SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6d59aea1832251299cee2438590df446f6e72e74849b8b8d3b352fddc23cef8f' 
  AND token = 'RSuEuE/wyVH0hgrj7DTV2mcALpAVfvsQk61i7qvukrY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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