SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f27d620949fcd3b75dd44f9001b8bd838e4e4aa0c2d0855966f29586f1a04bc3' 
  AND token = 'OwOP3/wyeQXNM24Btft09MSPD9vZ7NNmyhzWfwKRYvo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

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