biostudies-literatureUnknown19de Lima JF<i>Bothriurus</i> Peters, 1861 is one of the most diverse genera within the family Bothriuridae. However, to date, only five species have been analyzed using a cytogenetic approach. In this study, for the first time, two populations of <i>Bothriurus asper</i> Pocock, 1893 and nine populations of <i>Bothriurus rochai</i> Mello-Leitão, 1932, two species from northeastern Brazil, were analyzed with respect to diploid number, chromosomal behavior during meiosis, and the localization of heterochromatin and nucleolus organizer regions (NORs). For <i>B. asper</i>, a diploid number of 2n = 30 was recorded in geographically distant populations, whereas <i>B. rochai</i> exhibited intraspecific variation in diploid number (2n = 16 and 2n = 18), representing the lowest diploid numbers ever reported foComparative cytogenetics189-208https://www.ebi.ac.uk/biostudies/studies/S-EPMC12635637biostudies-literatureComparative cytogenetics among populations of two <i>Bothriurus</i> species (Scorpiones, Bothriuridae).PMC12635637de Lima JFCarvalho LSPinto-da-Rocha RSchneider MCfalseComparative cytogenetics among populations of two <i>Bothriurus</i> species (Scorpiones, Bothriuridae).<i>Bothriurus</i> Peters, 1861 is one of the most diverse genera within the family Bothriuridae. However, to date, only five species have been analyzed using a cytogenetic approach. In this study, for the first time, two populations of <i>Bothriurus asper</i> Pocock, 1893 and nine populations of <i>Bothriurus rochai</i> Mello-Leitão, 1932, two species from northeastern Brazil, were analyzed with respect to diploid number, chromosomal behavior during meiosis, and the localization of heterochromatin and nucleolus organizer regions (NORs). For <i>B. asper</i>, a diploid number of 2n = 30 was recorded in geographically distant populations, whereas <i>B. rochai</i> exhibited intraspecific variation in diploid number (2n = 16 and 2n = 18), representing the lowest diploid numbers ever reported fo2025-01-01T00:00:00Z20252026-06-05T17:22:25.239Z2026-05-19T03:12:03.126ZS-EPMC126356374128036510.3897/compcytogen.19.165160