Pholcus, males, sex chromosome behavior at spermatogonial mitosis and first meiotic division, Giemsa staining A P. dentatus, spermatogonial metaphase. Note the association of positively heteropycnotic sex chromosomes in the middle of the plate B P. silvai, early spermatogonial anaphase, three half plates. Sex chromosomes exhibit a slight positive heteropycnosis and are placed in the middle of the half plates. Sex chromosomes are marked by arrows C P. fuerteventurensis, early diffuse stage. Sex chromosomes form a positively heteropycnotic body on the periphery of the nucleus D P. silvai, late diffuse stage. The sex chromosome body on the periphery of the nucleus exhibits positive heteropycnosis E P. fuerteventurensis, diakinesis (11 bivalents and a X1X2Y trivalent). The Y chromosome stained more intensively than the X chromosomes. Note the scheme of sex chromosome pairing F P. alticeps, diplotene (11 bivalents and a X1X2Y trivalent). Edge of another diplotene separated by dotted line. Note the scheme of sex chromosome pairing. Abbreviations: SCB = sex chromosome body, SCT = sex chromosome trivalent, X1 = X1 chromosome, X2 = X2 chromosome, Y = Y chromosome. Scale bars: 10 μm.