scholarly journals A basilosaurid archaeocete (Cetacea, Pelagiceti) from the Late Eocene of Oregon, USA

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9809
Author(s):  
Mark D. Uhen ◽  
David Taylor
Keyword(s):  
North Pacific ◽  
Gulf Coast ◽  
Late Eocene ◽  
Thoracic Vertebrae ◽  
The North ◽  
The World ◽  
Gulf Coast Region ◽  
The North Pacific ◽  
Coast Region ◽  
North Pacific Basin

Background Basilosaurid archaeocetes are known from the Late Eocene of virtually all coastlines bearing coeval marine rocks except the North Pacific Basin, until now. Here we report on three consecutive posterior thoracic vertebrae of a large, basilosaurid archaeocete from a Late Eocene horizon in the Keasey Formation in Oregon. Methods These vertebrae were morphologically and morphometrically compared to other vertebrae of similar age from around the world. Results The specimens were determined to be different from all currently named species of fossil cetacean, but most similar to those found in the Gulf Coast region of North America. These vertebrae represent the first confirmed specimen of a Late Eocene basilosaurid from the North Pacific. These and other basilosaurids known only from vertebrae are reviewed here in the context of Late Eocene paleoceanography and cetacean evolution.

Revision of the genus Anophryocephalus Baylis, 1922 from pinnipeds in the Holarctic, with descriptions of Anophryocephalus nunivakensis sp.nov. and A. eumetopii sp.nov. (Tetrabothriidae) and evaluation of records from the Phocidae

1991 ◽  
Vol 69 (6) ◽  
pp. 1653-1668 ◽  
Author(s):  
Eric P. Hoberg ◽  
Ann M. Adams ◽  
Robert L. Rausch
Keyword(s):  
Bering Sea ◽  
North Pacific ◽  
Pacific Basin ◽  
Genital Papilla ◽  
High Latitudes ◽  
Eumetopias Jubatus ◽  
The North ◽  
Phoca Largha ◽  
The North Pacific ◽  
North Pacific Basin

Anophryocephalus Baylis, 1922 is emended to include tetrabothriid cestodes with intricate scolices (paired auricular appendages and bothridial operculae), complex genital atria (muscular chamber ventral to the vagina; muscular pad adjacent to the aperture of the male canal), and atrophy of the dorsal osmoregulatory system. Anophryocephalus anophrys (type), A. skrjabini, and A. ochotensis are redescribed. Anophryocephalus nunivakensis sp.nov., from Phoca largha, has bothridial operculae with broad anterior apertures, an ovoid cirrus sac (57–95 μm in diameter), a ventrolaterally directed male canal (26–44 μm long in mature segments), and 26–56 testes. Anophryocephalus eumetopii sp.nov., from Eumetopias jubatus, has bothridial operculae with narrow, slitlike, diagonally directed apertures, a spheroidal cirrus sac (51–72 μm in diameter), a prominent genital papilla and ventrolaterally directed male canal (36–51 μm long in mature segments), and 32–66 testes. Postlarval ontogeny of the scolex among some species of Anophryocephalus appears similar to that known for Tetrabothrius spp., suggesting uniformity in morphogenesis of the holdfast among the Tetrabothriidae. Anophryocephalus spp. are typical parasites of pinnipeds in the Holarctic, and contrary to previous reports, A. skrjabini and A. ochotensis are exclusively parasites of Phoca spp. and Eumetopias jubatus, respectively, at high latitudes in the North Pacific basin and Bering Sea.

scholarly journals Natal origin of Namibian grey whale implies new distance record for in-water migration

2021 ◽  
Vol 17 (6) ◽  
pp. 20210136
Author(s):  
A. Rus Hoelzel ◽  
Fatih Sarigol ◽  
Tess Gridley ◽  
Simon H. Elwen
Keyword(s):  
North Pacific ◽  
Western North Pacific ◽  
Water Migration ◽  
Natal Origin ◽  
The North ◽  
Pacific Population ◽  
Conservation Implications ◽  
Grey Whale ◽  
The World ◽  
The North Pacific

We use genomics to identify the natal origin of a grey whale found in the South Atlantic, at least 20 000 km from the species core range (halfway around the world). The data indicate an origin in the North Pacific, possibly from the endangered western North Pacific population, thought to include only approximately 200 individuals. This contributes to our understanding of Atlantic sightings of this species known primarily from the North Pacific, and could have conservation implications if grey whales have the potential for essentially global dispersion. More broadly, documenting and understanding rare extreme migration events have potential implications for the understanding of how a species may be able to respond to global change.

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