Resolving the status of Pyriporoides and Daisyella (Bryozoa: Cheilostomata), with the systematics of some additional taxa of Calloporoidea having an ooecial heterozooid

Based on the examination of type and newly discovered specimens, the scope of the calloporid genus Pyriporoides Hayward & Thorpe, 1989 is expanded to include Daisyella Gordon, 1989. All species of Pyriporoides have colonies of branching uniserial runners and acleithral ovicells that are borne on and/or develop concurrently with a distal heterozooid, not the distal autozooid. The ooecial heterozooid is usually kenozooidal but can be avicularian. Correlated characters include, inter alia: a raised granular rim that encloses a generally well-developed cryptocystal shelf, and a longitudinally elongate opesia that may be constricted and asymmetrical. Articulated perioral/pericryptocystal spines are present as well as occasional accessory spines borne on the lateral gymnocyst. Pyriporoides is mostly austral in distribution, ranging from the southern Indian Ocean and New Zealand’s subantarctic islands to West Antarctica, with an outlier in the northeast Atlantic. Three additional genera, one little known, two new to science, have species with small, mostly spot-like, colonies that share most of the zooidal characters of Pyriporoides and so are described and discussed in this context. These genera are Apiophragma Hayward & Ryland, 1993, Olisthella n. gen. and Bryobrownius n. gen. A cladistic analysis of the taxa described herein plus selected outgroup species of Calloporidae and Pyrisinellidae identified an apparent clade within or derived from Calloporidae, the significance of which is discussed.

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A cladistic phylogeny of the family Patellidae (Mollusca: Gastropoda)

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1998.0316 ◽

1998 ◽

Vol 353 (1375) ◽

pp. 1645-1671 ◽

Cited By ~ 51

Author(s):

S. A. Ridgway ◽

D. G. Reid ◽

J. D. Taylor ◽

G. M. Branch ◽

A. N. Hodgson

Keyword(s):

Indian Ocean ◽

Southern Africa ◽

Cladistic Analysis ◽

Sister Group ◽

Southern Indian Ocean ◽

Shell Shape ◽

Phylogenetic Hypothesis ◽

The Family ◽

Group Relationships ◽

Northeastern Atlantic

A phylogenetic hypothesis for the patellid limpets is reconstructed by cladistic analysis of morphological characters from 37 species, representing all but one of the living members of the family. Characters included in the analysis are derived from shell shape and microstructure, headfoot and pallial complex, radula and sperm. The species fall into four clades, providing the basis for a new phylogenetic classification into four monophyletic genera: Helcion (four species; southern Africa), Cymbula (eight species; southern Africa, eastern Atlantic, southern Indian Ocean), Scutellastra (17 species; southern and southwestern Africa, Australia, Indo–West Pacific, Eastern Pacific) and Patella (nine species; northeastern Atlantic and Mediterranean). The analysis suggests sister–group relationships between Helcion and Cymbula , and between Scutellastra and Patella . In combination with present–day patterns of geographical distribution, this phylogenetic hypothesis is used to discuss the historical biogeography of the Patellidae. Scutellastra may have originated in southern Africa and dispersed across the Pacific, or alternatively may be a primitively Tethyan group. Both Helcion and Cymbula appear to have originated in southern Africa, but three Cymbula species have dispersed respectively to northwest Africa, St Helena and the southern Indian Ocean. The patellids of the northeastern Atlantic form a single clade, Patella (including P. pellucida ), which may have arrived by northward dispersal of an ancestor from southern Africa, or possibly by vicariance of a widespread ancestral Tethyan distribution. The known fossil record of patellids is too fragmentary to permit choice between these alternatives.

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A Contest of Status and Legitimacy in the Indian Ocean

10.1093/oso/9780199479337.003.0002 ◽

2018 ◽

Author(s):

David Brewster

Keyword(s):

Indian Ocean ◽

International System ◽

Special Role ◽

Indian Ocean Region ◽

Major Powers ◽

Threat Perceptions ◽

Ocean Region ◽

The Status ◽

The Indian Ocean ◽

The Asymmetry

This chapter examines Indian and Chinese perspectives of each other as major powers and their respective roles in the Indian Ocean. It focuses on the following elements: (a) China’s strategic imperatives in the Indian Ocean Region, (b) India’s views on its special role in the Indian Ocean and the legitimacy of the presence of other powers, (c) China’s strategic vulnerabilities in the Indian Ocean and India’s wish to leverage those vulnerabilities, (d) the asymmetry in Indian and Chinese threat perceptions, and (d) Chinese perspectives of the status of India in the international system and India’s claims to a special role in the Indian Ocean. The chapter concludes that even if China were to take a more transparent approach to its activities, significant differences in perceptions of threat and over status and legitimacy will produce a highly competitive dynamic between them in the maritime domain.

