Mitogenomic insights into the deep-sea penaeid shrimp, Aristeus alcocki Ramadan, 1938.

The deep-sea shrimp, Aristeus alcocki Ramadan, 1938, is an economically valuable species belonging to the family Aristeidae under the superfamily Penaeoidea. In this study, we report the complete mitochondrial genome of A. alcocki, sequenced using Illumina high-throughput technology. The circular genome spans 15,938 bp and shows a strong A + T bias (64.15%), with nucleotide proportions of A: 31.59%, T: 32.56%, C: 14.00%, and G: 21.85%. Genome annotation identified the standard set of 37 mitochondrial genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), and 2 ribosomal RNAs (rRNAs). Detailed structural and sequence analyses were performed to characterize its mitogenomic framework. To elucidate evolutionary relationships, phylogenetic analyses were conducted using concatenated sequences of the 13 protein-coding genes (PCGs) from 24 species across five families-Aristeidae, Benthesicymidae, Solenoceridae, Sicyoniidae, and Penaeidae-of the superfamily Penaeoidea, with representatives from Sergestidae and Squillidae serving as outgroups. The resulting phylogeny refines the evolutionary placement of A. alcocki within Penaeoidea and provides additional support for the diversification patterns of Penaeoidea. Overall, this work expands the genomic resources for penaeid shrimps and offers a foundation for studies on deep-sea adaptation, systematics, and conservation of this economically valuable group.