When Did Decapods Invade Hydrothermal Vents? Clues from the Western Pacific and Indian Oceans

Abstract

Hydrothermal vents are typically located in midocean ridges and back-arc basins and are usually generated by the movement of tectonic plates. Life thrives in these environments despite the extreme conditions. In addition to chemoautotrophic bacteria, decapod crustaceans are dominant in many of the hydrothermal vents discovered to date. Contrary to the hypothesis that these species are remnants of relic fauna, increasing evidence supports the notion that hydrothermal vent decapods have diversified in more recent times with previous research attributing the origin of alvinocarid shrimps to the Miocene. This study investigated seven representative decapod species from four hydrothermal vents throughout the Western Pacific and Indian Oceans. A partitioned mix-model phylogenomic analysis of mitochondrial DNA produced a consistent phylogenetic topology of these vent-endemic species. Additionally, molecular dating analysis calibrated using multiple fossils suggested that both bythograeid crabs and alvinocarid shrimps originated in the late Mesozoic and early Cenozoic. Although of limited sampling, our estimates support the extinction/repopulation hypothesis, which postulates recent diversification times for most hydrothermal vent species due to their mass extinction by global deep-water anoxic/dysoxic events during the Late Cretaceous and Early Tertiary. The continental-derived property of the West Pacific province is compatible with the possibility that vent decapods diversified from ancestors from shallow-water regions such as cold seeps. Our results move us a step closer toward understanding the evolutionary origin of hydrothermal vent species and their distribution in the Western Pacific-Indian Ocean Region.

Complete mitochondrial genome of Rhynchocinetes durbanensis (Rhynchocinetidae: Rhynchocinetes)

“…Five of the 13 protein-coding genes (COX2, ATP6, ND4L, CYTB and ATP8) start with ATG, four of the 13 protein-coding genes (COX3, ND3, ND5 and ND2) start with ATT, ND6 and ND1 start with ATA, ND4 start with GTG, whereas the initiation codon of COX1 could not been determined. This phenomenon also been found in other shrimps, such as Rimicaris kairei (Yang et al 2012), Upogebia pusilla (Shen et al 2013) and Farfantepenaeus californiensis (Shen et al 2007). All protein-coding genes harboured the typical termination codon TAA.…”

Comparative population structure of two dominant species, Shinkaia crosnieri (Munidopsidae: Shinkaia) and Bathymodiolus platifrons (Mytilidae: Bathymodiolus), inhabiting both deep‐sea vent and cold seep inferred from mitochondrial multi‐genes

“…Vents have extremely high temperatures, high pressure levels, and high levels of toxins (Yang et al. 2013). Cold seeps, situated in subduction zones with ecosystems similar to vents, are areas where chemically modified fluids derived from hydrocarbon reservoirs, methane hydrates, pore waters in sediments, and sites of organic enrichment (such as whale skeletons) are released into the ocean (Van Dover et al.…”

Genetic population structure of four hydrothermal vent shrimp species (Alvinocarididae) in the Okinawa Trough, Northwest Pacific

“…Molecular evidence indicates that they were established during the late Cretaceous/Early Tertiary (Yang et al 2013). In the Northwest Pacific, alvinocaridids have been reported in the hydrothermal vent fields of the Okinawa Trough, the Izu-Bonin Arc, and the Mariana Arc, as well as in cold seep areas in Sagami Bay and the South China Sea (Komai & Segonzac 2005, Fujikura et al 2008, Li 2015.…”