# Chromosome-level genome assembly of the stonefly Rhopalopsole triangulispina Mo and Li, 2025 (Plecoptera: Leuctridae)

## TL;DR

This paper presents a high-quality chromosome-level genome assembly for the stonefly Rhopalopsole triangulispina, aiding in understanding freshwater ecosystem health and insect evolution.

## Contribution

The study provides the first chromosome-level genome assembly for a species in the stonefly superfamily Nemouroidea.

## Key findings

- The genome assembly is 347.119 Mb with 96.91% anchored to 13 pseudochromosomes.
- The assembly has 98.4% completeness and encodes 12,857 protein-coding genes.

## Abstract

The superfamily Nemouroidea (Plecoptera) represents one of the most diverse and ecologically significant groups of stoneflies, with nymphs serving as crucial bioindicators of freshwater ecosystem health due to their sensitivity to water quality. However, the evolutionary and genomic studies of this group have been hindered by the lack of high-quality reference genomes. Here, we present a chromosome-level genome assembly for Rhopalopsole triangulispina Mo and Li, 2025 within Nemouroidea, generated by integrating PacBio HiFi long reads, Illumina short reads, and Hi-C chromatin interaction data. The final assembly spans 347.119 Mb with a scaffold N50 of 27.479 Mb, and 96.91% (336.39 Mb) of the genome is anchored to 13 pseudochromosomes. BUSCO assessment reveals a high completeness of 98.4% (insecta_odb10). The genome contains 48.50% repetitive elements (168.35 Mb) and encodes 12,857 protein-coding genes, which were comprehensively annotated using homology, transcriptomic, and ab initio evidence. This high-quality genome provides a foundational resource for resolving phylogenetic relationships within Nemouroidea, advancing studies on insect genome evolution, and enhancing freshwater biomonitoring efforts through genomic tools.