SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9dc424591cae2d93175bd34b48bef3d1d792549ad4a3258727fb9ec5dd8f8a9c' 
  AND token = 'za3e3CcrEiyM/+NjxCTzel5WWvIYnBbaqXAtmgPRqMo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE Impossible WHERE noticed after reading const tables