New fossil remains of the commensal barnacleCryptolepas rhachianectiprovide evidence of gray whales in the prehistoric South Pacific

Abstract

We report the finding of two partial specimens of Cryptolepas rhachianecti (Cirripedia, Coronulidae), a coronulid barnacle known only to inhabit the skin of gray whales (Eschrichtius robustus), in Pleistocene-aged sediments from the Canoa Basin, Ecuador. While the historical range of gray whales includes the North Pacific and North Atlantic, to our knowledge this is the first inferred evidence of a gray whale population having resided within the South Pacific. We describe the two Cryptolepas rhachianecti fossils, use isotopic analysis to investigate evidence of migration in their host whales, and discuss their implications for our understanding of gray whale evolutionary history.

A forgotten cirripedological gem: a new species of whale barnacle of the genus Cetopirus from the Pleistocene of the United States West Coast

“…(Although Bosselaers & Collareta (2016) were hesitant about the genus-level assignment of C. murata , the high-quality photographs provided by Taylor et al . (2022) clearly confirm that this extinct species belongs to Cryptolepas .) Remains of C. murata co-occur with the holotype of C. polysyrinx sp.…”

“…2011; Hayashi 2012; Bosselaers & Collareta 2016; Taylor et al . 2022). (Although Bosselaers & Collareta (2016) were hesitant about the genus-level assignment of C. murata , the high-quality photographs provided by Taylor et al .…”

“…There is no hint, for this extinct genus and species, of what sort of host it might have been on. Cryptolepas murata was described from Upper Pleistocene deposits exposed at San Quintín, Baja California, Mexico, and is currently regarded as belonging to the same genus as Cryptolepas rhachianecti Dall, 1872, an obligate epibiont of grey whales (Eschrichtius robustus (Liljeborg, 1861)) (Newman & Abbott 1980;Bradford et al 2011;Hayashi 2012;Taylor et al 2022). (Although Bosselaers & Collareta (2016) were hesitant about the genus-level assignment of C. murata, the high-quality photographs provided by Taylor et al (2022) clearly confirm that this extinct species belongs to Cryptolepas.)…”