Well, something like this:
TextureManager.getInstance().addTexture("alien", new Texture("alienskin.jpg"));
Object3D alien= Loader.loadMD2("alien.md2", 0.8f);
alien.setTexture("alien");
alien.compile(true);
alien.build();
alien.getAnimationSequence().remove(3);
alien.getAnimationSequence().remove(4);
alien.getAnimationSequence().remove(6);
alien.getAnimationSequence().remove(7);
// ....remove all unneeded sequences here...
new DeSerializer().serialize(alien, new FileOutputStream("alien.ser"), true);
You can then take that alien.ser file and load it on Android via the Loader-class. To figure out which animations you need, you can use any MD2 viewer...or write a simple one yourself.