Mikko's Phylogeny Archive Modern Avian Groups   Scopidae - hammercops

After Olson, 1985 and Sibley & Monroe, 1990

<==o Scopidae (hammercops; varjohaikarat)
   `--o Scopus (varjohaikarat)
      |-- †S. xenopus
      `-- S. umbretta (varjohaikara)

Reference(s):

Olson, S. L., 1985: The fossil record of birds. 79-239.
in Farner, D., King, J. & Parkes, K. (eds.), 1985: Avian Biology. vol VIII.
–Academic Press, New York. 1985.

Sibley, C. G. & Monroe, J., BL., 1990: Distribution and taxonomy of birds of the world.
–Yale University Press, New Haven & London, 1990. XXIV-1111.