Fig. 132 in Diamonds in the rough: Ibotyporanga (Araneae, Pholcidae) spiders in semi-arid Neotropical environments

Fig. 132. Ibotyporanga Mello-Leitão, 1944, male chromosome plates of I. naideae Mello-Leitão (A, C–I) and Ibotyporanga sp. (B). A. Spermatogonial metaphase, including Y chromosome; note metacentric morphology and slight positive heteropycnosis of this element. B. Spermatogonial metaphase (2n = 30), including Y microchromosome. C. Premeiotic interphase; note a heteropycnotic body formed by sex chromosomes and rod-shaped element exhibiting weak heteropycnosis. D–E. Diffuse stage; note cluster comprising four heteropycnotic sex chromosomes (D) or sex chromosome body (E) and a heteropycnotic bivalent. F. Late prophase I consisting of 13 bivalents and sex chromosomes, which show considerable decondensation. One bivalent is positively heteropycnotic except for chiasma region. G. Sex chromosome tetravalent from metaphase I (separated by dashed line from bivalents); note scheme of sex chromosome pairing (blue – X chromosomes, orange – Y chromosome). H. Two sister metaphases II separated by dashed line. Left plate contains 16 chromosomes, right plate 14 chromosomes including small Y chromosome. Note predominance of biarmed chromosomes. I. Metaphase II containing 14 chromosomes; note small heteropycnotic Y chromosome. Arrows without letters point at sex chromosome body/cluster; arrowheads point at heteropycnotic bivalent/element. Abbreviations: X = X chromosome; Y = Y chromosome. Scale lines: A–F, H–I = 10 µm; G = 5 µm.