SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17bb3d68ec60d1e33309a4d31919a386f8446e4a12faed2c10d11c3fbff82f19' 
  AND token = 'DOzVXk9l641k8b84OyV2LFg5WLHmYlxLq8gSXlH5OdY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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