Here are some pictures of arenaviruses. There aren't too many because there are only a few facilities in the world equipped to study them (Biohazard Level 4 family).

http://www.cdc.gov/ncidod/dvrd/spb/mnpages/dispages/arena.htm

Vero E6 tissue culture cell infected with an arenavirus (above). Image shows extracellular virus particles budding from the cell
surface. Magnification approx. 12,000 times. Image courtesy Cynthia Goldsmith, MS, Infectious Disease Pathology Activity, DVRD, NCID, CDC.

Le Guenno, B. Emerging Viruses, Scientific American, Oct. 1995.

False color electron micrograph of an arenavirus (above).Le Guenno, B. Emerging Viruses, Scientific American, Oct. 1995.