In this project, we study hybridization, speciation and sex chromosome evolution in two Ischnura damselfly species occurring in Spain. One species has expanded recently and the newly established sympatric regions are the main focus because the two species are hybridizing here. We analyse population structure and introgression with SNPs for up to 20 individuals in several populations using resequencing and RAD-tag sequencing. We have been creating a draft genome which will be used during the down-stream analyses. Currently, we annotate the genome using Maker. We also use resequencing of males and females to study sex chromosome evolution. By using coverage analyses of newly sequenced individuals, we will determine which scaffolds of our present genome assembly belong to the X chromosome (females XX, males X0) and which are autosomal. When we have detected X-chromosome scaffolds, we will use already available RNAseq data to look for evidence of dosage compensation. In the near future, we will sequence additional individuals and also use 10XGenomics' Chromium technique to improve the assembly.