Salishicetus meadi
            , a new aetiocetid from the late Oligocene of Washington State and implications for feeding transitions in early mysticete evolution

Living baleen whales, or Mysticeti, lack teeth and instead feed using keratinous baleen plates to sieve prey-laden water. This feeding strategy is profoundly different from that of their toothed ancestors, which processed prey using the differentiated dentition characteristic of mammals. The fossil record of mysticetes reveals stem members that include extinct taxa with dentition, illuminating the morphological states that preceded the loss of teeth and the subsequent origin of baleen. The relationships among stem mysticetes, including putative clades such as Mammalodontidae and Aetiocetidae, remain debatable. Aetiocetids are among the more species-rich clade of stem mysticetes, and known only from fossil localities along the North Pacific coastline. Here, we report a new aetiocetid, Salishicetus meadi gen. et sp. nov, from the late Oligocene of Washington State, USA. Salishicetus preserves a near-complete lower dentition with extensive occlusal wear, indicating that it processed prey using shearing cheek teeth in the same way as its stem cetacean ancestors. Using a matrix with all known species of aetiocetids, we recover a monophyletic Aetiocetidae, crownward of a basal clade of Mammalodontidae. The description of Salishicetus resolves phylogenetic relationships among aetiocetids, which provides a basis for reconstructing ancestral feeding morphology along the stem leading to crown Mysticeti.

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New Nanaimo Group ammonites (Cretaceous, Santonian–Campanian) from British Columbia and Washington State

Journal of Paleontology ◽

10.1017/s0022336000019247 ◽

1989 ◽

Vol 63 (2) ◽

pp. 218-227 ◽

Cited By ~ 12

Author(s):

James W. Haggart ◽

Peter D. Ward

Keyword(s):

United States ◽

British Columbia ◽

North Pacific ◽

Washington State ◽

Western Canada ◽

Pacific Region ◽

The North ◽

North Pacific Region ◽

The North Pacific

The ammonite species Puzosia (Mesopuzosia) densicostata Matsumoto, Kitchinites (Neopuzosia) japonicus Spath, Anapachydiscus cf. A. nelchinensis Jones, Menuites cf. M. menu (Forbes), Submortoniceras chicoense (Trask), and Baculites cf. B. boulei Collignon are described from Santonian–Campanian strata of western Canada and northwestern United States. Stratigraphic occurrences and ranges of the species are summarized and those taxa important for correlation with other areas in the north Pacific region are noted.

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New late Eocene and Oligocene plotopterid fossils from Washington State (USA), with a revision of “Tonsala” buchanani (Aves, Plotopteridae)

Journal of Paleontology ◽

10.1017/jpa.2021.81 ◽

2021 ◽

pp. 1-13

Author(s):

Gerald Mayr ◽

James L. Goedert

Keyword(s):

North Pacific ◽

Late Eocene ◽

Current Data ◽

Washington State ◽

Kelp Forests ◽

Sexually Dimorphic ◽

Western North America ◽

The North ◽

Western Washington ◽

The North Pacific

Abstract We report new specimens of the Plotopteridae from Washington State (USA), an area where these flightless seabirds underwent significant diversification during the late Eocene and Oligocene. To date, five plotopterid species from western Washington have been formally named. Specimens previously assigned to Tonsala buchanani Dyke, Wang, and Habib, 2011 belong to at least two, but probably even three, different species. One of these, the large-sized “Whiskey Creek specimen” from late Eocene deposits mapped as the Makah Formation, is the oldest known plotopterid and is here tentatively assigned to ?Klallamornis clarki Mayr and Goedert, 2016. Another specimen originally referred to T. buchanani is also likely to belong to a different species and is among the most substantial records for North American plotopterids. We formally transfer T. buchanani to the taxon Klallamornis and show that the only unambiguously identified specimen of the species—the holotype—is currently poorly diagnosed from Klallamornis abyssa Mayr and Goedert, 2016, which is from coeval strata of the Pysht Formation. Although the holotype of K. abyssa is larger than that of K. buchanani, there remains a possibility that plotopterids were sexually dimorphic in size. We describe the first ungual phalanx of a plotopterid, which is referred to K. buchanani, and report previously unknown elements of the large ?K. clarki and the first records of this species from the Lincoln Creek Formation. Current data indicate that plotopterids originated in the middle or late Eocene on islands off western North America, and we hypothesize that the radiation of these birds in the North Pacific Basin may have been related to the evolution of kelp forests.

