The number of florets per head appears to distinguish C. texana from C. carduacea. Additionally, fall & winter heads of both species have a greater number of florets than do spring heads. Even without adjusting for this seasonal difference there is minimal overlap: C. texana 91–155 florets vs. C. carduacea 31–107 florets. And, of course, the floret counts definitely distinguish both from the third Texas Chaptalia, C. tomentosa, reported to have ca. 60 florets (of which: peripheral ca. 20, inner pistillate ca. 5-11, central ca. 25) [Correll & Johnston, p. 1722].
|
|
C. texana |
C. carduacea |
||||||
|
|
Spring (n=3) |
Fall/Winter (n=4) |
Spring (n=9) |
Fall/Winter (n=5) |
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|
|
range |
avg. |
range |
avg. |
range |
avg. |
range |
avg. |
|
Peripheral pistillate |
22—27 |
25 |
22—36 |
30 |
12—22 |
16 |
(1—) 11—21 |
14 |
|
Inner pistillate, |
54—62 |
58 |
57—95 |
71 |
17—50 |
34 |
(24—) 44—74 |
56 |
|
Central perfect |
12—18 |
15 |
16—24 |
21 |
7—14 |
11 |
(6—) 12–16 |
12 |
|
total: |
91—106 |
97 |
95—155 |
121 |
36—85 |
60 |
(31—) 75—107 |
82 |