Why doesn't reflection work when a class returns Lambdas

I have encountered a somewhat strange behaviour. I use annotations to mark certain classes with a particular purpose, and then I use org.reflections library to find all the classes with the particular annotation. However when a class implements a method that returns a lambda function, the reflection won't find the annotated class anymore. The signature of the class is unchanged.

Example of annotation:

@Retention(RetentionPolicy.RUNTIME)
public @interface MyAnnotation {
   String someValue();
}

Using the annotation:

@MyAnnotation(someValue = "a")
public class FooBar extends BaseClass {

    @Override
    public Consumer<Integer> doSomething() {
        return null;
    }
}



@MyAnnotation(someValue = "bazbar")
public class BarClass extends BaseClass {

    @Override
    public  Consumer<Integer> doSomething(){
        return (x) -> {};
    }
}

Finding the annotations

private static final Reflections reflections = new Reflections("com.mypackage");

Set<Class<?>> clazzes  = reflections.getTypesAnnotatedWith(MyAnnotation.class);

Now - the set 'clazzes' only contains 1 single class, the FooBar class. If I remove the lambda return value from the BazBar class that one too shows up, but as soon as one method in the class returns a lambda the reflection wont work.

I'm lost, any ideas?