The loach tribe Yunnanilini from China is reviewed here using morphological characters and complete mitochondrial genomes of select species. Molecular data suggest that the tribe Yunnanilini is not monophyletic and can be divided into three clades. Species of the
Yunnanilus nigromaculatus
group form an independent genus and are placed in
Eonemachilus
. In the phylogenetic tree,
Y. jinxiensis
clusters with
Paranemachilus genilepis
, and
Y. pulcherrimus
clusters with
Micronemacheilus cruciatus
, indicating that
Y. jinxiensis
and
Y. pulcherrimus
belong to
Paranemachilus
and
Micronemacheilus
, respectively. Based on morphological data,
Y. bailianensis
and
Y. longibarbatus
are placed in
Heminoemacheilus
, while
Y. jinxiensis
and
Y. pulcherrimus
, are placed in
Paranemachilus
and
Micronemacheilus
, respectively.
Yunnanilus niulanensis
and
Y. qujinensis
are treated as junior synonyms of
Eonemachilus caohaiensis
.
Eonemachilus
,
Micronemacheilus
, and
Yunnanilus
are show short separation between anterior and posterior nostrils. The genera can be distinguished from each other by mouth structure, lateral line and cephalic lateral-line canals, and papillae on median part of both lips. The anterior and posterior nostrils of
Heminoemacheilus
and
Paranemachilus
are closely set.
Paranemachilus
and
Micronemacheilus
are distinguished by cheeks covered with scales and lips with papillae, respectively. Our phylogenetic tree and morphological characters support
Traccatichthys
as a valid genus, which can be distinguished from
Micronemacheilus
by anterior and posterior nostrils closely set (vs. clearly separated). Four species are placed in
Traccatichthys
.