In terms of cytogenetics, entelegyne araneomorphs are the best studied clade of spiders. The typical karyotype of entelegyne males consists of acrocentric chromosomes, including 2 non-homologous X chromosomes. The present study is focused on the karyotype, nucleolus organising regions (NORs) and sex chromosome behaviour during meiosis of the entelegyne Wadicosa fidelis (Lycosidae). Preparations stained by Giemsa were used to study karyotype and meiosis. NORs were visualised by silver staining and fluorescence in situ hybridisation with 18S rDNA probe. The male karyotype consists of 28 acrocentric elements, including 2 X chromosomes. In contrast to the majority of other spiders, the male sex chromosomes pair during the major part of meiosis. Following an initial period of parallel pairing, the attachment of male sex chromosomes is restricted to centromeric areas and continues until metaphase II. Our study revealed an enormous number of NORs in the population from Galilee and indicates a considerable variability of NOR numbers in this population. The distal regions of 9 or 10 autosomal pairs contain NORs. The obtained data indicate the rapid spread of NORs in the karyotype of W. fidelis, which was presumably caused by ectopic recombinations and subsequent hybridisations of individuals with different NOR genotypes that produced heterozygotes.

Adams SP, Leitch IJ, Bennett MD, Chase MW, Leitch AR: Ribosomal DNA evolution and phylogeny in Aloe (Asphodelaceae). Am J Bot 87:1578-1583 (2000).
Araújo D, Cella DM, Brescovit AD: Cytogenetic analysis of the neotropical spider Nephilengys cruentata (Araneomorphae, Tetragnathidae): standard staining, NORs, C-bands and base-specific fluorochromes. Braz J Biol 65:193-202 (2005).
Araújo D, Schneider MC, Paula-Neto E, Cella DM: The spider cytogenetic database 1.0. (2012a).
Araújo D, Schneider MC, Paula-Neto E, Cella DM: Sex chromosomes and meiosis in spiders: a review, in Swan A (ed): Meiosis - Molecular Mechanisms and Cytogenetic Diversity (InTech, Rijeka 2012b).
Benavente R, Wettstein R: An ultrastructural cytogenetic study on the evolution of sex chromosomes during spermatogenesis of Lycosa malitiosa (Arachnida). Chromosoma 64:255-277 (1977).
Bole-Gowda BN: The chromosome study in the spermatogenesis of two lynx-spiders (Oxyopidae). Proc Zool Soc Bengal 3:95-107 (1950).
Bole-Gowda BN: Studies on the chromosomes and the sex-determining mechanism in four hunting spiders (Sparassidae). Proc Zool Soc Bengal 5:51-70 (1952).
Cabral-de-Mello DC, Oliveira SG, de Moura RC, Martins C: Chromosomal organization of the 18S and 5S rRNAs and histone H3 genes in Scarabaeinae coleopterans: insights into the evolutionary dynamics of multigene families and heterochromatin. BMC Genetics 12:88 (2011).
Cabrero J, Camacho JPM: Location and expression of ribosomal RNA genes in grasshoppers: abundance of silent and cryptic loci. Chromosome Res 16:595-607 (2008).
Chemisquy MA, Rodríguez-Gil SG, Scioscia CL, Mola LM: Cytogenetic studies of three Lycosidae species from Argentina (Arachnida, Araneae). Genet Mol Biol 31:857-867 (2008).
Coddington JA, Levi HW: Systematics and evolution of spiders (Araneae). Annu Rev Ecol Syst 22:565-592 (1991).
Dobigny G, Ozouf-Costaz C, Bonillo C, Volobouev V: Evolution of rDNA gene clusters and telomeric repeats during explosive genome repattering in Taterillus X (Rodentia, Gerbilinae). Cytogenet Genome Res 103:94-103 (2003).
Dolejš P, Kořínková T, Musilová J, Opatová V, Kubcová L, et al: Karyotypes of central European spiders of the genera Arctosa, Tricca, and Xerolycosa (Araneae: Lycosidae). Eur J Entomol 108:1-16 (2011).
Fuková I, Nguyen P, Marec F: Codling moth cytogenetics: karyotype, chromosomal location of rDNA, and molecular differentiation of sex chromosomes. Genome 48:1083-1092 (2005).
Gunn SJ, Hilburn LR: Differential staining of tick chromosomes: techniques for C-banding and silver-staining and karyology of Rhipicephalus sanguineus (Latreille). J Parasitol 75:239-245 (1989).
Hackman W: Chromosomenstudien an Araneen mit besonderer Berücksichtigung der Geschlechtschromosomen. Acta Zool Fennica 54:1-101 (1948).
Hill CA, Guerrero FD, Van Zee JP, Geraci N, Walling JG, Stuart JJ: The position of repetitive DNA sequence in the southern cattle tick genome permits chromosome identification. Chromosome Res 17:77-89 (2009).
Král J: Evolution of multiple sex chromosomes in the spider genus Malthonica (Araneae: Agelenidae) indicates unique structure of the spider sex chromosome systems. Chromosome Res 15:863-879 (2007).
Král J, Musilová J, Šťáhlavský F, Řezáč M, Akan Z, et al: Evolution of the karyotype and sex chromosome systems in basal clades of araneomorph spiders (Araneae: Araneomorphae). Chromosome Res 14:859-880 (2006).
