At the press conference the fossil was described as the "missing link" in human evolution.
Because the fossils are not fully described yet, available character information that can be used in cladistic analyses is limited.
Troodontid fossils were among the first dinosaur remains described.
The fossil was not formally described until 2010 when its discovery was announced in the journal Nature.
Complete skulls and postcranial fossils have since been described.
The two other fossils, belonging to one species, were described shortly after their discovery in the 1970's.
Other fossils found at Santa Rosa have not been described in detail.
When this occurs the fossil is described as a "reworked fossil".
The fossil has been described as being a 71 cm (28 in), nearly intact skull.
The fossils were described as a new species, Dolichorhynchops herschelensis.