A modified classification of the family Asclepiadaceae R. Br. s.s. into three tribes – Secamoneae, Asclepiadeae s.l. and Stapelieae s.l. – is proposed. The position of attachment of the caudicles to the pollinia is suggested as a criterion for defining the erect and pendulous stature of the pollinaria. The concept of the transverse stature of pollinaria has been abandoned. In addition to the stature of the pollinaria, the morphology of the anther sacs (whether or not embedded in the tissue of the anther wings) and the position of anther wings with respect to the anther sacs are suggested as supplementary characters for tribal classification of the family. The characters of the gynoecium, particularly the presence or absence of true styles and the sharp constriction between stigma‐head and ovaries (i.e. clavuncular morphology) have also been suggested as useful in differentiating Asclepiadeae s.l. and Stapelieae s.l, along with the stature of the pollinaria. The circumscription of Asclepiadeae is emended to accommodate taxa of the former tribe Gonolobeae as a subtribe. The circumscription of Stapelieae has been retained in a wider sense, as suggested by Decaisne (1844). The tribes Fockeeae Kunze, Liede & Meve (1994), Marsdenieae Benth. (1876), Ceropegieae Benth. (1876), and Stapelieae s.s. sensu Benth. (1876; non Decne., 1844) have been relegated to subtribe status in the tribe Stapelieae Decne. (1844). Homology of the different parts of the gynoecium in the Asclepiadeae (s.l.) with those in the Stapelieae (s.l.) has been drawn. Segments of the style have been distinguished into ‘true style’ and ‘pseudostyle’, the former as parts of the ovary segment in development, the latter as stigma segment in development. The genus Tybphora R. Br. which was formerly treated under Stapelieae Decne. has been transferred to Asclepiadeae based on the morphology of the pollinaria, gynoecium and seed coat architecture.

Heterostemma Wight & Arn. (Asclepiadaceae) and a new species from India. Heterostemma vasudemni Swarupanandan & Mangaly, a new species belonging to Asclepiadaceae is described and illustrated. The discoid‐urceoloate corolla and the staminal coronal scales with a ventral appendage show this species to be intermediate between the two genera Heterostemma and Oianthus. Basically, the concepts of the two genera differ only in a pair of characters which, in the light of the new species seem not to be particularly diagnostic. On this basis it is proposed to merge the two genera together, by reducing Oianthus as a section under Heterostemma. Consequently, three new combinations are proposed. Examination of recent collections extends the distribution of what was 0. decanense, earlier considered to be endemic to Maharashtra, further south to Kerala.

No abstract

MANGALY, J. K. & NAYAR, J. 1990. Palynology of South Indian Zingiberaceae. Light microscope studies on pollen morphology of 2 I Old World, tropical taxa of Zingiberaceae reveal that an exine is absent only in Kaempferia. A discontinuous cxine layer consisting of circular plates joined together at margins occurs in Alpinia galangu and Amomum hypoleucum while all other taxa possess an unintcrrupted exine layer which is commonly 0.7 pm to less than 2.0 pm thick (3.2 pm in zingiber zerumbet, 2.5 pm in Amomum hypoleucum). Exine is spinose in Alpinia (smooth in Alpinia sanderae), Amomum and Boesenbergia, verrucose in Elettaria, tuberculate to areolate or striate in <&giber, papillose in Glohha and smooth or nearly so in Curcuma, C h s t u~ arid Hedyhium. Pollen grains are spheroidal, 50-90 pm in size (35 pm in Gfobba ophioglossa), and inaparturate (foraminate in Costus), except in Curcuma and zingiber where they are ovoid to ellipsoidal, 70-135 x 60-80 pm in size and sulcate. A larnellated intine, much thicker than the exirie, orcurs in all, and it is thinner at the apertural region in Curcuma, Costus and xzngiber; in Eletlaria and Hedychium it is thinner in one or few large scattered circular areas, and in Boesenbergia and Alpinin zerumbet on one side of the grains.

A new species of Alpinia (Zingiberaceae). A. smithiae Sabu & Mangaly is described from Western Ghats of India. It is a member of section Alpinia subsect. Catimbium.