User:JeanGeilland/Zaluzianskya

Zaluzianskya

Zaluzianskya dentata. Illustration from Marloth [1].

Zaluzianskya is a genus of flowering plants now regarded as being a member of the Scrophulariaceae, the figwort family. The genus is endemic to Southern Africa and includes some sixty species described at the time of writing. [2]

Superficially the shape of the flowers is strikingly phlox-like, so much so that some WWW entries listed in google at the time of writing call Zaluzianskya ovata “Night Phlox”. Phlox however, is a genus in the family Polemoniaceae, not closely related to Scrophulariaceae.

According to the Royal Horticultural Society [3] Zaluzianskya was named in honour of Adam Zaluziansky von Zaluzian, 1558-1613, a physician of Prague, author of Methodus Herbariae, 1592.

Zaluziansky seems to have been a deservedly prominent botanist in his day, with some views on taxonomy quite advanced for his time. [4] It seems something of a pity that he never lived to to know the honour of having a genus named after him, nor probably ever saw any plants in that genus, since almost certainly none were known in Europe during his lifetime. (The Cape of Good Hope was settled by the Dutch in 1652, some 39 years after his death, and the genus, though attractive and interesting for various reasons, is neither spectacular nor conspicuous.)

The following technical description of the genus is adapted from “The Genera of Southern African Flowering Plants” [5]

Genus ZALUZIANSKYA. F.W. Schmidt in Neue Selt. Pfl. 11 (1793); name proposed for conservation, J. Paclt in Taxon 21:539 (1972); Hiern in FC. 4, 2: 333 (1904). Annual or perennial herbs, more or less viscid and usually turning black in drying. Leaves simple, toothed or entire, opposite near base, upper alternate. Flowers in terminal spikes or sometimes axillary, variably bracteate. Calyx bilabiate or 5-lobed; tube more or less cylindric; when bilabiate then one lip 3-lobed and other 2-lobed, usually membranous, more rarely somewhat leathery, 5-ribbed, sometimes 2- or 5-winged, persistent. Corolla 5-lobed, regular or bilabiate; tube long-cylindric, eventually splitting at base. Stamens normally 4, didynamous, sometimes 2, rarely 5, often subsessile, inserted in mouth and/or corolla-throat. Ovary linear-lanceolate to ovate, 2-locular, with many ovules, with a conspicuous, terete gland or small, globose swelling at base, glabrous; style usually filamentous, included or exserted, with linear stigma. Fruit an ovoid capsule, with bifid valves and septicidal dehiscence; seeds more or less 4-sided, with whitish testa.


Although the genus has a certain charm, Zaluzianskya species have not been of horticultural significance until fairly recently, but lately some nurseries have been advertising a few species on the World Wide Web. The attractions appear to have been the elegant phlox like shape of the petals, the delicate, but often showy, colouration, and the fact that certain species, such as Zaluzianskya ovata, have a strong, pleasing fragrance after dark. No doubt larger, showier varieties will appear within the next few years.

The subject of night-scented flowers is one aspect of a field of ecological and evolutionary research in which the genus Zaluzianskya is proving to be of special interest. The fragrance after dark suggests that in nature the species in question are pollinated by moths, whereas day-pollinated species often have little or no obvious scent. At the time of writing research is in progress on the ecological and evolutionary relationships between some members of the genus and specialist long-tongued pollinators, particularly night flying hawk moths (Family Sphingidae) and flies in the families Nemestrinidae, Tabanidae, and Bombyliidae [6] [7] [8] Day-flying hawk moths, such as the genus Macroglossum (Hummingbird Hawk Moths) also seem to be significant pollinators of many species of Zaluzianskya.

The mutual adaptation and specialisation between insects and this genus of flowers is a complex and currently fruitful field of evolutionary study. This is not limited to just the genus Zaluzianskya of course. Southern Africa has many unrelated genera of flowers with similarly developed long corolla tubes, pollinated by such flies and moths. The flower genera include Gethyllis, Struthiola, and various genera of the Iridaceae. The fact that the adaptations are sympatric and functionally analogous has inspired several lines of evolutionary research.

The members of the genus Zaluzianskya vary greatly in the field. Compare the illustration from Marloth with these tiny unidentified species from Vaalputs in South Africa, a very arid area where some ephemerophytes have inflorescences larger than the parent plant. In these two species the inflorescences are somewhat less than 50 mm across.


The following species was larger, photographed in less arid conditions near the Sterkfontein caves. It was about 40 cm high.

References

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  1. ^ Marloth, Rudolf. “The Flora of South Africa” 1932 Pub. Capetown: Darter Bros. London: Wheldon & Wesley.
  2. ^ Arnold T.H., de Wet B.C. (Eds), Plants of Southern Africa: Names & Distribution, MEMOIRS OF THE BOTANICAL SURVEY OF SOUTH AFRICA No. 62, Pub.National Botanical Institute, South Africa.1993 ISBN 1-874907-03-X
  3. ^ CHITTENDEN, FRED J. Ed., Royal Horticultural Society Dictionary of Gardening, Oxford 1951
  4. ^ Debus, Allen G., Man and nature in the Renaissance, Cambridge 1978 ISBN: 0-521-29328-6
  5. ^ Dyer, R. Allen, “The Genera of Southern African Flowering Plants”. ISBN 0 621 02854 1, 1975
  6. ^ Picker, M., Griffiths, C., Weaving, A. Field Guide to the Insects of South Africa, Struik 2003. www.struik.co.za
  7. ^ Bruce Anderson, Steven D. Johnson, J. Kohn, The Geographical Mosaic Of Coevolution In A Plant–Pollinator Mutualism, Evolution, Jan 2008 : Vol. 62, Issue 1, pg(s) 220-225
  8. ^ S. D. Johnson, . J. Edwards, . Carbutt and C. Potgieter. Specialization for hawkmoth and long-proboscid fly pollination in Zaluzianskya. Botanical Journal of the Linnean Society, Vol 138 pp 17-27 March 2002