We analyzed the distribution of 2 repetitive DNAs, i.e. ribosomal DNA (rDNA) and a satellite DNA (satDNA), on the B chromosomes found in 17 natural populations of the grasshopper Eyprepocnemis ploransplorans sampled around the western Mediterranean region, including the Iberian Peninsula, Balearic Islands, Sicily, and Tunisia. Based on the amount of these repetitive DNAs, 4 types of B variants were found: B₁, showing an equal or higher amount of rDNA than satDNA, and 3 other variants, B₂, B₂₄ and B₅, bearing a higher amount of satDNA than rDNA. The variants B₁ and B₂ varied in size among populations: B₁ was about half the size of the X chromosome in Balearic Islands, but two-thirds of the X in Iberian populations at Alicante, Murcia and Albacete provinces. Likewise, B₂ was about one-third the size of the X chromosome in populations from the Granada province but half the size of the X in the populations collected at Málaga province. The widespread geographical distribution of the B₁ variant makes it the best candidate for being the ancestor B chromosome in the whole western Mediterranean region.

Aphids (Hemiptera: Aphididae) can harbor two types of bacterial symbionts. In addition to the obligate endosymbiont Buchnera aphidicola Munson, Baumann and Kinsey 1991 (Enterobacteriales: Enterobacteriaceae), several facultative symbiotic bacteria, called secondary (S) symbionts, have been identified among many important pest aphid species. To determine interpopulational diversity of S-symbionts, we carried out a survey in a total of 18 populations of six aphid species collected from six localities in Tunisia, by performing a diagnostic polymerase chain reaction analysis of partial 16S-23S rRNA operon sequences. While 61.7% of individuals contained only Buchnera, three S-symbionts were found at different frequencies. Arsenophonus sp. Gherna et al. 1991 (Enterobacteriales: Enterobacteriaceae) was found in all species under study except for Acyrtosiphon pisum (Harris 1776) (Aphidinae: Macrosiphini); Serratia symbiotica Moran et al. 2005 (Enterobacteriales: Enterobacteriaceae) was present in all analyzed individuals of A. pisum but only sporadically in Aphis spiraecola (Patch 1914) (Aphidinae: Aphidini) and Hyalopterus amygdali (Blanchard 1840) (Aphidinae: Aphidini), while Hamiltonella defensa Moran et al. 2005 (Enterobacteriales: Enterobacteriaceae) was found in all analyzed individuals of one population of Aphis gossypii (Glover 1877) (Aphidinae: Aphidini) and sporadically in two populations of Hyalopterus. The lysogenic bacteriophage APSE-1 (A. pisum secondary endosymbiont, type 1) was detected in the three populations infected with H. defensa. This bacteriophage has been associated with moderate protection against braconid parasitoids in pea aphids. The high prevalence of Arsenophonus sp. in our samples is in accordance with previous studies indicating that, among gammaproteobacteria, this genus is one of the most widespread insect facultative symbionts.

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Inventory of ornamental plant mealybugs (Hemiptera Pseudococcidae) in Tunisia: species, host plants and distribution.In recent years, mealybugs (Hemiptera, Pseudococcidae) have become an important pest of ornamental plant in Tunisia due to their accident introduction and invasiveness. Awareness, early knowledge of invasive species, their host plant and geographical distribution could help to implement control methods which minimize the economic losses caused by them. A survey was conducted during 2013-2018 period to identify the mealybug species on ornamental plant, their host plant and document their geographic and periodic distribution. Seven species belonging to five genera were identified: Maconellicoccus hirsutus Green, Phenacoccus peruvianus Granara de Willink, Phenacoccus madeirensis Green, Planococcus vovae Nassonov, Planococcus citri Risso, Ferrisia virgata Cockerelland Pseudococcus longispinus Targioni-Tozzetti. M. hirsutuswas the most abundant mealybug and found in twenty-one sites on Hibiscus rosa-sinensis and Hibiscus mutabilis. P. peruvianus was the most polyphagous specie found on five host plants belonging to four families in eleven sites. P. citri was the single specie observed during wet season, therefore, all the rest species were found during dry season (summer, beginning autumn). These finding provide primary baseline knowledge of the mealybug fauna on ornamental plant in Tunisia and contribute information for use in the development of sustainable ornamental pest management strategies in the country.

In September 2016 and 2017, Ferrisia virgata Cockerell (Hemiptera: Pseudococcidae), the striped mealybug, was collected on Lantana camara (Verbenaceae) in Khezama City (Governorate Sousse, Tunisia). The mealybug was observed on leaves and shoots and also on the flowers. This is the first record of F. virgata in Tunisia and in North Africa. Brief information about its worldwide distribution and biology is presented.