Maskal Daisies/Coreopsis

According to my holiday calendar,

http://www.schooloftheseasons.com/sept.html

in Ethiopia people celebrate Holy Cross on September 27 by building huge structures of logs, set up like teepees, decorated with yellow Maskal daisies and burnt at night. I found one web site which also refers to this festival and mentions the daisies:
http://my.ort.org.il/givatram/etiopia/TRGIL7.HTML

But what are they? A quick Google search produces only one reference to maskal daisies in a scientific paper called “Medicine in Ethiopia” by C. S. Leithead in which he says they are Coreopsis boraniana. I’ve not been able to find this species mentioned in any of the articles on Coreopsis but it seems likely that the daisies are Coreopsis which likes to grow in hot, dry climates and blooms through November, even in the soggy Northwest. The one thing that makes me wonder if this is the same plant is that most of my references say that Coreopsis is native to North America.

The name Coreopsis comes from the Greek word koris which means Bedbug because the seeds look like small black bugs. It’s also called Tickseed for the same reason. But the flowers look like cheerful yellow daisies, with toothed petals, and they are members of the Aster family. They are sometimes also called Calliopsis, according to Wikipedia.
http://en.wikipedia.org/wiki/Tickseed
Askwith says that Calliopsis is the name for the annual form while Coreopsis applies to the perennial version of this plant.

Paghat, as usual, has some lovely photographs of Coreopsis growing in her Northwest garden and useful accounts of how it grows
http://www.paghat.com/coreopsis.html

Chelsie VandaVeer has written a poetic description of Coreopsis which is illustrated with a lovely photograph of the flowers of Coreopsis leavenworthii which grows in damp places in Florida::
http://www.killerplants.com/plant-of-the-week/20011001.asp
Her description of coming upon a field of golden Coreopsis echoes the description about the Ethiopian festival when “the meadows are yellow with the brilliant Maskal daisy.”

References:
Askwith, Herbert, editor, The Complete Guide to Garden Flowers: An Encyclopedia of Garden Planning, A.S. Barnes and Company 1961
Levine, Donald, Wax and Gold: Tradition and Innovation in Ethiopian Culture, University of Chicago Press, 1965, p. 62
Perl, Lilia, Ethiopia: Land of the Lion, William Morrow 1972, pp.72-3

Photograph:
Coreopsis lanceolata from J.S. Peterson @ USDA-NRCS PLANTS Database