SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ec814b7964ba2fd1e1595209d1cbf2b12975487ca417772fd8ee7e400e93b2bf' 
  AND token = '9/33o1pIwvuVkWYoUbzXDSB+ErluQxCXMRcQOmpJpE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

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