Cytogenetics of Seven Species of Dragonflies A Novel Sex Chromosome Determining System in Micrathyria Ungulate

Abstract

More than 80% of the taxonomically described species of Anisoptera (Odonata) belong to the families Libellulidae and Aeshnidae. Here the chromosome complement and male meiotic behaviour of seven species of dragonflies of these families are analyzed. Anax amazili and Coryphaeschna perrensi are 2n = 27, n = 13 + X, which is characteristic of Aeshnidae. Within Libellulidae, Planiplax erythropyga, Micrathyria spuria and M. hesperis have 2n = 25, n = 12 + X, which corresponds to the modal chromosome number of the family. Oligoclada laelitia and M. ungulata, on the other hand, have a reduced chromosome complement (n = 11 + X and n = 10 + X1X2Y, respectively). In Micrathyria ungulata an X1X2Y sex chromosome system is described, and its origin is discussed. This represents a new sex chromosome determining system in the order Odonata.

Fluorescent banding and meiotic behaviour in Erythrodiplax nigricans (Libellulidae) and Coryphaeschna perrensi (Aeschnidae) (Anisoptera, Odonata)

“…The population of C. perrensi from "Eldorado" (Misiones Province) analysed in this work and that from Iguazú National Park (Misiones Province) studied previously show a similar meiotic development (MOLA et al 1999). In the former population, however, the largest bivalent has two chiasmata in a high proportion of cells (19%), which is a very rare feature among dragonflies.…”

“…The species that have been cytogenetically analysed are C. adnexa, C. perrensi and C. viriditas (CUMMING 1964;KIAUTA 1979;MOLA et al 1999). The former two species exhibit characteristics typical of the family (n= 13+XO male), while C. viriditas has a reduced chromosome complement (n=12+XO male).…”

“…The most frequent sex chromosome mechanism is XX/X0, being the male the heterogametic sex; the derived neo-XY system occurs in approximately 5.5% of the species, and the X 1 X 1 X 2 X 2 /X 1 X 2 Y multiple system is only present in Micrathyria ungulata (MOLA et al 1999). The presence of a small pair of autosomes, the m-chromosomes, is found in nearly 80% of the species; it shows a regular meiotic behaviour, and is solely characterised by its size, and in some cases by its negative heteropycnosis.…”

Chromosomal analysis of eight species of dragonflies (Anisoptera) and damselflies (Zygoptera) using conventional cytogenetics and fluorescence in situ hybridization: Insights into the karyotype evolution of the ancient insect order Odonata

“…Chromosomal rearrangements, among which fission and fusions were presumably predominating, led to the appearance of divergent karyotypes in the evolution of Odonata. We note in this connection, that in many dragonfly and damselfly families, other karyotypes, when occuring, are clearly derivative as indicated by a diverged number of autosomes or secondary sex chromosome systems of an XY‐type or both (e.g., Agopian & Mola, 1984, 1988; Cumming, 1964; Kiauta, 1969a, 1969b; Mola et al., 1999; Perepelov & Bugrov, 2002).…”

Cytogenetic Characterization of Eight Odonata Species Originating from the Curonian Spit (the Baltic Sea, Russia) Using C-Banding and FISH with 18S rDNA and Telomeric (TTAGG)_n Probes

“…In addition, their chromosomes appear fairly uniform in size within a karyotype. Deviations from these patterns are rare [e.g., Agopian and Mola, 1988;Mola, 1995;Mola et al, 1999;Perepelov and Bugrov, 2002;Grozeva and Marinov, 2007;Walia et al, 2011;Walia and Chahal, 2014]. Despite maintaining the same karyotype in the majority of species, the diploid chromosome numbers in male Odonata vary over a rather wide range, from 5 to 41 [Agopian and Mola, 1988].…”