The complete mitochondrial genome of the southern purple-spotted gudgeon Mogurnda adspersa (Perciformes: Eleotridae) through pyrosequencing.

The complete mitochondrial genome of the Critically Endangered southern purple-spotted gudgeon, Mogurnda adspersa, was determined for the first time using 1/8 of a 454 pyrosequencing plate. The mitogenome was assembled using the bioinformatic software MIRA. The M. adspersa genome organization was very similar to most vertebrates, being 16,523 bp in length. It contained 13 protein-coding genes, 22 transfer RNA, 2 ribosomal RNA genes, and 1 non-coding control region. The current methodology was effective to assemble the whole mitogenome using 2008 mitochondrial reads representing 0.23% of total genomic reads produced and providing average mitogenome coverage of 17.4 reads per site. The whole mitogenome sequence provided here is deposited in NCBI with the accession number KJ130031 and may benefit systematics studies and conservation programs of M. adspersa.

The complete mitochondrial genome of two recently derived species of the fish genus Nannoperca (Perciformes, Percichthyidae).

Here we report the complete sequence of mitochondrial genomes for two sister taxa of freshwater teleosts, the recently derived Yarra pigmy perch Nannoperca obscura and the southern pigmy perch Nannoperca australis. These represent the first complete mitochondrial genomes for Percichthyidae (Perciformes), a family mostly distributed in Australia. The de novo genome assembly of 316,430 pyrosequencing reads from 454 libraries has produced the entire mitochondria for N. obscura and a nearly complete version for N. australis. The mtDNA genome from the latter was completed through the design of one primer set and standard Sanger sequencing for genome finishing, followed by the hybrid assembly of reads with MIRA software using N. obscura sequence as reference genome. The complete mitogenomes of N. obscura and N. australis are 16,496 and 16,494 bp in size, respectively. Both genomes contain 13 protein-coding genes, two ribosomal RNA genes, 22 transfer RNA genes and a control region. Several characteristics of mitochondria typically found in teleost fishes were detected, such as: (i) most genes found in the heavy strand, with the exception of ND6 and eight tRNA genes; (ii) avoidance of G as the third base of codons; (iii) presence of gene overlapping; (iv) percentage of bases usage. We found only eight indels and 197 nucleotide substitutions between these Nannoperca mitogenomes, consistent with a previous hypothesis of recent speciation. The data reported here provide a resource for comparative analysis of recent evolution of mitochondrial genomes.

Genetic characterization of native and introduced populations of the neotropical cichlid genus Cichla in Brazil.

A molecular phylogenetic analysis based on mitochondrial 16S ribosomal DNA and Control Region sequences from native and introduced populations was undertaken, in order to characterize the introduction of Cichla (peacock bass or tucunaré) species in Brazil. Mitochondrial DNA haplotypes found in introduced fish from Minas Gerais state (southeastern Brazil) clustered only with those from native species of the Tocantins River (Cichla piquiti and C. kelberi), thereby suggesting a single or, at most, few translocation acts in this area, even though with fish from the same source-population. Our study contributes to an understanding of the introduction of Cichla in regions of Brazil outside the Amazon basin, and adds phylogenetic data to the recently describe Cichla species, endemic from the Tocantins-Araguaia basin.