SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '250177d30e7711644e16cd488f2fa6c7d6b401b529715796411dc23383175e97' 
  AND token = 'Yyvepairob8sWZNuG82Ucr/tr2TOTyabdgH/Ql6FrgA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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