SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ef619f594fd3b3804ba048cedabfab2ab9c43d5a69dd7805d904197ef286d779' 
  AND token = 'wVsLTDrUhL/XTu8dbgeA364FJdc8X3/tD6eYfXKraHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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