SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cde095dd2f2eb126c35e17647ff3a58d2e9421c09417b74f4b92f35d6afddacf' 
  AND token = 'qhXfuc6/pyJwSxfwUDzO+FAzj07+RnOd6RECPOn+3ws=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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