The complete mitochondrial genome of Conus quercinus (Neogastropoda: Conidae).

The complete mitochondrial genome sequence of cone snail Conus quercinus a kind of worm-hunting sea snails, was performed by next-generation sequencing. The mitogenome is 16,439 bp in length, including 13 protein-coding genes, 22 tRNA genes, two ribosomal RNA genes (12S and 16S rRNA), and one control region. It has overall base composition of A (28.1%), T (38.2%), C (14.7%), and G (18.6%). It shows 75.9% identity with C. capitaneus, which also belongs to worm-hunting sea snail. The phylogenetic analysis was conducted with 22 closely related species to assess their phylogenetic relationship. The complete mitogenome of the C. quercinus provides important DNA molecular data for further phylogeography.

Mitochondrial genome sequences of landsnails Aegista diversifamilia and Dolicheulota formosensis (Gastropoda: Pulmonata: Stylommatophora).

The first mitochondrial genome sequences of Aegista and Dolicheulota belonging to Bradybaenidae are described in this report. Mitogenomic sequences were generated from Illumina paired-end sequencing. The complete mitogenome of Aegista diversifamilia was 14,039 bp in length and nearly complete mitogenome of Dolicheulota formosensis was 14,237 bp. Both mitogenomes consisted of 13 protein-coding genes (PCGs), 2 ribosomal RNA genes, and 22 transfer RNA genes. Most genes were overlapped with neighboring genes that the overlapping regions ranged from 2 to 64 bp in A. diversifamilia and from 1 to 45 bp in D. formosensis. Novel gene arrangement, tRNA-Tyr-ND3-tRNA-Trp, was identified in A. diversifamilia, whereas D. formosensis showed identical gene order to other Bradybaenidae mitogenomes. Maximum likelihood phylogenetic tree suggested Aegista as a sister clade to Euhadra and Dolicheulota. Bradybaenidae is monophyly sister clade to Camaenidae.

The complete mitochondrial genome of Conus tulipa (Neogastropoda: Conidae).

The complete mitogenome sequence of the cone snail Conus tulipa (Linnaeus, 1758) has been sequenced by next-generation sequencing method. The assembled mitogenome is 16,599 bp in length, including 13 protein-coding genes, 22 transfer RNA genes and 2 ribosomal RNA genes. The overall base composition of C. tulipa is 28.7% A, 15.2% C, 18.4% G and 37.7% T. It shows 81.1% identity to the cone snail C. consors, 78.5% to C. borgesi and 77.5% to C. textile. Using the 13 protein-coding genes and 2 ribosomal RNA genes of C. tulipa in this study, together with 18 other closely species, we constructed the species phylogenetic tree to verify the accuracy and utility of new determined mitogenome sequence. The complete mitogenome of the C. tulipa provides an essential and important DNA molecular data for further phylogeography and evolutionary analysis for cone snail phylogeny.

Mitochondrial DNA sequence of Conus textile (Neogastropoda: Conidae).

The cone snail Conus textile belongs to the family Conidae. It is a kind of molluscivorous species. The complete mitochondrial DNA sequence was constructed by next-generation sequencing in this study. The mitogenome of C. textile is 15,765 bp in length, including 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes and 1 control region. The base composition was 27.3% A, 37.9% T, 15.7% C and 19.1% G. The phylogenetic tree of C. textile with the other 6 Conus species and 15 Neogastropoda sea snails was built. It provides fundamental data for further research of phylogeny and biogeography with this genus.

The complete mitochondrial genome of Conus capitaneus (Neogastropoda: Conidae).

The complete mitochondrial genome sequence of cone snail Conus capitaneus, a kind of worm-hunting sea snails, was performed by next-generation sequencing. The mitogenome is 15,829 bp in length, including 13 protein-coding genes, 22 tRNA genes, 2 ribosomal RNA genes (12S and 16S rRNA) and 1 control region. It has an overall base composition of A (25.6%), T (36.6%), C (16.3%) and G (21.5%). It shows 79.8% identity with C. tribblei, which also belongs to worm-hunting sea snail. The phylogenetic analysis was conducted with 21 closely related species to assess their phylogenetic relationship. The complete mitogenome of the C. capitaneus provides important DNA molecular data for further phylogeography.

The complete mitochondrial genome of Conus striatus (Neogastropoda: Conidae).

