SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '550ee119909ab9a464f1db7c263ca6e65e45ae9251c7a06890736e42feb37824' 
  AND token = 'yW/nszZmLwHdRhGPwB6pJSDfuvh/LgH0/o4Zdp1/WD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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