SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ac560f3ea214f22550dbe3ce2ea514f3147a6651b968089a17321441fa14263' 
  AND token = 'S67aooejqsjizqnktSJiv42Y1O59E3vrOLi7oONKLkc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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