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A new specimen ofAgorophius pygmaeus(Agorophiidae, Odontoceti, Cetacea) from the early Oligocene Ashley Formation of South Carolina, USA

Journal of Paleontology ◽

10.1017/jpa.2016.4 ◽

2016 ◽

Vol 90 (1) ◽

pp. 154-169 ◽

Cited By ~ 11

Author(s):

Stephen J. Godfrey ◽

Mark D. Uhen ◽

Jason E. Osborne ◽

Lucy E. Edwards

Keyword(s):

South Carolina ◽

North Pacific ◽

Washington State ◽

The North ◽

Early Oligocene ◽

The Family ◽

North Pacific Region ◽

First Time ◽

Ashley River ◽

The North Pacific

AbstractThe holotype partial skull ofAgorophius pygmaeus(the monotypic form for both the genusAgorophiusand the Family Agorophiidae) has been missing for approximately 140 years. Since the discovery ofAgorophius pygmaeus, many additional taxa and specimens have been placed in the Family Agorophiidae, only to be reclassified and removed later. This has created confusion as to what is and what is not an agorophiid and a lack of clarity as to what characteristics delimit the Agorophiidae. A newly discovered skull of an agorophiid recently collected from an underwater cliff face of the Ashley River, South Carolina, USA, is assigned toAgorophius pygmaeus. It derives from the base of the Ashley Formation (early Oligocene). The new specimen consists of most of the skull and periotics, which are well preserved and described for the first time in an agorophiid. The new specimen provides an opportunity to diagnose the Agorophiidae and place the genus and species within the phylogenetic context of the early odontocete radiation in the Oligocene, along with other taxa such as the Ashleycetidae, Mirocetidae, Patriocetidae, Simocetidae, Waipatiidae, and Xenorophidae. Based on this new understanding, Agorophiidae are known with certainty only from the early Oligocene of South Carolina, with other undescribed, potential agorophiid specimens from the Oligocene of the North Pacific region (Japan, Mexico, and Washington State).

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The occurrence of shearwaters (Puffinus spp.) off the west coast of Canada

Canadian Journal of Zoology ◽

10.1139/z83-271 ◽

1983 ◽

Vol 61 (9) ◽

pp. 2064-2077 ◽

Cited By ~ 4

Author(s):

Juan R. Guzman ◽

M. T. Myres

Keyword(s):

British Columbia ◽

Continental Shelf ◽

West Coast ◽

North Pacific ◽

Gulf Of Alaska ◽

Washington State ◽

The West ◽

The North ◽

The Relationship ◽

The North Pacific

Shearwaters, Puffinus spp., were studied off the west coast of Canada from 1975 to 1978. Sooty shearwaters, P. griseus, were the most abundant shearwaters off British Columbia in both May and September–October. Pink-footed shearwaters, P. creatopus, also occurred in both spring and fall. Flesh-footed shearwaters, P. carneipes, were found only in May. Buller's shearwaters, P. bulleri, were encountered in June and July during cruises across the Gulf of Alaska and in September and October off British Columbia. The recent increase of Buller's shearwater in the North Pacific is documented. A review of records of the short-tailed shearwater, P. tenuirostris, shows that it is usually rare and irregular off the coast of British Columbia. One black-vented shearwater, P. opisthomelas, was seen in the Gulf of Alaska. Sooty shearwaters occur off British Columbia in far lower numbers than off northern California, Oregon or Washington State. The manner in which sooty shearwaters migrate is described. The relationship between shearwater distributions and depths of water over the continental shelf are examined.

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Oldest record of monk seals from the North Pacific and biogeographic implications

Biology Letters ◽

10.1098/rsbl.2019.0108 ◽

2019 ◽

Vol 15 (5) ◽

pp. 20190108 ◽

Cited By ~ 3

Author(s):

Jorge Velez-Juarbe ◽

Ana M. Valenzuela-Toro

Keyword(s):

North Pacific ◽

Fossil Record ◽

Marine Mammals ◽

Pacific Region ◽

The North ◽

Biogeographic History ◽

History Of ◽

North Pacific Region ◽

Monk Seals ◽

The North Pacific

True seals (crown Phocidae) originated during the late Oligocene–early Miocene (approx. 27–20 Ma) in the North Atlantic/Mediterranean region, with later (middle Miocene, approx. 16–11 Ma) dispersal events to the South Atlantic and South Pacific. Contrasting with other pinnipeds, the fossil record of phocids from the North Pacific region is scarce and restricted to the Pleistocene. Here we present the oldest fossil record of crown phocids, monachines (monk seals), from the North Pacific region. The specimens were collected from the upper Monterey Formation in Southern California and are dated to 8.5–7.1 Ma, predating the previously oldest known record by at least 7 Ma. This record provides new insights into the early biogeographic history of phocids in the North Pacific and is consistent with a northward dispersal of monk seals (monachines), which has been recognized for other groups of marine mammals. Alternatively, this finding may correspond with a westward dispersal through the Central American Seaway of some ancestor of the Hawaiian monk seal. This record increases the taxonomic richness of the Monterey pinniped assemblage to five taxa, making it a fairly diverse fossil assemblage, but also constitutes the oldest record of sympatry among all three extant pinniped crown clades.

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