Crossandra Salisb.

Daniel, Thomas F., 2018, Chromosome Numbers of Some Cultivated Acanthaceae with Notes on Chromosomal Evolution in the Family, Proceedings of the California Academy of Sciences 64 (9), pp. 319-332 : 321

Crossandra Salisb.

— Crossandra consists of about 45 species native to Africa, Madagascar, Arabia, India, and Sri Lanka. Our count of n = 19 for C. infundibuliformis (L.) Nees ( Fig. 1E ), a species occurring in both Africa and the Indian Subcontinent, agrees with nine of the 11 previous counts for this species (sometimes reported as C. undulaefolia Salisb. ). The other two counts for this species are both n = 30, and possibly represent counts for a morphologically similar taxon, C. nilotica Oliver , which is often misidentified, and for which n = 30 has been reported and confirmed (see Daniel and Chuang 1998). Counts have been reported for two other species of Crossandra , C. flava Hook. and C. pungens Lindau , both of which are n = 21 (Daniel and Chuang 1998). De (1966) suggested x = 10 as a basic number for Crossandra . This number is not currently known among species of the genus, but based on counts reported to date for four species, it seems possible and would indicate both polyploidy and dysploidy among species.

Figures

FIGURE 1 (upper right). Chromosomes of Acanthaceae in pollen mother cells. A. Dyscho- riste thunbergiiflora, metaphase II (only half of cell shown), n = 15. B. Brillantaisia owariensis, telophase I, n = 16 (with one lagging chromo- some toward “upper” pole). C. Brillantaisia owariensis, metaphase I, n = 16. D. Ruellia ele- gans, diakenesis (showing nucleolus, n), n = 17. E. Crossandra infundibuliformis, metaphase I, n = 19. F. Ruellia dipteracanthus, metaphase I, n = 17. G. Justicia scheidweileri, metaphase I, n = 14. Chromosomes shown in outline only are touching or overlapping other chromosomes. Scale applies to all figures. See Table 1 for voucher information.