Supporting evidence for Delphinus delphis bairdii to supercede Delphinus capensis in the Pacific Ocean. Link https://marinemammalscience.org/science-and-publications/list-marine-mammal-species-subspecies/

"Previous editions of this list recognized two globally distributed species of common dolphins: the short-beaked common dolphin D. delphis and the long-beaked common dolphin D. capensis as proposed by Heyning and Perrin (1994). However, evidence that D. capensis thus considered is a polyphyletic taxon has been accumulating for some time. The long-beaked condition is apparently a convergent character state induced by regional ecology. In some regions, long-beaked common dolphins are genetically more closely related to short-beaked common dolphins than to long-beaked common dolphins in other regions (e.g., see Natoli et al. 2006). Cunha et al. (2015) summarized the relevant data and analyses, along with additional molecular data and analysis, and recommended that Delphinus capensis not be further used as proposed by Heyning and Perrin (1994). That recommendation is followed here. Cunha et al. (2015) noted that because the sympatric/parapatric long-beaked and short-beaked common dolphins off California in the Eastern North Pacific (ENP) appear not to interbreed, perhaps the ENP long-beaked common dolphins might be recognized as a separate species D. bairdii Dall,1873 (as advocated by Banks and Brownell (1969) based on the long-beaked condition). However, the molecular analysis for the ENP (Rosel et al. 1994) did not include common dolphins from the contiguous regions to the south in the eastern tropical and eastern South Pacific. Pending a more complete global review and revision of the common dolphins, the long-beaked ENP form is considered here provisionally as a subspecies D. delphis bairdii following the usage of Hershkovitz (1966). Delphinus capensis Gray,1828 from South Africa remains in the synonymy of Delphinus delphis Linnaeus,1758. The long-beaked common dolphin of the Indian Ocean is retained as a subspecies D. delphis tropicalis."

Other links, supporting evidence.

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0140251

https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=1116972#null

D. d. bairdii Dall, 1873. Eastern North Pacific long-beaked common dolphin

Consolidating with https://www.inaturalist.org/flags/554120