Background The common long-arm octopus (Octopus minor) is found in mudflats of subtidal zones and faces numerous environmental challenges. The ability to adapt its morphology and behavioral repertoire to diverse environmental conditions makes the species a promising model for understanding genomic adaptation and evolution in cephalopods. Findings The final genome assembly of O. minor is 5.09 Gb, with a contig N50 size of 197 kb and longest size of 3.027 Mb, from a total of 419 Gb raw reads generated using the Pacific Biosciences RS II platform. We identified 30,010 genes; 44.43% of the genome is composed of repeat elements. The genome-wide phylogenetic tree indicated the divergence time between O. minor and Octopus bimaculoides was estimated to be 43 million years ago based on single-copy orthologous genes. In total, 178 gene families are expanded in O. minor in the 14 bilaterian species. Conclusions We found that the O. minor genome was larger than that of closely related O. bimaculoides, and this difference could be explained by enlarged introns and recently diversified transposable elements. The high-quality O. minor genome assembly provides a valuable resource for understanding octopus genome evolution and the molecular basis of adaptations to mudflats.

中文翻译：

---

常见的长臂章鱼小章鱼的基因组。

背景技术常见的长臂章鱼（章鱼小）在潮下带的滩涂中发现，面临许多环境挑战。能够使其形态和行为组成适应各种环境条件的能力使该物种成为了解头足类的基因组适应和进化的有前途的模型。研究结果小太平洋稻的最终基因组组装为5.09 Gb，重叠群N50大小为197 kb，最长大小为3.027 Mb，来自使用Pacific Biosciences RS II平台产生的总共419 Gb原始读数。我们鉴定了30,010个基因；基因组的44.43％由重复元件组成。全基因组的系统发育树表明，根据单拷贝直系同源基因，O。minor和Octopus bimaculoides之间的分歧时间估计为4300万年前。总共，在14个双边物种中，O。minor扩展了178个基因家族。结论我们发现小O.的基因组比紧密相关的O. bimaculoides的大，而这一差异可以用内含子的增加和最近多样化的转座因子来解释。高品质的O.minor基因组装配体为了解章鱼基因组进化和适应泥滩的分子基础提供了宝贵的资源。