Conus striatus is a kind of piscivorous cone snail. We have sequenced it by next generation sequencing method. We used de novo assembly and reference mapping methods to assemble mitogenome. The mitochondrial genome is 15,738 bp, containing 13 protein coding genes, 22 transfer RNAs and 2 ribosomal RNAs genes. The overall base composition of C. striatus is 25.9% for A, 16.3% for C, 20.8% for G and 38.6% for T. The phylogenetic analysis was conducted with 18 related species and confirmed the classification status. The complete mitogenome of the C. striatus provides an essential and important DNA molecular data for further phylogeography and evolutionary analysis for cone snail phylogeny.

Taxonomic revision of Aegistasubchinensis (Möllendorff, 1884) (Stylommatophora, Bradybaenidae) and a description of a new species of Aegista from eastern Taiwan based on multilocus phylogeny and comparative morphology.

Aegistasubchinensis (Möllendorff, 1884) is a widely distributed land snail species with morphological variation and endemic to Taiwan. Three genetic markers (partial sequence of the mitochondrial cytochrome c oxidase subunit I [COI], the 16S rDNA and the nuclear internal transcribed spacer 2 [ITS2]) were analysed to infer phylogenetic relationships and genetic divergence of closely related species of the genus Aegista, Aegistavermis (Reeve, 1852) and Aegistaoculus (Pfeiffer, 1850). A new species from Aegistasubchinensis has been recognized on the basis of phylogenetic and morphological evidences. The nominal new species, Aegistadiversifamilia sp. n. is distinguished from Aegistasubchinensis (Möllendorff, 1884) by its larger shell size, aperture and apex angle; wider umbilicus and flatter shell shape. The northernmost distribution of Aegistadiversifamilia sp. n. is limited by the Lanyang River, which is presumed to mark the geographic barrier between Aegistadiversifamilia sp. n. and Aegistasubchinensis.

Molluscan fauna of Gueishan Island, Taiwan.

This dataset records the occurrence and inventory of molluscan fauna on Gueishan Island, the only active volcanic island in Taiwan, based on the literature survey and field investigation conducted between 2011 and 2012. The literature review involved seven studies published from 1934 to 2003, which collectively reported 112 species from 61 genera and 37 families of Mollusca on Gueishan Island. Through our field investigation, we identified 34 species from 28 genera and 23 families. Fourteen of these species were new records on Gueishan Island: Liolophura japonica, Lottia luchuana, Nerita costata, Nerita rumphii, Diplommatina suganikeiensis, Littoraria undulata, Solenomphala taiwanensis, Assiminea sp., Siphonaria laciniosa, Laevapex nipponica, Carychium hachijoensis, Succinea erythrophana, Zaptyx crassilamellata, and Allopeas pyrgula. In Total, there are 126 species from 71 genera and 45 families of Mollusca on Gueishan Island. These data have been published through GBIF [http://taibif.org.tw/ipt/resource.do?r=gueishan_island] and integrated into the Taiwan Malacofauna Database (http://shell.sinica.edu.tw/).

Nucleotide sequence diversity at the methionine synthase locus in endangered Dunnia sinensis (Rubiaceae): an evaluation of the positive selection hypothesis.

Methionine synthase is a key enzyme for the synthesis of the aspartate-derived methionine, the immediate precursor of S-adenosyl-methionine, which has been illustrated to be associated with plant growth and pathogen interactions. In this study we tested the positive selection hypothesis of molecular evolution of the methionine synthase gene in Dunnia sinensis. In the entire sample of 87 sequences, 22 haplotypes of introns and 16 haplotypes of exons were identified. An excess of polymorphism over the neutral expectation for the class of unique nucleotide polymorphisms was observed in both exon and intron sequences. Ten replacement substitutions versus six synonymous substitutions among lineages, although nonsignificant, revealed that some advantageous mutants might have been favored. The distribution of d(N)/d(S) > 1 at nodes between closely related haplotypes in the gene network also indicated weak and variable positive selection. Nevertheless, low levels of genetic diversity in exons (theta; = 0.0052) and introns (theta; = 0.0070) of the methionine synthase gene of the outcrossing Dunnia were also attributed to the endangered status of the species. The atpB-rbcL intergenic spacer of cpDNA and the ribosomal internal transcribed spacer of mtDNA were used to discern the relative effectiveness of natural selection from intrinsic evolutionary forces. The low levels of nucleotide polymorphisms in both organelle spacers and the significant population differentiation reflected the effect of population-species history and demography. Two major lineages of the methionine synthase gene genealogy were recovered corresponding to two geographic regions, a result that was consistent with organelle phylogenies. Both past fragmentation and recent habitat disturbance causing complete bottlenecks may have resulted in population decline and geographic isolation and may have led to the depletion of genetic variation at loci in nuclear and organelle genomes.