Marshall (1942) Glauclerum brasilianum Lake Olmaga Often heard late at night esp. moonlit nights on W side lake where mixed veg. including very large trees. Usually paired - a high & a low voice calling near, together sometimes in same tree. Coll. one in growth approaching swamp forest type. A pair often heard up dry wooded ridge above the lake. One morning saw two in broad daylight flying from one small "mimosa" (some kind of leguminous small nated tree) to another in grassy area on S side lake. I Pairs here, habitat extremely varied San Ignacio One seen in evening by Stirton & Garley daytime