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bioRxiv · 10.1101/2025.07.14.664635

Nuclear and mitochondrial genome assemblies of Indrella ampulla, a terrestrial gastropod endemic to the Western Ghats

Abstract

Indrella ampulla is a polymorphic, brightly coloured, forest-dwelling land snail endemic to the Western Ghats of India. Studying and understanding evolutionary processes occurring within this species has remained a challenge largely due to a paucity of genomic resources. We present high-quality annotated nuclear and mitochondrial genome assemblies of I. ampulla. The nuclear genome is assembled through a hybrid approach using Illumina short reads and Oxford Nanopore long reads, with an N50 value of 632 kb and 90.3% BUSCO genome completeness. The mitogenome is 13,887 bp long. The demographic history reconstruction based on the genomic data exhibits signatures of population decline during the last 100,000 years. This genome will aid in deciphering the colour polymorphism in I. ampulla and augmenting the general understanding of the evolution of gastropods. SignificanceIndrella ampulla is a terrestrial gastropod endemic to the Western Ghats biodiversity hotspot, and exhibits color polymorphism. The genome of I. ampulla provides a valuable resource for understanding molluscan biology, coloration genetics, adaptation, and other evolutionary processes. Our historical demographic analysis offers insights into past population dynamics of this species endemic to the Western Ghats of India, contributing to broader research on biodiversity patterns in tropical ecosystems. The bioinformatics pipeline used in this study provides a reliable framework for assembling high-quality genomes with long-read coverage as low as 10X, making it especially useful for gastropods and other species where obtaining high coverage data is a challenge. Overall, this genome will complement future studies in phylogenomics, comparative genomics, and conservation of molluscs.

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BibTeXRIS

Krishnan, G., Sil, M., Aravind, N. A., Umapathy, G., Datta-Roy, A.. 2025-07-18. Nuclear and mitochondrial genome assemblies of Indrella ampulla, a terrestrial gastropod endemic to the Western Ghats. https://doi.org/10.1101/2025.07.14.664635

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