(S (S (NP (QP (ADVP (IN At) (JJS least)) (NN ten)) (NP (BASENP (JJR more) (NNS species)) (PP (IN of) (BASENP (NNS plants))))) (VP (VP (VBP are) (VP (VBN believed) (S (VP (TO to) (VP (VB be) (BASENP (JJ new) (NNS species))))))) (CC but) (VP (VBP are) (VP (ADVP (RB still)) (VP (VBG being) (VP (VBN studied))))))) (PERIOD .))