Catalogue of the hymenopterous insects collected at Sarawak, Borneo; Mount Ophir, Malacca; and at Singapore, by A. R. Wallace. Author Smith, F. text Journal of the Proceedings of the Linnean Society of London, Zoology 1857 2 42 88 http://antbase.org/ants/publications/2588/2588.pdf journal article 2588 3. Megachile umbripennis , Smith, Cat. Hym. pt. 1. p. 175. Hab. Borneo (Sarawak) and Nepaul.