scholarly journals Few and far apart: integrative taxonomy of Australian species of Gladiobela and Pagodibela (Conoidea : Raphitomidae) reveals patterns of wide distributions and low abundance

2021 ◽  
Author(s):  
Anders Hallan ◽  
Francesco Criscione ◽  
Alexander Fedosov ◽  
Nicolas Puillandre
Keyword(s):  
Molecular Phylogeny ◽  
Deep Sea ◽  
Integrative Taxonomy ◽  
Taxonomic Study ◽  
Geographic Ranges ◽  
Suitable Material ◽  
Secondary Species ◽  
Australian Species ◽  
Full Species ◽  
The Pacific

The deep-sea malacofauna of temperate Australia remains comparatively poorly known. However, a recent influx of DNA-suitable material obtained from a series of deep-sea cruises has facilitated integrative taxonomic study on the Conoidea (Caenogastropoda:Neogastropoda). Building on a recent molecular phylogeny of the conoidean family Raphitomidae, this study focussed on the genera Gladiobela and Pagodibela (both Criscione, Hallan, Puillandre & Fedosov, 2020). We subjected a representative mtDNA cox1 dataset of deep-sea raphitomids to ABGD, which recognised 14 primary species hypotheses (PSHs), 9 of which were converted to secondary species hypotheses (SSHs). Following the additional examination of the shell and hypodermic radula features, as well as consideration of bathymetric and geographic data, seven of these SSHs were recognised as new to science and given full species rank. Subsequently, systematic descriptions are provided herein. Of these, five are attributed to Gladiobela (three of which are endemic to Australia and two more widely distributed) and two are placed in Pagodibela (one endemic to southern Australia and one widespread in the Pacific). The rarity of many ‘turrids’ reported in previous studies is confirmed herein, as particularly indicated by highly disjunct geographic records for two taxa. Additionally, several of the studied taxa exhibit wide Indo-Pacific distributions, suggesting that wide geographic ranges in deep-sea ‘turrids’ may be more common than previously assumed. Finally, impediments to deep-sea ‘turrid’ taxonomy in light of such comparative rarity and unexpectedly wide distributions are discussed.

scholarly journals Snails in depth: integrative taxonomy of Famelica, Glaciotomella and Rimosodaphnella (Conoidea: Raphitomidae) from the deep sea of temperate Australia

2021 ◽  
Author(s):  
Francesco Criscione ◽  
Anders Hallan ◽  
Nicolas Puillandre ◽  
Alexander Fedosov
Keyword(s):  
Deep Sea ◽  
Species Delimitation ◽  
New Genus ◽  
Morphological Characters ◽  
Integrative Taxonomy ◽  
New Genera ◽  
Undescribed Species ◽  
Suitable Material ◽  
Eastern Australia ◽  
The Family

The deep sea of temperate south-eastern Australia appears to be a ‘hotspot’ for diversity and endemism of conoidean neogastropods of the family Raphitomidae. Following a series of expeditions in the region, a considerable amount of relevant DNA-suitable material has become available. A molecular phylogeny based on this material has facilitated the identification of diagnostic morphological characters, allowing the circumscription of monophyletic genera and the introduction of several new genus-level taxa. Both named and new genera are presently being investigated through integrative taxonomy, with the discovery of a significant number of undescribed species. As part of this ongoing investigation, our study focuses on the genera Famelica Bouchet & Warén, 1980, Glaciotomella Criscione, Hallan, Fedosov & Puillandre, 2020 and Rimosodaphnella Cossmann, 1914. We subjected a comprehensive mitochondrial DNA dataset of representative deep-sea raphitomids to the species delimitation methods ABGD and ASAP that recognised 18 and 15 primary species hypotheses (PSHs) respectively. Following additional evaluation of shell and radular features, and examination of geographic and bathymetric ranges, nine of these PSHs were converted to secondary species hypotheses (SSHs). Four SSHs (two in Famelica and two in Rimosodaphnella) were recognised as new, and formal descriptions are provided herein.

scholarly journals An approach using ddRADseq and machine learning for understanding speciation in Antarctic Antarctophilinidae gastropods

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Juan Moles ◽  
Shahan Derkarabetian ◽  
Stefano Schiaparelli ◽  
Michael Schrödl ◽  
Jesús S. Troncoso ◽  
...  
Keyword(s):  
Machine Learning ◽  
Deep Sea ◽  
Weddell Sea ◽  
Nucleotide Polymorphisms ◽  
Sea Levels ◽  
Suitable Material ◽  
Genetic Lineages ◽  
Genome Wide ◽  
Gastropod Mollusks ◽  
Double Digestion

AbstractSampling impediments and paucity of suitable material for molecular analyses have precluded the study of speciation and radiation of deep-sea species in Antarctica. We analyzed barcodes together with genome-wide single nucleotide polymorphisms obtained from double digestion restriction site-associated DNA sequencing (ddRADseq) for species in the family Antarctophilinidae. We also reevaluated the fossil record associated with this taxon to provide further insights into the origin of the group. Novel approaches to identify distinctive genetic lineages, including unsupervised machine learning variational autoencoder plots, were used to establish species hypothesis frameworks. In this sense, three undescribed species and a complex of cryptic species were identified, suggesting allopatric speciation connected to geographic or bathymetric isolation. We further observed that the shallow waters around the Scotia Arc and on the continental shelf in the Weddell Sea present high endemism and diversity. In contrast, likely due to the glacial pressure during the Cenozoic, a deep-sea group with fewer species emerged expanding over great areas in the South-Atlantic Antarctic Ridge. Our study agrees on how diachronic paleoclimatic and current environmental factors shaped Antarctic communities both at the shallow and deep-sea levels, promoting Antarctica as the center of origin for numerous taxa such as gastropod mollusks.

