Baminornis (meaning "Fujian Province bird") is an extinct genus of basal avialans from the Late Jurassic (Tithonian age) Nanyuan Formation of China. The genus contains a single species, Baminornis zhenghensis, known from a partial skeleton. Baminornis was initially identified as the oldest known avialan to bear a fused pygostyle, but later research cast doubt on the identification of this structure, claiming it could instead be part of the synsacrum.
Baminornis (meaning "Fujian Province bird") is an extinct genus of basal avialans from the Late Jurassic (Tithonian age) Nanyuan Formation of China. The genus contains a single species, Baminornis zhenghensis, known from a partial skeleton. Baminornis was initially identified as the oldest known avialan to bear a fused pygostyle, but later research cast doubt on the identification of this structure, claiming it could instead be part of the synsacrum.
== Discovery and naming == The Baminornis holotype specimen, IVPP V33259, was discovered in outcrops of the Nanyuan Formation ('layer 2') near Yangyuan Village of Zhenghe County in Fujian Province, China. The specimen is incomplete and partially articulated, comprising bones of the left forelimb, and hindlimb, partial left pectoral and pelvic girdles, dorsal and caudal vertebrae, the pygostyle, and several ribs and gastralia.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).