SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '452a35f68e4aa8ecda95b6454d0dbe019db799023d40d94200a3c91884e6ab01' 
  AND token = 'RomL7yiHBVrzuNqS4mRjZfDpfFdl6mIYgV3VhBvVFeA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}