The Sharp-tailed Streamcreeper (Lochmias nematura) is a passerine bird of South America belonging to the family Furnariidae, the ovenbirds. It is the only member of the genus Lochmias.

This bird is about 6 in (15 cm) long, with a short tail and a long, thin, slightly curved bill. The plumage is dark brown, densely spotted white on the underparts. There is a white stripe over the eye and the tail is blackish. The song is an accelerating trill, lasting for about five seconds.

There are six subspecies which differ little:

• Lochmias nematura castanonotus - south-east Venezuela
• Lochmias nematura chimantae - southern Venezuela
• Lochmias nematura nelsoni - Panama (eastern Darién)
• Lochmias nematura nematura - south-east Brazil, north-east Argentina, eastern Paraguay, northern Uruguay.
• Lochmias nematura obscuratus - Peru, Bolivia
• Lochmias nematura sororius - Colombia, Ecuador, northern Venezuela, north-east Peru

It inhabits dense undergrowth near streams, particularly in humid premontane and montane forest, foraging on the ground for insects and other invertebrates. It usually occurs alone or in pairs and is often shy and hard to see. The nest is ball-shaped with a side-entrance and is built on the ground.