Král J, Kováč Ľ, Šťáhlavský F, Lonský P, Ľuptáčik P: The first karyotype study in palpigrades, a primitive order of arachnids (Arachnida: Palpigradi). Genetica 134:79-87 (2008).
Král J, Kořínková T, Forman M, Krkavcová L: Insights into the meiotic behavior and evolution of multiple sex chromosome systems in spiders. Cytogenet Genome Res 133:43-66 (2011).
Lourenço LB, Recco-Pimentel SM, Cardoso AJ: Polymorphism of the nucleolus organizer regions (NORs) in Physalaemus petersi (Amphibia, Anura, Leptodactylidae) detected by silver staining and fluorescence in situ hybridization. Chromosome Res 6:621-628 (1998).
Luo R, Wang C, Zhang D: Variations of 18S rDNA loci among six populations of Paeonia obovata Maxim. (Paeoniaceae) revealed by fluorescence in situ hybridization. J Integr Plant Biol 48:497-502 (2006).
Meyer JM, Kurtti TJ, Van Zee JP, Hill CA: Genome organization of major tandem repeats in the hard tick, Ixodes scapularis. Chromosome Res 18:357-370 (2010).
Miller DA, Dew V, Tantravahi R, Miller O: Supression of human nucleolar organizer activity in mouse human somatic hybrid cells. Exp Cell Res 101:235-243 (1976).
Mittal OP: Karyological studies on the Indian spiders VIII. Chromosomes in the male germ cells of three species of the genus Oxyopes (family Oxyopidae). Microscope (London) 18:313-318 (1970).
Nguyen P, Sahara K, Yoshido A, Marec F: Evolutionary dynamics of rDNA clusters on chromosomes of moths and butterflies (Lepidoptera). Genetica 138:343-354 (2010).
Oliveira RM, Jesus AC, Brescovit AD, Cella DM: Chromosomes of Crossopriza lyoni (Blackwall 1867), intraindividual numerical chromosome variation in Physocyclus globosus (Taczanowski 1874), and the distribution pattern of NORs (Araneomorphae, Haplogynae, Pholcidae). J Arachnol 35:293-306 (2007).
Paula-Neto E: Nephila clavipes e Nephila sexpunctata (Araneae, Araneomorphae, Nephilidae): cariótipo, heterocromatina constitutiva e região organizadora de nucléolo. Thesis, Universidade Estadual Paulista, Instituto de Biociências de Rio Claro. Rio Claro, Brazil (2011).
Pekár S, Král J: A comparative study of the biology and karyotypes of two central European zodariid spiders (Araneae, Zodariidae). J Arachnol 29:345-353 (2001).
Platnick NI: The World Spider Catalog, version 13.5. American Museum of Natural History. (2013).
Postiglioni A, Brum-Zorrilla N: Karyological studies on Uruguayan spiders II. Sex chromosomes in spiders of the genus Lycosa (Araneae-Lycosidae). Genetica 56:47-53 (1981).
Rodríguez-Gil SG, Merani MS, Scioscia CL, Mola LM: Cytogenetics in three species of Polybetes Simon 1897 from Argentina (Araneae, Sparassidae) I. Karyotype and chromosome banding pattern. J Arachnol 35:227-237 (2007).
Rowell DM: Chromosomal fusion and meiotic behaviour in Delena cancerides (Araneae: Sparassidae). I. Chromosome pairing and X-chromosome segregation. Genome 34:561-566 (1991).
Schneider MC, Cella DM: Karyotype conservation in 2 populations of the parthenogenetic scorpion Tityus serrulatus (Buthidae): rDNA and its associated heterochromatin are concentrated on only one chromosome. J Hered 101:491-496 (2010).
Schneider MC, Zacaro AA, Oliveira RM, Gnaspini P, Cella DM: Conventional and ultrastructural analyses of the chromosomes of Discocyrtus pectinifemur (Opiliones, Laniatores, Gonyleptidae). J Zool Syst Evol Res 47:203-207 (2008).
Srivastava MD, Shukla S: Chromosome number and sex determining mechanism in forty-seven species of Indian spiders. Chromosome Inf Serv 41:23-26 (1986).
Stávale LM, Schneider MC, Araújo D, Brescovit AD, Cella DM: Chromosomes of Theridiidae spiders (Entelegynae): interspecific karyotype diversity in Argyrodes and diploid number intraspecific variability in Nesticodes rufipes. Genet Mol Biol 33:663-668 (2010).
Stávale LM, Schneider MC, Brescovit AD, Cella DM: Chromosomal characteristics and karyotype evolution of Oxyopidae spiders (Araneae, Entelegynae). Genet Mol Res 10:752-763 (2011).
Suzuki S: Cytological studies in spiders. III. Studies on the chromosomes of fifty-seven species of spiders belonging to seventeen families, with general considerations on chromosomal evolution. J Sci Hiroshima Univ B 15:23-136 (1954).
Vítková M, Král J, Traut W, Zrzavý J, Marec F: The evolutionary origin of insect telomeric repeats, (TTAGG)n. Chromosome Res 13:145-156 (2005).
White MJD: Animal Cytology and Evolution (Cambridge University Press, Cambridge 1973).
Wise D: An electron microscope study of the karyotypes of two wolf spiders. Can J Genet Cytol 25:161-168 (1983).
Zhao Y, Ayoub NA, Hayashi CY: Chromosome mapping of dragline silk genes in the genomes of widow spiders (Araneae, Theridiidae). PLoS One 5:e12804 (2010).
Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.