SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe3009b272c0b8cbb0e3d2a944c919aed21116c321b6dbbb89467358ec110ea9' 
  AND token = 'Vc0o7JPNJXd1N73oGZJ6OcZqNuasuyT+qCx8QTpGzPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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