Comparative Cytogenetics最新文献

{"title":"Chromosomes of parasitic wasps of the superfamily Chalcidoidea (Hymenoptera): An overview.","authors":"Vladimir E Gokhman","doi":"10.3897/CompCytogen.v14i3.56535","DOIUrl":"10.3897/CompCytogen.v14i3.56535","url":null,"abstract":"<p><p>An overview of the current knowledge of chromosome sets of the parasitoid superfamily Chalcidoidea is given. Karyotypes of approximately 240 members of this group, i.e. just above one percent of described species, are studied up to now. Techniques for obtaining and analyzing preparations of chalcid chromosomes are outlined, including the so-called \"traditional\" and \"modern\" methods of differential staining as well as fluorescence in situ hybridization (FISH). Among the Chalcidoidea, the haploid chromosome number can vary from n = 3 to n = 11, with a clear mode at n = 6 and a second local maximum at n = 10. In this group, most chromosomes are either metacentric or submetacentric, but acrocentrics and/or subtelocentrics also can predominate, especially within karyotypes of certain Chalcidoidea with higher chromosome numbers. The following main types of chromosomal mutations are characteristic of chalcid karyotypes: inversions, fusions, translocations, polyploidy, aneuploidy and B chromosome variation. Although karyotype evolution of this superfamily was mainly studied using phylogenetic reconstructions based on morphological and/or molecular characters, chromosomal synapomorphies of certain groups were also revealed. Taxonomic implications of karyotypic features of the Chalcidoidea are apparently the most important at the species level, especially among cryptic taxa.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 3","pages":"399-416"},"PeriodicalIF":1.0,"publicationDate":"2020-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9849058/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10746540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The epigenetic regulation of centromeres and telomeres in plants and animals.","authors":"Magdalena Achrem,&nbsp;Izabela Szućko,&nbsp;Anna Kalinka","doi":"10.3897/CompCytogen.v14i2.51895","DOIUrl":"https://doi.org/10.3897/CompCytogen.v14i2.51895","url":null,"abstract":"<p><p>The centromere is a chromosomal region where the kinetochore is formed, which is the attachment point of spindle fibers. Thus, it is responsible for the correct chromosome segregation during cell division. Telomeres protect chromosome ends against enzymatic degradation and fusions, and localize chromosomes in the cell nucleus. For this reason, centromeres and telomeres are parts of each linear chromosome that are necessary for their proper functioning. More and more research results show that the identity and functions of these chromosomal regions are epigenetically determined. Telomeres and centromeres are both usually described as highly condensed heterochromatin regions. However, the epigenetic nature of centromeres and telomeres is unique, as epigenetic modifications characteristic of both eu- and heterochromatin have been found in these areas. This specificity allows for the proper functioning of both regions, thereby affecting chromosome homeostasis. This review focuses on demonstrating the role of epigenetic mechanisms in the functioning of centromeres and telomeres in plants and animals.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 2","pages":"265-311"},"PeriodicalIF":1.0,"publicationDate":"2020-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7360632/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38220043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative molecular cytogenetic characterization of five wild <i>Vigna</i> species (Fabaceae).","authors":"Chao-Wen She,&nbsp;Ying Mao,&nbsp;Xiang-Hui Jiang,&nbsp;Chun-Ping He","doi":"10.3897/CompCytogen.v14i2.51154","DOIUrl":"https://doi.org/10.3897/CompCytogen.v14i2.51154","url":null,"abstract":"<p><p>To extend our knowledge on karyotype variation of the genus <i>Vigna</i> Savi, 1824, the chromosomal organization of rRNA genes and fluorochrome banding patterns of five wild <i>Vigna</i> species were studied. Sequential combined PI (propidium iodide) and DAPI (4',6-diamidino-2-phenylindole) (CPD) staining and fluorescence <i>in situ</i> hybridization (FISH) with 5S and 45S rDNA probes were used to analyze the karyotypes of <i>V. luteola</i> (Jacquin, 1771) Bentham, 1959, <i>V. vexillata</i> (Linnaeus, 