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Seasonality and Dynamics of Atmospheric Teleconnection from the Tropical Indian Ocean and the Western Pacific to West Antarctica

Atmosphere ◽

10.3390/atmos12070849 ◽

2021 ◽

Vol 12 (7) ◽

pp. 849

Author(s):

Hyun-Ju Lee ◽

Emilia-Kyung Jin

Keyword(s):

Indian Ocean ◽

Rossby Wave ◽

Tropical Indian Ocean ◽

Western Pacific ◽

Tropical Region ◽

Formation Mechanisms ◽

West Antarctica ◽

Background Flow ◽

The Impact ◽

The Western Pacific

The global impact of the tropical Indian Ocean and the Western Pacific (IOWP) is expected to increase in the future because this area has been continuously warming due to global warming; however, the impact of the IOWP forcing on West Antarctica has not been clearly revealed. Recently, ice loss in West Antarctica has been accelerated due to the basal melting of ice shelves. This study examines the characteristics and formation mechanisms of the teleconnection between the IOWP and West Antarctica for each season using the Rossby wave theory. To explicitly understand the role of the background flow in the teleconnection process, we conduct linear baroclinic model (LBM) simulations in which the background flow is initialized differently depending on the season. During JJA/SON, the barotropic Rossby wave generated by the IOWP forcing propagates into the Southern Hemisphere through the climatological northerly wind and arrives in West Antarctica; meanwhile, during DJF/MAM, the wave can hardly penetrate the tropical region. This indicates that during the Austral winter and spring, the IOWP forcing and IOWP-region variabilities such as the Indian Ocean Dipole (IOD) and Indian Ocean Basin (IOB) modes should paid more attention to in order to investigate the ice change in West Antarctica.

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AN ABERRANTLY PIGMENTED SOUTHERN ELEPHANT SEAL (MIROUNGA LEONINA) AT ILES KERGUELEN, SOUTHERN INDIAN OCEAN

Marine Mammal Science ◽

10.1111/j.1748-7692.2000.tb00964.x ◽

2000 ◽

Vol 16 (3) ◽

pp. 681-684 ◽

Cited By ~ 8

Author(s):

Joel Bried ◽

Daniel Haubreux

Keyword(s):

Indian Ocean ◽

Elephant Seal ◽

Southern Indian Ocean ◽

Southern Elephant Seal ◽

Mirounga Leonina

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Life history characteristics ofAlticus monochrus, a supratidal blenny of the southern Indian Ocean

African Zoology ◽

10.1080/15627020.2006.11407330 ◽

2006 ◽

Vol 41 (1) ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

M. Bhikajee ◽

J. M. Green ◽

R. Dunbrack

Keyword(s):

Life History ◽

Indian Ocean ◽

Southern Indian Ocean ◽

Life History Characteristics

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Getting Tsunami Recovery and Early Warning Right

Open House International ◽

10.1108/ohi-01-2006-b0007 ◽

2006 ◽

Vol 31 (1) ◽

pp. 54-61

Author(s):

Ben Wisner ◽

Peter Walker

Keyword(s):

Indian Ocean ◽

Early Warning ◽

Warning System ◽

Status Quo ◽

Indian Ocean Tsunami ◽

Tropical Storms ◽

Warning Systems ◽

Tsunami Warning System ◽

Policy Makers ◽

The Status

The massive human and economic impact of the Asian tsunami in later 2004 is mirrored in the aftershocks felt among humanitarian organisations, development agencies, and policy makers. This paper raises a number of these troubling, fundamental issues. Firstly, the call for an Indian Ocean tsunami warning system raises fundamental issues about what warning systems can, and cannot, do. Secondly, one is also forced to consider why in the first place so many people live on exposed coasts today, vulnerable not only to tsunamis but tropical storms and rainy season flooding among other hazards. Thirdly, one is challenged to question the very meaning of “recovery”. Such massive damage has been done and so many people and their livelihoods have been dislocated, is it actually possible to imagine a return to the status quo ante? Fourthly, reconstruction of the magnitude now underway in the affected areas raises many difficult questions about accountability, transparency, and the unevenness with which the international community responds to crises. The paper finishes with some recommendations.

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Continuous flow analysis of the Mount Brown South ice core

10.5194/egusphere-egu21-15782 ◽

2021 ◽

Author(s):

Margaret Harlan ◽

Helle Astrid Kjær ◽

Tessa Vance ◽

Paul Vallelonga ◽

Vasileios Gkinis ◽

...

Keyword(s):

Indian Ocean ◽

Size Distribution ◽

Continuous Flow ◽

Ice Core ◽

Flow Analysis ◽

East Antarctica ◽

Southern Indian Ocean ◽

Indian Ocean Region ◽

Continuous Flow Analysis ◽

Ocean Region

The Mount Brown South (MBS) ice core is an approximately 300-meter-long ice core, drilled in 2016-2017 to the south of Mount Brown, Wilhelm II Land, East Antarctica. This location in East Antarctica was chosen as it produces an ice core with well-preserved sub-annual records of both chemistry and isotope concentrations, spanning back over 1000 years. MBS is particularly well suited to represent climate variations of the Indian Ocean sector of Antarctica, and to provide information about regional volcanism in the Southern Indian Ocean region.A section of ice spanning the length of the MBS core was melted as part of the autumn 2019 continuous flow analysis (CFA) campaign at the Physics of Ice, Climate, and Earth (PICE) group at the University of Copenhagen. During this campaign, measurements were conducted for chemistry and impurities contained in the ice, in addition to water isotopes. The data measured in Copenhagen include measurements of H2O2, pH, electrolytic conductivity, and NH4+, Ca2+, and Na+&#160;ions, in addition to insoluble particulate concentrations and size distribution measured using an Abakus laser particle counter.Here, we present an overview of the CFA chemistry and impurity data, as well as preliminary investigations into the size distribution of insoluble particles and the presence of volcanic material within the ice. These initial chemistry and particulate size distribution data sets are useful in order to identify sections of the MBS core to subject to further analysis to increase our understanding of volcanic activity in the Southern Indian Ocean region.

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