Wilhem de Haan (1801-1855)
He was a Dutch zoologist who was born in Amsterdam and specialised in the study of insects and crustaceans. He became the first keeper of invertebrates at the Rijksmuseum in Leiden. He retired in 1846 after he was partially paralysed by a spinal disease and died in Leiden at the age of 54. As an early worker on mantids his work published in 1842 (in Latin & Dutch) is significant and the species he described are wonderfully illustrated. The mantis genus Haania is named after him, as is the phasmid genus Haaniella.
Reference
Haan, W. de (1842) Bijdragen tot de Kennis Orthoptera. in C.J. Temminck, Verhandelingen over de natuurlijke Geschiedenis der Nederlandsche overzeesche Bezittingen. volume 2.