|Feresea... maybe. This species can be distinguished from Pseudorca by having a proportionally larger dorsal fin (2 base lengths away from the blowhole vs. 2.5) and by having a clearly demarcated cape; Peponocephala can be distinguished by having pointed flipper tips, a pointed head when viewed from above, and no white extending around the face (Baird 2010). I think this is the case in the above photo, but I'm not entirely certain. Photo by Gary L. Friedrichsen from WoRMS.|
In 1965 - a little over a decade after the external appearance of the animal became known - Feresa was held in captivity. Pryor (1991) remarked that one individual behaved "more like a wolf than a normal dolphin" would "growl and snap like as canid" and "not hesitate to attack people and other cetaceans". Since when are cetaceans capable of growling? This behavior has led some to presume that Feresa preys on mammals in the wild (Leatherwood et al. 1982) and aggression towards other dolphins has been observed whilst individuals were trapped in tuna seines (Reeves et al. 2002). Considering that both situations occurred in cramped and undoubtedly stressful environments, I think it is completely unfounded to conclude that Feresa is a pugnacious marine mammal-killing macropredator with the available evidence. Stomach contents have included squid and fish (Rodríguez-López and Mignucci- Giannoni 1999; Zerbini & Santos 1997)
|Feresa skeleton. From Wikipedia Commons.|
Baird, R. W. (2010). Pygmy Killer Whales (Feresa attenuata) or False Killer Whales (Pseudorca crassidens) Identification of a Group of Small Cetaceans Seen off Ecuador in 2003. Aquatic Mammals 36(3), 326-327. Available.
Gray, J. E. (1871). Supplement to the Catalogue of seals and whales in the British Museum. Available.
Leatherwood, S., Reeves, R. R., Perrin, W. F., & Evans, W. (1982). Whales, dolphins, and porpoises of the eastern north pacific and adjacent arctic waters (NOAA Technical Report NMFA Circular 444). Washington, DC: U.S. Department of Commerce, National Oceanic and Atmospheric Administration, National Marine Fisheries Service. Partially Available.
McSweeney, D. J., Baird, R. W., Mahaffy, S. D., Webster, D. L., and Schorr, G. S. (2009). Site ﬁdelity and association patterns of a rare species: Pygmy killer whales (Feresa attenuata) in the main Hawaiian Island. Marine Mammal Science 25(3), 557-572. Available.
Pryor, K. (1991). Mortal remains: Studying dead animals. In: Pryor, K. & Norris, K. S. (eds.) Dolphin Society: Discoveries and Puzzles. University of California Press: Berkeley. Available.
Reeves, R. R., Stewart, B. S., Clapham, P. J., & Powell, J. A. (2002). National Audubon Society Guide to Marine Mammals of the World. Alfred A. Knopf: New York.
Rodríguez-López, M. A. & Mignucci-Giannoni, A. A. (1999). A stranded pygmy killer whale (Feresa attenuata) in Puerto Rico. Aquatic Mammals 25(2), 119-121. Available.
Rossi-Santos, M., Baracho, C., Neto, E. S., & Marcovaldi, E. (2006). First sightings of the pygmy killer whale, Feresa attenuata, for the Brazilian coast. JMBA2 - Biodiversity Records. Available.
Slater, G. J., Price, S. A., Santini, F., and Alfaro, M. E. (2010). Diversity versus disparity and the radiation of modern cetaceans. Proceedings of the Royal Society B 277(1697), 3097-3104. Available.
Vilstrup, J. T., Ho, S. Y. W., Foote, A. D., Morin, P. A., Kreb, D., Krützen, M., Parra, G. J., Robertson, K. M., de Stephanis, R., Verborgh, P., Willerslev, E., Orlando, L., & Gilbert, M. T. P. (2011). Mitogenomic phylogenetic analyses of the Delphinidae with an emphasis on the Globicephalinae. BMC Evolutionary Biology 11(65). Available.
Zerbini, A. N. & Santos, M. C. O. (1997). First record of the pygmy killer whale Feresa attenuata (Gray, 1874) for the Brazilian coast. Aquatic Mammals 23(2), 105-109. Available.