A Revision of Tribe Tinosporeae (Menispermaceae) in Asia, Australia and the Pacific: The Menispermaceae of Malesia and Adjacent Areas: XII

Abstract

As with some of the other tribes of Menispermaceae which are currently recognized, it is not easy to state the diagnostic features of the Tinosporeae. The main characters of the tribe are: drupe with style-scar terminal (at the opposite end from the base); condyle usually present (absent in Aspidocarya); endosperm present; seed usually straight (deeply cupular in Chlaenandra); embryo with thin divaricate foliaceous cotyledons. The latter character mentioned by Diels and earlier authors is very difficult to check in herbarium material: I have rarely been able to extricate the delicate embryo in a sufficiently intact state to examine it. It may be noted that the stamens, often 6, can be free or united into a peltate synandrium as in certain genera of Mllenispermeae (= Cocculeae). Diels (op. cit. 46) in his key to Tinosporeae stated 'Endocarpium rectum', which is not true for Chlaenandra where the endocarp is very similar in general form to that of Anamirta (Coscinieae) which Diels keyed out separately under 'Endocarpium curvatum'. In both these genera there is a deeply intrusive condyle around which the cup-shaped seed fits. An essential difference between the genera is that on the drupe of Chlaenandra, as in other Tinosporeae, the style-scar is remote from the base (i.e. they are at opposite ends). In Anamirta, however, the style-scar is close to the base as a result of differential growth of the pericarp, the dorsal side growing much more than the ventral side; at the same time the endocarp has undergone similar differential growth leading to its curvature and the invagination of the condyle. It appears that in Chlaenandra a similar development of the endocarp has taken place but without affecting the pericarp. Such independence of development between endocarp and pericarp, but in a different manner, is seen in Albertisia (Tiliacoreae, syn. Tricliseae) where the endocarp remains straight yet the pericarp is curved, bringing the style near the base.