SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ff5a1583c72cbde4ee9244ebedcac8f0b1543fe57ecc79ecdf7690c0c5da10a' 
  AND token = 'n4+auahIYBmJAnCc3OTQHY3WUBkbF/ib4l+zBNQqguI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00011

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