SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22768c367e18dba30b12aeacfd46435225a1db5e535283068a58488cf36069c7' 
  AND token = 'x7XAmntbqrfsL9rvz1Nq6ruMpFjRXNfPVL0jjtyaeBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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