what is the head like of these species?
Elongated head
Cetacea
Whales have an elongated head, especially baleen whales, due to the wide overhanging jaw. 
what is baleen whale? A parvorder of the infraorder Cetacea. what is the lifespan of the latter mentioned? Over 200 years.
wiki:1624930
Cetacea [SEP] Head
Whales have an elongated head, especially baleen whales, due to the wide overhanging jaw. Bowhead whale plates can be long. Their nostril(s) make up the blowhole, with one in toothed whales and two in baleen whales. The nostrils are located on top of the head above the eyes so that the rest of the body can remain submerged while surfacing for air. The back of the skull is significantly shortened and deformed. By shifting the nostrils to the top of the head, the nasal passages extend perpendicularly through the skull. The teeth or baleen in the upper jaw sit exclusively on the maxilla.