Silky sifaka (Propithecus candidus) are among the worlds most endangered primates, with less than 1000 remaining in the wild. Native to the steep, mountainous rainforests of northeastern Madagascar, silkies, as they are often called, make ‘zzuss’ vocializations. Sounding like a combination of a sneeze, a lip smack, and sifaka, these calls act as both alarm calls and to help group members maintain contact with each other. 

[Photo and caption by Meredith Lutz]

References:

Patel, E. R., & Owren, M. J. (2012). Silky sifaka (Propithecus candidus) “zzuss” vocalizations: Sexual dimorphism, individuality, and function in the alarm call of a monomorphic lemur. The Journal of the Acoustical Society of America, 132(3), 1799-1810.