SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '20f3fd5a42ae02df8f326eaa25543608631cdf3cce4b8a7c3581ff0565a70508' 
  AND token = 'YhGS/XhwsegC5uk9mZRi8gpb6ZYsm20016/vcX70xzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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