SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be5ee1c335fe7675cdc4c9109f28dc07420838b45eaef0ffe7f21dfbab28ca79' 
  AND token = 'wKYvnHtzsx6Q5ZC01A/TqKFVx7xJLxHG5N5g6Un1w5k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}