Refer to the passage below and then answer the question afterwards in the same language as the passage:

Passage: Christian von Steven (Russian: Христиан Христианович Стевен - Khristian Khristianovich Steven; 19 January 1781, in Fredrikshamn, Finland – 30 April 1863, in Simferopol, Crimea) was a Finnish-born Russian botanist and entomologist.

Question: When did von Steven die?
30 April 1863