SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16c25032942534f54ea1a7036698820527d5b6ef981d7133124fcdd697d5501c' 
  AND token = 'OOVa7+IhytdBUxsjlL/lMOJHVZOBcFmw6zyyHbRxQK8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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