SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '023a68f706993f5f7394e70c75dc099e1cab26cee76f1f0ad179f658a9326eb3' 
  AND token = 'h8/Siz3NccO73PVbxtvahIF758KCVWYDP/q97zTFoew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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