S. (2012). The mitochondrial genomes of Cambaroides similis and Procambarus clarkii (Decapoda: Astacidea: Cambaridae): the phylogenetic implications for Reptantia. -Zoologica Scripta, 41, 281-292. We determined the complete mitochondrial (mt) genome sequences of two northern hemisphere freshwater crayfish species, Cambaroides similis and Procambarus clarkii (Decapoda: Astacidea: Cambaridae). These species have an identical gene order with typical metazoan mt genome compositions. However, their gene arrangement was very distinctive compared with the pan-crustacean ground pattern because of the presence of a long inverted block, which included 19 coding genes and a control region (CR). Because the CR was inverted, their nucleotide frequencies showed a reversed strand-specific bias compared with the other decapods. Based on a comparative analysis of mt genome arrangements between southern and northern hemisphere crayfish and their putative close marine relative (Homarus americanus, a true clawed lobster), we postulated that the ancestor of freshwater crayfish had a typical pan-crustacean mtDNA gene order, similar to its marine relatives. Based on this assumption, we traced the most parsimonious gene rearrangement scenario of the northern hemisphere crayfish. In a phylogenetic study on the infraordinal relationships in reptan decapods, the lineage Lineata [Thalassinidea (Brachyura, Anomura)] was well supported, while the infraorder positions of Achelata and Astacidea remained unidentified.Complete mitochondrial genomes of northern hemisphere crayfish d S. Kim et al.

We determined a full-length sequence of mitochondrial (mt) genome from Upogebia major. This is the first complete mt genome report for infraorder Thalassinidea in Decapoda, Crustacea. Our result showed that U. major generally followed a typical pancrustacean gene order but some tRNA genes showed a very unique gene arrangement such as duplication or translocation. Since none of the complete mt genome sequences in the infraorder Thalassinidea are available yet, this report will provide additional information in relation to mt genome diversity and evolution of the decapods.

We determined the complete mitochondrial (mt) genome sequence of the Japanese ghost shrimp Nihonotrypaea japonica (Ortmann 1891) (Crustacea, Decapoda, Axiidea). The N. japonica mt genome is first represented in infraorder Axiidea, which, together with infraorder Gebiidea, belonged to infraorder Thalassinidea until recently. The genome sequence of N. japonica is 15,274 bp in size, and the gene arrangement and transcriptional polarity are partially different from that of the Japanese mud shrimp, Upogebia major, which belongs to the infraorder Gebiidea. We present the mt genome of N. japonica, which could provide useful molecular information to construct a stable classification for infraorder Thalassinidea and to better understand the phylogenetic relationship of Thalassinidea with other decapod groups.

No abstract

The complete mitochondrial genome (mitogenome) of the red-banded lobster, Metanephrops thomsoni (Decapoda, Astacidea, Nephropidae), is 19,835 bp in length and contains 13 protein-coding genes (PCGs), 2 ribosomal RNAs, 24 transfer RNAs (including additional copies of trnW and trnL1), and 2 control regions (CR). The mitogenome of M. thomsoni has 10 long intergenic sequences (71-237 bp) with a high AT content (70.0%). The two CRs show 59.6% similarity and have an identical sequence region with a length of 295 bp. The mitogenome of M. thomsoni shows a novel gene arrangement compared with the pancrustacean ground pattern and is identical to that of M. sibogae, except for the two additional tRNAs (trnW and trnL1). Phylogenetic tree from maximum likelihood analysis using the concatenated sequences of 13 PCGs depicted M. thomsoni as one of the members of the superfamily Nephropoidea within Astacidea.