Molecular phylogeny of the deep-sea penaeid shrimp genusParapenaeus(Crustacea: Decapoda: Dendrobranchiata)

2014 ◽  
Vol 44 (3) ◽  
pp. 312-323 ◽  
Author(s):  
Chien-Hui Yang ◽  
Zhongli Sha ◽  
Tin-Yam Chan ◽  
Ruiyu Liu
Keyword(s):  
Molecular Phylogeny ◽  
Deep Sea ◽  
Penaeid Shrimp

Analysis of Deep Sea Umbilical in Steep Wave Configuration

2016 ◽  
Author(s):  
Akash A. Nair ◽  
Gnanaraj A. Anbu ◽  
Panneer Selvam Rajamanickam ◽  
Gopakumar Kuttikrishnan ◽  
Ramadass Gidugu Ananda
Keyword(s):  
Deep Sea ◽  
Mining Machine ◽  
Optimum Number ◽  
Suitable Material ◽  
Static And Dynamic Analysis ◽  
Positive Displacement ◽  
Displacement Pump ◽  
Umbilical Cable ◽  
Steep Wave ◽  
Mother Ship

Deep sea mining is mineral retrieval process that takes place on the ocean floor wherein global industries are actively exploring and experimenting of different techniques in this relatively new concept of mining for extracting it economically from depths of 5000–5500 m below the ocean’s surface. National Institute of Ocean Technology (NIOT), India has been working on a mining concept for ∼6000 m water depth where a crawler based mining machine collects, crushes and pumps nodules to the mother ship using a positive displacement pump through a flexible riser (umbilical) system. The umbilical also serve as the weight supporting member for the miner and pump. In this paper, static and dynamic analysis of the umbilical system in steep wave configuration and the miner is carried out using ORCAFLEX for launching and touchdown conditions. Three different materials are considered and the best suitable material for umbilical is selected as the first step based on the tension. Then umbilical with Single Miner System is analyzed for the launching and touchdown conditions. Based on the analysis the optimum number and spacing of buoyancy tanks that will keep the stresses within the allowable limits in the umbilical cable are recommended.

Geochemistry of deep‐sea surface sediments from the pacific manganese nodule province near clarion island, Mexico

1993 ◽  
Vol 11 (3) ◽  
pp. 201-211 ◽  
Author(s):  
Leticia Rosales Hoz ◽  
Arturo Carranza Edwards
Keyword(s):  
Deep Sea ◽  
Surface Sediments ◽  
Manganese Nodule ◽  
Sea Surface ◽  
The Pacific

scholarly journals Thermophilic bacterial activity in a deep-sea sediment from the Pacific Ocean

1997 ◽  
Vol 13 ◽  
pp. 209-212 ◽  
Author(s):  
FC Dobbs ◽  
KA Selph
Keyword(s):  
Pacific Ocean ◽  
Deep Sea ◽  
Bacterial Activity ◽  
Deep Sea Sediment ◽  
The Pacific ◽  
The Pacific Ocean

scholarly journals Orientation of In Situ Stresses in the Pacific Plate: Deep Sea Drilling Project Hole 597C

1986 ◽  
Author(s):  
R.L. Newmark ◽  
R.N. Anderson ◽  
M.D. Zoback
Keyword(s):  
Deep Sea ◽  
Pacific Plate ◽  
In Situ Stresses ◽  
The Pacific ◽  
Drilling Project

scholarly journals Fish Teeth Sr Isotope Stratigraphy and Nd Isotope Variations: New Insights on REY Enrichments in Deep-Sea Sediments in the Pacific

2021 ◽  
Vol 9 (12) ◽  
pp. 1379
Author(s):  
Fenlian Wang ◽  
Gaowen He ◽  
Xiguang Deng ◽  
Yong Yang ◽  
Jiangbo Ren
Keyword(s):  
Deep Sea ◽  
Surface Sediments ◽  
Drake Passage ◽  
Marshall Islands ◽  
Early Oligocene ◽  
The Pacific ◽  
Deep Sea Sediments ◽  
Isotope Stratigraphy ◽  
Topographic Barriers ◽  
Fish Teeth

Rare earth elements and yttrium (REY) are widely recognized as strategic materials for advanced technological applications. Deep-sea sediments from the eastern South Pacific and central North Pacific were first reported as potential resources containing significant amounts of REY that are comparable to, or greater than, those of land-based deposits. Despite nearly a decade of research, quantitative abundances and spatial distributions of these deposits remain insufficient. Age controls are generally absent due to the lack of biostratigraphic constraints. Thus, the factors controlling the formation of REY-rich sediments are still controversial. In this study, the REY contents of surface sediments (<2 m depth) in 14 piston cores from the Middle and Western Pacific were investigated. The results show that deep-sea sediments with high REY contents (>1000 μg/g) were mainly concentrated around seamounts (e.g., the Marshall Islands). The REY contents of surface sediments generally decreased with distance from the seamounts. Biostratigraphic and fish teeth debris (apatite) Sr isotopic stratigraphy of one piston cores (P10) from the Middle Pacific indicate that deep-sea sediments with high REY contents were aged from early Oligocene to early Miocene. Since the opening of the Drake Passage during the early Oligocene, the northward-flowing Antarctic Bottom Water (AABW) would have led to an upwelling of nutrients around seamounts with topographic barriers, and at the same time, AABW would delay the rate of sediment burial to try for enough time for REY entering and enriching in the apatite (fish teeth debris). Understanding the spatial distribution of fertile regions for REY-rich sediments provides guidance for searching for other REY resources in the Pacific and in other oceans.

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