Beyond Conus: Phylogenetic relationships of Conidae based on complete mitochondrial genomes

Abstract

Understanding how the extraordinary taxonomic and ecological diversity of cone snails (Caenogastropoda: Conidae) evolved requires a statistically robust phylogenetic framework, which thus far is not available. While recent molecular phylogenies have been able to distinguish several deep lineages within the family Conidae, including the genera Profundiconus, Californiconus, Conasprella, and Conus (and within this one, several subgenera), phylogenetic relationships among these genera remain elusive. Moreover, the possibility that additional deep lineages may exist within the family is open. Here, we reconstructed with probabilistic methods a molecular phylogeny of Conidae using the newly sequenced complete or nearly complete mitochondrial (mt) genomes of the following nine species that represent all main Conidae lineages and potentially new ones: Profundiconus teramachii, Californiconus californicus, Conasprella wakayamaensis, Lilliconus sagei, Pseudolilliconus traillii, Conus (Kalloconus) venulatus, Conus (Lautoconus) ventricosus, Conus (Lautoconus) hybridus, and Conus (Eugeniconus) nobilis. To test the monophyly of the family, we also sequenced the nearly complete mt genomes of the following three species representing closely related conoidean families: Benthomangelia sp. (Mangeliidae), Tomopleura sp. (Borsoniidae), and Glyphostoma sp. (Clathurellidae). All newly sequenced conoidean mt genomes shared a relatively constant gene order with rearrangements limited to tRNA genes. The reconstructed phylogeny recovered with high statistical support the monophyly of Conidae and phylogenetic relationships within the family. The genus Profundiconus was placed as sister to the remaining genera. Within these, a clade including Californiconus and Lilliconus+Pseudolilliconus was the sister group of Conasprella to the exclusion of Conus. The phylogeny included a new lineage whose relative phylogenetic position was unknown (Lilliconus) and uncovered thus far hidden diversity within the family (Pseudolilliconus). Moreover, reconstructed phylogenetic relationships allowed inferring that the peculiar diet of Californiconus based on worms, mollusks, crustaceans and fish is derived, and reinforce the hypothesis that the ancestor of Conidae was a worm hunter. A chronogram was reconstructed under an uncorrelated relaxed molecular clock, which dated the origin of the family shortly after the Cretaceous-Tertiary boundary (about 59million years ago) and the divergence among main lineages during the Paleocene and the Eocene (56-30million years ago).

Mitogenomic phylogeny of cone snails endemic to Senegal

“…Complete or near-complete (without the control region; see results) mt genomes were amplified through a combination of standard and long PCRs using the primers and following the protocols of Uribe et al (2016). Standard-PCR products were sequenced using Sanger technology.…”

“…The newly sequenced complete or nearly complete mt genomes were aligned with the mt genomes of A. borgesi (Cunha et al, 2009) from Boa Vista Island, Republic of Cabo Verde, and Lautoconus ventricosus (Uribe et al, 2016) from Faro, Portugal, which were used as outgroup taxa based on the phylogeny reported by Puillandre et al (2014). A sequence data set was constructed concatenating the nucleotide sequences of the 13 mt protein-coding and two rRNA genes.…”

“…Thus far, several molecular phylogenies have been reported either for the family Conidae (Puillandre et al, 2014;Uribe et al, 2016) or focused in particular geographic regions including the Indo-West Pacific (Duda and Palumbi, 1999;Duda and Kohn, 2005), Cape Verde archipelago (Cunha et al, 2005;Duda and Rolan, 2005;Cunha et al, 2008), Canary Islands (Cunha et al, 2014), Mozambique (Pereira et al, 2010) and…”

“…Conidae (Uribe et al, 2016). At present, the complete or near-complete mt genomes of 13 species belonging to the family Conidae are publicly available.…”

αO-Conotoxin GeXIVA disulfide bond isomers exhibit differential sensitivity for various nicotinic acetylcholine receptors but retain potency and selectivity for the human α9α10 subtype

“…Each concoction contains a unique complement of a thousand or more diverse components (Davis et al, 2009; Lavergne et al, 2015). Given the existence of more than 800 species of cone snails (Puillandre et al, 2015; Uribe et al, 2017) (REF), the library of toxins is immense. A number of cases of human fatalities from cone snail envenomation have occurred, and reports of “painless death” sparked interest in the analgesic properties of the venom (Livett et al, 2006).…”