Complete mitogenomes of four Trichiurus species: A taxonomic review of the T. lepturus species complex

Abstract

Four Trichiurus species, T. japonicus, T. lepturus, T. nanhaiensis, and T. brevis, from the coasts of the China Seas, have been identified and their entire mitochondrial genomes (mitogenomes) have been sequenced by next-generation sequencing technology. A comparative analysis of five mitogenomes was conducted, including the mitogenome of T. gangeticus. The mitogenomes contained 16.568–16.840 bp and encoded 36 typical mitochondrial genes (13 protein-coding, 2 ribosomal RNA-coding, and 21 transfer RNA-coding genes) and two typical noncoding control regions. Although tRNAPro is absent from Trichiurus mitogenomes, when compared with the 22 tRNAs reported in other vertebrates, the gene arrangements in the mitogenomes of the studied species are consistent with those in most teleost mitogenomes. The full-length sequences and protein-coding genes (PCGs) in the mitogenomes of the five species had obvious AT biases and negative GC skew values. Our study indicate that the specimens in the Indian Ocean are neither T. lepturus nor T. nanhaiensis but they are T. gangeticus; the Trichiurus species composition in the Indian Ocean is totally different from that in Pacific and Atlantic oceans; there are at least two Trichiurus species in Indian Ocean; and the worldwide systematics and diversity of the genus Trichiurus need to be reviewed.

Composition, Demographic History, and Population Structures of Trichiurus

“…Two species groups were recognized: the T. lepturus complex, which has an anal opening positioned vertically at the 38th to 41st dorsal fin rays, and the T. russelli complex, which has an anal opening positioned vertically at the 34th to 35th dorsal fin rays (Table 2) (Burhanuddin et al, 2002). Within the T. lepturus complex, T. japonicus has a longer tail, and T. lepturus has a whitish dorsal fin when fresh; in contrast, T. nanhaiensis has a yellowish-green dorsal fin (Hsu et al, 2009); the frontal bone of T. nanhaiensis is very smooth, the frontal bone of T. japonicus is slightly inverted, and the frontal bone of T. lepturus is obviously inverted and bulges in the upper part of the orbit and is accompanied by indentation (Figures S1, S2; Yi et al, 2022). A total of 1,551 bp of the COI gene was sequenced.…”

Complete Mitochondrial Genome of the Eggplant Fruit and Shoot Borer, Leucinodes orbonalis Guenée (Lepidoptera: Crambidae), and Comparison with Other Pyraloid Moths

“…The analysis of whole mitogenomes is attractive since they represent a compromise between single markers and whole genome analysis. The conserved properties of animal mitogenomes, the advantage of using multigene datasets, and the continued ease of acquisition would provide a promising strategy for species identification and population genetics using whole mitogenomes [21]. Whole mitogenomes were successfully used to determine the population structure of the Chinese seabass (Lateolabrax maculatus) in China [22] and Mansonia mosquitoes in Brazil [23].…”

Unveiling the reproductive and migrative behavior of Trichiurus lepturus in a tropical environment: Insights and implications

“…Trichiurus species play a significant role in commercial marine fisheries (FAO, 2004); however, their systematic classification remains unresolved due to the considerable resemblance among species within the genus, particularly in terms of physical appearance and silvery colouration (Yi et al, 2022). According to Eschmeyer's Catalog of Fishes (ECoF, Fricke et al, 2021), valid Trichiurus species are categorized into two complexes: the Trichiurus lepturus complex, often denoted as the large‐headed or long‐tailed species complex, and the Trichiurus russelli complex, known as the short‐tailed species complex (Burhanuddin et al, 2002).…”

“…The largehead hairtail, T. lepturus Linnaeus, 1758, has been registered as a cosmopolitan species exhibiting a broad global distribution and significant commercial value as a fishery resource on a global scale (Froese & Pauly, 2021; Martins et al, 2005). However, recent studies have reported that some published papers have misidentified this species in the Indian and Pacific oceans (Burhanuddin & Parin; Chakraborty & Iwatsuki, 2006; 2008; Yi et al, 2022). Its capture extends across a substantial portion of its habitat, encompassing both inshore and offshore waters.…”