The genus Xenophya Schott (Araceae)

Up to the present time Xenophya has been a monotypic genus known only from its type collection. It is closely related to the genus Alocasia from which it may be distinguished by its entirely persistent spathe and anatropous ovules. In Alocasia the upper part of the spathe quickly withers and is lost and the ovules are suborthotropous. Schott (Bonplandia 10, 1862, 148) described a Philippine plant as ‘Alocasia? (Schizocasta) portei’. Schizocasia cannot be considered as validly published here because the author did not accept the name (Art. 34, ICBN). Xenophya Schott (1863) was published by Schott and placed in the tribe Zomicarpeae of the subfamily Aroideae. Engler (in DC., Monogr. Phan. 2, 1879, 495) included Schizocasia portei as representing a monotypic genus but changed his mind in the Additamenta on page 645 and transterred the species back to Alocasia. Again, ‘Schizocasia’ was not validly published because the author did not accept the name. In the same publication Engler (p. 526—7) accepted Xenophya in the Zomicarpeae but expressed his great uncertainty about the placement of the genus. The genus Schizocasia was finally established by Engler (Bot. Jahrb. I, 1880, 185—6) based on a Papuan species, S. acuta. In this publication Engler comments how similar his plant is to Xenophya but it differs by the micropyles of the ovules of Schizocasia facing out and facing in in Xenophya. Finally, Engler (Pflanzenr. Heft 73 1920, 60) continued the placement of Xenophya in the Zomicarpeae but said in a note that it would be better placed in the Colocasioideae (where Schizocasia is placed). In the same publication Engler (Pflanzenr. Heft 71, 1920, 115) in his discussion of Schizocasia said that Schizocasia appears to be very similar to Xenophya but differs in the facing of its ovules and above all in its staminate flowers.