SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2757c1adb9c24b679256e266f1f529217d16d3689fcd47c1cf85b94e0f3f2f9b' 
  AND token = 'NkCUk3hStMYnF8JBBWgBkjZ0hZu1hy4lJmm69e16kPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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