SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cee7c19b80df1d4d09fa15fe7073f14ae789c57b36680528cd022962b33e05bc' 
  AND token = 'XBoDqDJTcmbKRF4oPdTbosficPffJeaL1l0frBuSTLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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