The endemic Anoplocnemis madagascariensis (Coreidae - tribe Mictini) closely resembles Anoplocnemis curvipes which is widely distributed throughout Africa, black and about 3 cm long.
Anoplocnemis madagascariensis is greyish brown and smaller but otherwise similar in form.
Males (last photo) have a single large spine on each hind leg; females lack this.

Dr. Harry Brailovsky, an entomologist at UNAM (Universidad Nacional Autónoma de México) and world expert on Coreidae helped me identifying this species.

Andasibe-Mantadia National Park, Madagascar, 11, 13 & 14 January 2014