1753) A. Richard, 1845, <i>V. minima</i> (Roxburgh, 1832) Ohwi & H. Ohashi, 1969, <i>V. trilobata</i> (Linnaeus, 1753) Verdcourt, 1968, and <i>V. caracalla</i> (Linnaeus, 1753) Verdcourt,1970. For further phylogenetic analysis, genomic <i>in situ</i> hybridization (GISH) with the genomic DNA of <i>V. umbellata</i> (Thunberg, 1794) Ohwi & H.Ohashi, 1969 onto the chromosomes of five wild <i>Vigna</i> species was also performed. Detailed karyotypes were established for the first time using chromosome measurements, fluorochrome bands, and rDNA-FISH signals. All species had chromosome number 2n = 2x = 22, and symmetrical karyotypes that composed of only metacentric or metacentric and submetacentric chromosomes. CPD staining revealed all 45S rDNA sites in the five species analyzed, (peri)centromeric GC-rich heterochromatin in <i>V. luteola</i>, <i>V. trilobata</i> and <i>V. caracalla</i>, interstitial GC-rich and pericentromeric AT-rich heterochromatin in <i>V. caracalla</i>. rDNA-FISH revealed two 5S loci in <i>V. caracalla</i> and one 5S locus in the other four species; one 45S locus in <i>V. luteola</i> and <i>V. caracalla</i>, two 45S loci in <i>V. vexillata</i> and <i>V. trilobata</i>, and five 45S loci in <i>V. minima</i>. The karyotypes of the studied species could be clearly distinguished by the karyotypic parameters, and the patterns of the fluorochrome bands and the rDNA sites, which revealed high interspecific variation among the five species. The <i>V. umbellata</i> genomic DNA probe produced weak signals in all proximal regions of <i>V. luteola</i> and all (peri)centromeric regions of <i>V. trilobata</i>. The combined data demonstrate that distinct genome differentiation has occurred among the five species during evolution. The phylogenetic relationships between the five wild species and related cultivated species of <i>Vigna</i> are discussed based on our present and previous molecular cytogenetic data.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 2","pages":"243-264"},"PeriodicalIF":1.0,"publicationDate":"2020-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7334243/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38168712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cytogenetic markers as a tool for characterization of hybrids of <i>Astyanax</i> Baird & Girard, 1854 and <i>Hyphessobrycon</i> Eigenmann, 1907.","authors":"Caio Augusto Gomes Goes,&nbsp;Sandro Natal Daniel,&nbsp;Lucas Henrique Piva,&nbsp;George Shigueki Yasui,&nbsp;Roberto Ferreira Artoni,&nbsp;Diogo Teruo Hashimoto,&nbsp;Fausto Foresti,&nbsp;Fábio Porto-Foresti","doi":"10.3897/CompCytogen.v14i2.49513","DOIUrl":"https://doi.org/10.3897/CompCytogen.v14i2.49513","url":null,"abstract":"<p><p><i>Astyanax</i> Baird et Girard, 1854, is one of the largest genera in the family Characidae and comprises 177 valid species. This genus has been the focus of cytogenetic studies primarily owing to the presence of B chromosomes and high karyotypic diversity among different populations. The intense genetic variability in <i>Astyanax</i> is one of the factors responsible for the occurrence of species complexes, which are groups (1) with certain difficulties in establishing common genetic pools or (2) belonging to different cryptic species. To evaluate cytogenetic marker inheritance and the possibility of the identification of these hybrids, this study aimed to describe cytogenetic hybrids from three strains of species of the genera <i>Astyanax</i> and <i>Hyphessobrycon</i> Eigenmann, 1908. <i>A. lacustris</i> Lütken, 1875, <i>A. schubarti</i> Britski, 1964, <i>A. fasciatus</i> Cuvier, 1819, and <i>H. anisitsi</i> Eigenmann, 1907 were used to generate three hybrid lineages. The diploid number, heterochromatin sites, and ribosomal genes (18S and 5S rDNA) of the parental strains and the hybrids were analyzed. The results indicated that the three hybrid lineages had cytogenetic markers of both parents, presenting Mendelian inheritance. However, differences in distribution of heterochromatic blocks were observed between the hybrids and the parent strains. Our results allowed the identification of the hybrid strains based on the cytogenetic markers applied, reinforcing the efficiency of cytogenetic markers as tools for identification and indicating that such events may increase the karyotypic diversity in the genera <i>Astyanax</i> and <i>Hyphessobrycon</i>.