A tale of swinger insects: Signatures of past sexuality between divergent lineages of a parthenogenetic weevil revealed by ribosomal intraindividual variation

Abstract

Naupactus cervinus (Boheman) (Curculionidae, Naupactini) is a parthenogenetic weevil native to the Paranaense Forest which displays high levels of genetic variation. Two divergent clades were identified, one ranging in forest areas (Forest clade), and the other in open vegetation areas (Grassland clade). Both of them have individuals with high levels of heterozygosity in ribosomal sequences. Investigation of intraindividual variation in ITS1 sequences through cloning and posterior sequencing suggested that mating between both groups most likely occurred in the Paranaense Forest after a secondary contact, which led to fixed heterozygotes as a consequence of parthenogenesis. Otherwise, sexual segregation would have disrupted multilocus genotypes. Only a small number of heterozygous genotypes of all the possible combinations are found in nature. We propose the occurrence of a hybrid zone in the Paranaense Forest. The fact that it is one of the most important biodiversity hotspots of the world, together with its key role for investigating evolutionary processes, makes it worthy of conservation. This is the first genetic evidence of bisexuality in N. cervinus.

The Effect of Reproductive System on Invasiveness: Lessons from South American Weevils

“…Naupactus cervinus showed the highest level of genetic diversity. Twenty-four mitochondrial haplotypes (A-X) and 18 nuclear alleles (I-XvIII) were found, in addition to some traces of hybridization (N = 417) (Rodriguero et al 2010(Rodriguero et al , 2016(Rodriguero et al , 2018. Two highly divergent lineages were identified, 1 occurring in forest areas and another in open vegetation areas.…”

Aedes albopictus diversity and relationships in south-western Europe and Brazil by rDNA/mtDNA and phenotypic analyses: ITS-2, a useful marker for spread studies

“…Intra-individual variation in the sequence of the rDNA operon is unusual in animal genomes, although it has been reported in fishes and corals in relation to polyploidy, hybridization and a reduced rate of concerted evolution, and also in other insects [ 85 ]. In mosquitoes, intragenomic heterogeneity of rDNA spacers has been observed in Aedes and Culex [ 86 ] and in malaria Anopheles vectors [ 87 , 88 ].…”

Morphological and Molecular Perspectives on the Phylogeny, Evolution, and Classification of Weevils (Coleoptera: Curculionoidea): Proceedings from the 2016 International Weevil Meeting

“…She noted that parasitoids could play an important role in the horizontal transmission of the bacteria [95]. Members of her research group are developing the following projects: (1) a curing experiment using antibiotics to compare infected hosts with artificially cured hosts to test the effects of the bacterial infection on weevil females; (2) studies of ploidy using confocal microscopy in ovocites taken from ovarioles and in embryos; (3) transcriptomic studies on Naupactus cervinus Boheman and Naupactus leucoloma Boheman with the goal of identifying genes related to their colonization capacities (in collaboration with A. Sequeira); (4) hybridization as a possible mechanism for the origin of parthenogenetic reproduction in weevils through the study of intra-individual variation in ribosomal sequences [96]. Julien Haran reported on his collaborative works that used mitochondrial genome (mitogenome) sequences in reconstructing the phylogeny of weevils.…”