SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '933a3c42d08f5682deeff9317949d8ef672b2804708db6c1763891f93c2ee8ca' 
  AND token = 'hvtLUiqFav0pAzUQIURIsgxI+KqgytFRFN6mT159j8E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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