We present a genome assembly from an individual male Glyphotaelius pellucidus (Mottled Sedge, Arthropoda; Insecta; Trichoptera; Limnephilidae). The genome sequence is 1,037.1 megabases in span. Most of the assembly is scaffolded into 30 chromosomal pseudomolecules, including the assembled Z sex chromosome. The mitochondrial genome has also been assembled and is 16.0 kilobases in length. Gene annotation of this assembly on Ensembl identified 12,805 protein coding genes.