The structure of the sternites, tergites and pleurites of all the parts of the thorax was studied by a scanning microscope. Descriptions of particular elements building up thorax plates, their shape, size and links as well as a course of all the clefts and sulcus are provided. The study of thorax morphology of Cacopsylla species suggests that the thorax morphology is relatively homogenous within a genus.