SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2ae7c72119e5d9db89090061ffb6d44668f7196b4f5235eae272fdc86f45fc47' 
  AND token = 'QTM9tx/xa/5ZT+vFJhiFnY8kTaqPU23MtKn7K53w8fg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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