Silvabestius undetermined

† Silvabestius

SPECIES SCORED: † Silvabestius johnnilandi (type species), † S. michaelbirti.

GEOLOGICAL PROVENANCE OF SCORED SPECIMENS: Hiatus South Site (Riversleigh Faunal Zone A) and VIP Site (Riversleigh Faunal Zone A or B), Riversleigh World Heritage Area, Queensland, Australia.

AGE OF SPECIMENS SCORED: Riversleigh Faunal zones A and B are interpreted as late Oligocene and early Miocene respectively, based on biostratigraphy (see above). We have assigned the entire age range of the late Oligocene to early Miocene (Chattian to Burdigalian; Cohen et al., 2013 [updated]) for this taxon.

ASSIGNED AGE RANGE: 27.820 –15.970 Mya.

REMARKS: Two species, † Silvabestius johnnilandi and † S. michaelbirti, were described by Black and Archer (1997a) based on specimens from the VIP and Hiatus South sites. The VIP Site has been identified as part of Riversleigh Faunal Zone A, but may in fact belong to Faunal Zone B (K.H. Black, personal commun.). Both species are represented by relatively complete cranial material (e.g., the holotype of † S. jonhnnilandi is a well-preserved juvenile skull), but only dental descriptions of these specimens have been formally published to date (Black and Archer, 1997a); however, the unpublished thesis of Black (2008) includes cranial descriptions. We used this Riversleigh material of both species to score a composite † Silvabestius terminal.