species, North America, South America, Caribbean Islands, Europe, Africa, Asia.
limits of Andrachne have been broadened in recent years by some authors
(Govaerts et al., 2000) to include the 10–25 species of Leptopus
Decne., which occur from Asia south to Australia. Andrachne in the
strict sense is mostly Mediterranean with a few species in North America, one
of which also occurs disjunctly in portions of western South America. The two
groups have been said to differ in a few relatively subtle characters such as
details of ovule placentation. Molecular studies (Wurdack et al., 2004) have
reinforced the relationship between the two groups but have not been able to
resolve the controversy over generic limits thus far.