Key to species of Lamprothamnium in the Northern Territory

1 Dioecious (antheridia and oosporangia on different plants)............... ..................................................................................... L. stipitatum Monoecious (antheridia and oosporangia on the same plant)..........2

2 Oosporangia inside and outside the base of the whorl, frequently stipitate........................................................................ L. capitatum Oosporangia inside the base of the whorl only, not noticeably stipitate...................................................................... L. compactum