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 2","pages":"231-242"},"PeriodicalIF":1.0,"publicationDate":"2020-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7270076/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38043541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Induction and evaluation of colchitetraploids of two species of <i>Tinospora</i> Miers, 1851.","authors":"Rakesh Kr Thakur,&nbsp;Vijay Rani Rajpal,&nbsp;Satyawada Rama Rao,&nbsp;Apekshita Singh,&nbsp;Lata Joshi,&nbsp;Pankaj Kaushal,&nbsp;Soom Nath Raina","doi":"10.3897/CompCytogen.v14i2.33394","DOIUrl":"https://doi.org/10.3897/CompCytogen.v14i2.33394","url":null,"abstract":"<p><p>Autotetraploidy, both natural and/or induced, has potential for genetic improvement of various crop species including that of medicinal importance. <i>Tinospora cordifolia</i> (Willdenow, 1806) Miers, 1851 ex Hooker et Thomson, 1855 and <i>T. sinensis</i> (Loureiro, 1790) Merrill, 1934 are two diploid species, which are dioecious, deciduous and climbing shrubs with high medicinal importance. Among the three methods used for induction of polyploidy by colchicine treatment, it was cotton swab method which successfully induced the polyploidy in both species. The morphological and cytogenetical features of the synthetic tetraploids were compared with their diploid counterparts. The tetraploids were morphologically distinct from diploid plants. They exhibited larger organs, such as stem, leaves, inflorescence, fruits, flowers and seeds. The tetraploids were characterized by the presence of low quadrivalent frequency and high bivalent average. Unequal distribution of chromosomes at anaphase I was found in 60% cells. The present study provides important information on the superiority of autotetraploids as compared to diploid counterparts in both species.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 2","pages":"211-229"},"PeriodicalIF":1.0,"publicationDate":"2020-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7253504/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"38023153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Karyotype and putative chromosomal inversion suggested by integration of cytogenetic and molecular data of the fungus-farming ant <i>Mycetomoellerius iheringi</i> Emery, 1888.","authors":"Ricardo Micolino,&nbsp;Maykon Passos Cristiano,&nbsp;Danon Clemes Cardoso","doi":"10.3897/CompCytogen.v14i2.49846","DOIUrl":"https://doi.org/10.3897/CompCytogen.v14i2.49846","url":null,"abstract":"<p><p>Comparative cytogenetic analyses are being increasingly used to collect information on species evolution, for example, diversification of closely related lineages and identification of morphologically indistinguishable species or lineages. Here, we have described the karyotype of the fungus-farming ant <i>Mycetomoellerius iheringi</i> Emery, 1888 and investigated its evolutionary relationships on the basis of molecular and cytogenetic data. The <i>M. iheringi</i> karyotype consists of 2n = 20 chromosomes (2K = 18M + 2SM). We also demonstrated that this species has the classical insect TTAGG telomere organization. Phylogenetic reconstruction showed that <i>M. iheringi</i> is phylogenetically closer to <i>M. cirratus</i> Mayhé-Nunes & Brandão, 2005 and <i>M. kempfi</i> Fowler, 1982. We compared <i>M. iheringi</i> with other congeneric species such as <i>M. holmgreni</i> Wheeler, 1925 and inferred that <i>M. iheringi</i> probably underwent a major pericentric inversion in one of its largest chromosomes, making it submetacentric. We discussed our results in the light of the phylogenetic relationships and chromosomal evolution.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 2","pages":"197-210"},"PeriodicalIF":1.0,"publicationDate":"2020-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7225177/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37957425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cloning and preliminary verification of telomere-associated sequences in upland cotton.","authors":"Yuling Liu,&nbsp;Zhen Liu,&nbsp;Yangyang Wei,&nbsp;Yanjun Wang,&nbsp;Jiaran Shuang,&nbsp;Renhai Peng","doi":"10.3897/CompCytogen.v14i2.49391","DOIUrl":"https://doi.org/10.3897/CompCytogen.v14i2.49391","url":null,"abstract":"<p><p>Telomeres are structures enriched in repetitive sequences at the end of chromosomes. In this study, using the telomere primer AA(CCCTAAA)₃CCC for the single primer PCR, two DNA sequences were obtained from <i>Gossypium hirsutum</i> (Linnaeus, 1753) accession (acc.) TM-1. Sequence analysis showed that the two obtained sequences were all rich in A/T base, which was consistent with the characteristic of the telomere-associated sequence (TAS). They were designated as GhTAS1 and GhTAS2 respectively. GhTAS1 is 489 bp long, with 57.6% of A/T, and GhTAS2 is 539 bp long, with 63.9% of A/T. Fluorescence <i>in situ</i> hybridization results showed that both of the cloned TASs were located at the ends of the partial chromosomes of <i>G. hirsutum</i>, with the strong signals, which further confirmed that GhTAS1 and GhTAS2 were telomere-associated sequences including highly tandemly repetitive sequences. Results of blast against the assembled genome of <i>G. hirsutum</i> showed that GhTAS sequences may be missed on some assembled chromosomes. The results provide important evidence for the evaluation of the integrity of assembled chromosome end sequences, and will also contribute to the further perfection of the draft genomes of cotton.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 2","pages":"183-195"},"PeriodicalIF":1.0,"publicationDate":"2020-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7154043/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37849621","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Patterns of chromosomal variation in Mexican species of <i>Aeschynomene</i> (Fabaceae, Papilionoideae) and their evolutionary and taxonomic implications.","authors":"Fernando Tapia-Pastrana,&nbsp;Alfonso Delgado-Salinas,&nbsp;Javier Caballero","doi":"10.3897/CompCytogen.v14i1.47264","DOIUrl":"https://doi.org/10.3897/CompCytogen.v14i1.47264","url":null,"abstract":"<p><p>A cytogenetic analysis of sixteen taxa of the genus <i>Aeschynomene</i> Linnaeus, 1753, which includes species belonging to both subgenera <i>Aeschynomene</i> (Léonard, 1954) and <i>Ochopodium</i> (Vogel, 1838) J. Léonard, 1954, was performed. All studied species had the same chromosome number (2n = 20) but exhibited karyotype diversity originating in different combinations of metacentric, submetacentric and subtelocentric chromosomes, chromosome size and number of SAT chromosomes. The plasticity of the genomes included the observation in a taxon belonging to the subgenus Aeschynomene of an isolated spherical structure similar in appearance to the extra chromosomal circular DNA observed in other plant genera. By superimposing the karyotypes in a recent phylogenetic tree, a correspondence between morphology, phylogeny and cytogenetic characteristics of the taxa included in the subgenus Aeschynomene is observed. Unlike subgenus Aeschynomene, the species of <i>Ochopodium</i> exhibit notable karyotype heterogeneity. However the limited cytogenetic information recorded prevents us from supporting the proposal of their taxonomic separation and raise it to the genus category. It is shown that karyotype information is useful in the taxonomic delimitation of <i>Aeschynomene</i> and that the diversity in the diploid level preceded the hybridization/polyploidization demonstrated in the genus. The systematic implications of our results and their value can be extended to other Dalbergieae genera as knowledge about the chromosomal structure and its evolution increases.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 1","pages":"157-182"},"PeriodicalIF":1.0,"publicationDate":"2020-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7080853/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37766912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New data on karyotype, spermatogenesis and ovarian trophocyte ploidy in three aquatic bug species of the families Naucoridae, Notonectidae, and Belostomatidae (Nepomorpha, Heteroptera).","authors":"Desislava Stoianova,&nbsp;Nikolay Simov,&nbsp;Manh Quang Vu,&nbsp;Duc Minh Nguyen,&nbsp;Snejana Grozeva","doi":"10.3897/CompCytogen.v14i1.48709","DOIUrl":"https://doi.org/10.3897/CompCytogen.v14i1.48709","url":null,"abstract":"<p><p>We report the karyotype, some aspects of spermatogenesis, and ovarian trophocytes ploidy in three aquatic bug species: <i>Ilyocoris cimicoides</i> (Linnaeus, 1758), <i>Notonecta glauca</i> Linnaeus, 1758, and <i>Diplonychus rusticus</i> Fabricius, 1871 from previously unexplored regions - South Europe (Bulgaria) and Southeast Asia (Vietnam). Our results add considerable support for the published karyotype data for these species. In <i>I. cimicoides</i>, we