Meiotic behavior of 18 species from eight families of terrestrial heteroptera

Abstract

Insects of the suborder Heteroptera are known for their odor, for being pests, or for being disease carriers. To gain better insight into the cytogenetic characteristics of heteropterans, 18 species of terrestrial Heteroptera belonging to eight families were studied. The presence of heteropycnotic corpuscles during prophase I, terminal or interstitial chiasmas, telomeric associations between chromosomes, ring disposals of autosomes during metaphase, and late migrations of the sex chromosomes during anaphase were analyzed. These features showed identical patterns to other species of Heteroptera previously described in the literature. Another studied characteristic was chromosome complements. The male chromosome complements observed were 2n = 12 chromosomes [10A + XY, Galgupha sidae (Amyot & Serville) (Corimelaenidae) and Pachycoris torridus (Scopoli) (Scutelleridae)]; 2n = 13 [10A + 2m + X0, Harmostes serratus (Fabricius), Harmostes apicatus (Stål), Jadera haematoloma (Herrich-Schaeffer), Jadera sanguinolenta (Fabricius), Jadera sp. (Rhopalidae)], and Neomegalotomus parvus (Westwood) (Alydidae); 2n = 13 [12A + X0, Stenocoris furcifera (Westwood) (Alydidae); 2n = 14 [12A + XY, Dictyla monotropidia (Stål) (Tingidae)]; 2n = 19 [18A + X0, Acanonicus hahni (Stål) (Coreidae)]; 2n = 21 [18A + 2m + X0, Acanthocephala sp. (Dallas) (Coreidae)]; 2n = 27 [24A + 2m + X0, Anisoscelis foliacea marginella (Dallas) (Coreidae)]; 2n = 18 [16A + XY, Oncopeltus fasciatus (Dallas) (Lygaeidae)]; 2n = 17 [14A + X1X2Y, Oxycarenus hyalinipennis (Costa) (Lygaeidae)]; 2n = 16 [12A + 2m + XY, Pachybrachius bilobatus (Say) (Lygaeidae)]; 2n = 26 [24A + XY, Atopozelus opsinus (Elkins) (Reduviidae)]; and 2n = 27 [24A + X1X2Y, Doldina carinulata (Stål) (Reduviidae)]. The diversity of the cytogenetic characteristics of Heteroptera was reflected in the 18 studied species. Thus, this study extends the knowledge of these characteristics, such as the variations related to chromosome complements, sex chromosome systems, and meiotic behavior.

Keywords: chromosome; cytogenetic; holocentric; meiosis.

Fig. 1.

Spermatogonial cells of N. parvus (a, i, k), O. fasciatus (b), At. opsimus (c), G. sidae (d), D. carinulata (e), H. serratus (f), J. sanguinolenta (g), Jadera sp. (h), An. foliacea marginella (j), A. hahni (l), and Ox. hyalinipennis (m) stained with lacto-acetic orcein. (a–e) Initial prophase showing an intensely stained, rounded heteropycnotic corpuscle (arrow in a), two closely associated corpuscles (arrow in b), less associated corpuscle (arrows in c), completely separate corpuscles (arrows in d), or three completely separate corpuscles (arrows in e); (f–j) the final stage of prophase, with persistent heteropycnotic corpuscles that are possibly the sex chromosomes (arrowhead in f and h). Other heteropycnotic chromosomal regions observed (arrows in g and h): (i–m) diplotene/diakinesis showing interstitial (arrows in i–l) or terminal (arrows in m) chiasmata. Bar: 10 µm.

Fig. 2.

Spermatogonial cells of D. carinulata (a–c), S. furcifera (d), G. sidae (e, f), Jadera sp. (g, i, l), J. haematoloma (h, o), An. foliacea marginella (j), A. hahni (k), Di. monotripidia (m), and Ox. hyalinipennis (n) stained with lacto-acetic orcein. (a–d) Chromosomes associating at their telomeres; they appear Z-shaped in (b); (e–f) telomeric association of a few chromosomes (arrows in e and inset); (g) association of telomeres between autosomes (arrow); (h) autosomes associated at nontelomeric regions (arrowheads). Notice the differentiated size of autosomes (f–i, arrows); (j) presence of m -chromosomes (arrowheads); (k) the circular arrangement of autosomes and a sex chromosome out of the ring (arrow shows the X chromosome); (l) autosomes arranged in a circle, with the X chromosome inside the ring (arrow) and the m -chromosomes in the center of the ring (arrowhead); (m, n) sex chromosomes in the center of the autosomal ring, X and Y (m) and X ₁ X ₂ Y (n); and (o) metaphase in a side view, with the heteropycnotic sex chromosome (arrow). Bar: 10 µm.

Fig. 3.

Spermatogonial cells of A. hahni (a, c), J. haematoloma (b, g, j, k, p), G. sidae (d, f, m), P. bilobatus (e), Ox. hyalinipennis (l), and O. fasciatus (h, i, n, o) stained with lacto-acetic orcein. (a, b) Anaphase I with lagging chromosome of the sex chromosome (a, arrow). Note that this chromosome remains heteropycnotic until the end of anaphase (b, arrow); (c) telophase II with a regular division, showing the heteropycnotic corpuscles (arrows); (d) material chromatin with late migration (arrows); (e, f) round spermatid with heteropycnotic material and a large vesicle (arrows); (g) round spermatid with chromatin around the nuclear envelope and inside the nucleus; (h, i) round spermatids with chromatin evenly distributed throughout the matrix and around the nuclear envelope; (j) elliptical spermatids presenting a larger vesicle (arrowhead) and several smaller vesicles (arrow); (k) spermatids being elongated with a single vesicle (arrow); (l) several small vesicles during differentiation (arrow); (m–p) spermatid in elongation, with coiled tail (n,o); and small head and long tail (p). Bar: 10 µm.

Fig. 4.

Metaphase cells of N. parvus (a), S. ( Oryzocoris ) furcifera (b), A. hahni (c), Acantocephala sp. (d), An. foliacea marginella (e), G. sidae (f), O. fasciatus (g), Ox. hyalinipennis (h), Pa. torridus (i), At. opsinus (j), D. carinulata (k), H. apicatus (l), H. serratus (m ), J. haematoloma (n), J. sanguinolenta (o), Jadera sp. (p), P. bilobatus (q), and Di. monotropidia (r) stained with lacto-acetic orcein. Asterisks indicate the X chromosomes, arrows show the Y, and the arrowhead indicates m -chromosomes. Bar: 10 µm.