SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00e22fc91b160a112abe118f52d65111ed9ffc98d782821769d5cd264c2273a0' 
  AND token = 'SN3g+sinegB0XoLi95bcUW269SDQXv81JGqUOSC6p6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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