Minicrania

Minicrania ("small skull") is an extinct genus of tiny antiarch fish, with armor averaging up to about 2 centimetres (0.79 in) long, which lived during the Lochkovian epoch in Early Devonian Yunnan Province, China and northern Vietnam.

Anatomically, Minicrania bears a strong resemblance to the Yunnanolepiformids (i.e., Yunnanolepis and Chuchinolepis).[2] However, other anatomical features, especially the head-width ratios, separate it from the Yunnanolepiformids. Zhu and Janvier regard it as the sister taxon of the sinolepids and the Euantiarchi (i.e., the bothriolepids and the asterolepids), representing a transitional form between the Euantiarchi and the more primitive Yunnanolepiformids.

There are two recognized species. The type species, M. lirouyii, is found in Lochkovian-aged strata in Qujing, Yunnan, and is characterized by the presence of numerous tubercles covering the dermal surface of the armor. The specific name honors a Mr. Li Rou-yi, who assisted in collecting the first specimens. The second species, M. lissa,[1] is found in Lochkovian deposits in northern Vietnam, near the Chinese border. M. lissa's tubercles are comparatively very small and ill-defined, if present, hence the specific epithet "lissa" meaning "smooth." Otherwise, the armor is very similar, if not identical to that of M. lirouyi.