SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f673a6f642b5eeab7f2957f3833119690077f976ff71ab55c5c5328d22ef23e4' 
  AND token = 'plKYE9+GcjJd1d2f0EjsSQX8kv0QGMWozLZ1mHKifII=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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