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EN
Cimicomorpha), the first evidence for the tribe Arachnocorini (the subfamily Nabinae), with reference to the Trinidad endemic, Arachnocoris trinitatus Bergroth, is provided. This is an attempt to gain a better insight into the evolution, systematics and within-family relationships of the family Nabidae. The studies were conducted using a number of cytogenetic techniques. The male karyotype (chromosome number and size; sex chromosome system; NOR location; C-heterochromatin amount, distribution and characterization in terms of the presence of AT-rich and GC-rich DNA), and male meiosis with particular emphasis on the behavior of the sex chromosomes in metaphase II are described. Also investigated are the male and female internal reproductive organs with special reference to the number of follicles in a testis and the number of ovarioles in an ovary. A. trinitatus was found to display a number of characters differentiating it from all hitherto studied nabid species placed in the tribe Nabini of the subfamily Nabinae, and in the tribe Prostemmatini of the subfamily Prostemmatinae. Among these characters are chromosome number 2n = 12 (10 + XY), the lowest within the family, nucleolus organizer regions (NORs) situated on the autosomes rather than on the sex chromosomes as is the case in other nabid species, and testes composed of 3 follicles but not of 7 as in other nabids. All the data obtained suggest many transformations during the evolution of A. trinitatus.
EN
The karyotype of the meadow spittlebug Philaenus spumarius (L.) was studied using conventional chromosome staining, C- and AgNOR- banding, and fluorescent CMA3- and DAPI- techniques. This is the first report on differential staining of the holocentric chromosomes of Auchenorrhyncha. The karyotype of Ph. spumarius includes 2n = 22 + XX/X0. The autosomal pair 1 is large and carries a gap in every homologue. After silver staining, NORs were revealed in both this chromosome pair and a middle-sized pair, most likely 6 or 7. In spermatocyte meiosis, the majority of bivalents formed one chiasma each. The bivalent 1 showed from 1 to 4 chiasmata, the value of 1 or 2 being prevalent. Two further bivalents also showed two chiasmata in some cells. After C-banding, terminal and interstitial dot-type C-heterochromatic blocks were revealed in the chromosomes. In 4 of 11 studied males, the autosomal pair 1 was polymorphic for an extra segment attached to one of the homologues. The segment consisted of both heterochromatic and euchromatic portions. No defined signals were observed in any chromosome treated with DAPI. After CMA3- staining, bright fluorescent signals were obtained in the NOR-bearing chromosomes, suggesting GC-rich DNA bound to the NORs.
EN
Meiotic karyotypes in males of 16 species (assigned to 9 genera and 7 subfamilies) of the family Psyllidae and 3 species (assigned to 3 genera of the subfamily Triozinae) of the family Triozidae are described for the first time. The first data on the genus Ligustrinia are presented. All the species were shown to exhibit the modal karyotype for psyllids, 2n = 24 + X, except Bactericera nigricornis and Arytainilla spartiophila, in which 2n = 24 + XY and 2n = 22 + X were found, respectively. The karyotype of Ctenarytaina eucalypti (Psyllidae, Spondyliaspidinae) was reinvestigated, and the karyotype 2n = 10 + X, characteristic of Spondyliaspidinae, was revealed. The karyotypes of Strophingia fallax, S. arborea, and Craspedolepta topicalis were studied using the C-banding technique.
EN
As a part of ongoing cytogenetic studies on the jewel-beetles (Buprestidae, Coleoptera) of Armenia, the male karyotypes and meiosis of nine species (5 genera, 4 tribes, 2 subfamilies) are described, figured and discussed. In Ovalisia nadezhdae Sem., Sphenoptera artemisiae Reitt., Coraebus rubi L., C. sinuatus Creutz., Meliboeus caucasicus Reitt., Agrilus angustulus Ill. Men., A. obscuricollis Kiesw., and A. araxenus Khnz. diploid chromosome numbers vary in a narrow range from 20 to 24. In Sph. glabrata Men. a high chromosome number of 2n=40 was discovered. All the species have a XY sex chromosome system, which is however of different types. The data available on the buprestid karyotypes and karyotype variation at different taxonomic levels within the family are discussed.
EN
Karyotypes (number and size of chromosomes, sex -determining system) and testis structure (number of testicular follicles) of 37 species belonging to 24 genera of the little studied fulgoroid families Cixiidae, Meenoplidae, Derbidae, Achilidae, Nogodinidae, Tropiduchidae and Flatidae are presented. For Meenoplidae, Nogodinidae and Tropiduchidae data on the testis structure have been obtained for the first time. The data available for Fulgoroidea as a whole are reviewed.
EN
The pattern of nucleolus attachment and C-heterochromatin distribution and molecular composition in the karyotypes of psocid species Psococerastis gibbosa (2n = 16+X), Blaste conspurcata (2n = 16+X) and Amphipsocus japonicus (2n = 14+neo-XY) were studied by C-banding, silver impregnation and sequence specific fluorochromes CMA3 and DAPI. Every species was found to have a single nucleolus in male meiosis. In P. gibbosa the nucleolus is attached to an autosomal bivalent; in B. conspurcata to the X-chromosome; in A. japonicus to the neo-XY bivalent. The species show a rather small amount of constitutive heterochromatin, C-blocks demonstrating telomeric localization with rare exceptions. P. gibbosa is characterized by a polymorphism for C-blocks occurrence and distribution. In the autosomes of this species, C-heterochromatin consists of AT-rich DNA except for the nucleolus organizing region, which is also GC-rich; the X-chromosome shows both AT- and GC-rich clusters. In A. japonicus and B. conspurcata, C-heterochromatin of the autosomes and sex chromosomes consists of both GC-rich and AT-rich DNA clusters, which are largely co-localized.
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