observed achiasmate male meiosis - the first report of achiasmy for the family Naucoridae. More comprehensive cytogenetic studies in other species of the Naucoridae are required to elucidate the role of achiasmy as a character in the systematics of the family. Our observations on the association between phases of spermatogenesis and developmental stages in <i>I. cimicoides</i> and <i>N. glauca</i> differ from the previously published data. In these species, we assume that the spermatogenesis phases are not strongly associated with certain developmental stages. For further cytogenetic studies (on the Balkan Peninsula), we recommend July as the most appropriate month for collection of <i>I. cimicoides</i> and <i>N. glauca</i>. In the ovaries of both species, we studied the level of ploidy in metaphase and interphase trophocytes. In <i>I. cimicoides</i>, diploid and tetraploid metaphase trophocytes were found. Heteropycnotic elements, observed in interphase trophocytes of this species, represented the X chromosomes. It allowed us to determine the trophocytes ploidy at interphase (2n was repeated up to 16 times). The situation with <i>N. glauca</i> was different. The metaphase trophocytes were diploid and we were not able to determine the ploidy of interphase trophocytes since such conspicuous heteropycnotic elements were not found. The scarce data available suggest a tendency for a low level of trophocyte ploidy in the basal infraorders (Nepomorpha and Gerromorpha) and for a high level in the more advanced Pentatomomorpha. Data about this character in species from other infraorders are needed to confirm that tendency.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 1","pages":"139-156"},"PeriodicalIF":1.0,"publicationDate":"2020-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7067897/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37756863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cytogenetics of entelegyne spiders (Arachnida, Araneae) from southern Africa.","authors":"František Šťáhlavský, Martin Forman, Pavel Just, Filip Denič, Charles R Haddad, Vera Opatova","doi":"10.3897/CompCytogen.v14i1.48667","DOIUrl":"10.3897/CompCytogen.v14i1.48667","url":null,"abstract":"<p><p>Spiders represent one of the most studied arachnid orders. They are particularly intriguing from a cytogenetic point of view, due to their complex and dynamic sex chromosome determination systems. Despite intensive research on this group, cytogenetic data from African spiders are still mostly lacking. In this study, we describe the karyotypes of 38 species of spiders belonging to 16 entelegyne families from South Africa and Namibia. In the majority of analysed families, the observed chromosome numbers and morphology (mainly acrocentric) did not deviate from the family-level cytogenetic characteristics based on material from other continents: Tetragnathidae (2n♂ = 24), Ctenidae and Oxyopidae (2n♂ = 28), Sparassidae (2n♂ = 42), Gnaphosidae, Trachelidae and Trochanteriidae (2n♂ = 22), and Salticidae (2n♂ = 28). On the other hand, we identified interspecific variability within Hersiliidae (2n♂ = 33 and 35), Oecobiidae (2n♂ = 19 and 25), Selenopidae (2n♂ = 26 and 29) and Theridiidae (2n♂ = 21 and 22). We examined the karyotypes of Ammoxenidae and Gallieniellidae for the first time. Their diploid counts (2n♂ = 22) correspond to the superfamily Gnaphosoidea and support their placement in this lineage. On the other hand, the karyotypes of Prodidominae (2n♂ = 28 and 29) contrast with all other Gnaphosoidea. Similarly, the unusually high diploid number in <i>Borboropactus</i> sp. (2n♂ = 28) within the otherwise cytogenetically uniform family Thomisidae (mainly 2n♂ = 21-24) supports molecular data suggesting a basal position of the genus in the family. The implementation of FISH methods for visualisation of rDNA clusters facilitated the detection of complex dynamics of numbers of these loci. We identified up to five loci of the 18S rDNA clusters in our samples. Three different sex chromosome systems (X0, X₁X₂0 and X₁X₂X₃0) were also detected among the studied taxa.</p>","PeriodicalId":50656,"journal":{"name":"Comparative Cytogenetics","volume":"14 1","pages":"107-138"},"PeriodicalIF":1.0,"publicationDate":"2020-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7066264/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"37756862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}