| 1. |
Ultimate
branching alternate |
D.
dentata
|
| 1. |
Ultimate
branching dichotomous or cervicorn, but sometimes also proliferous |
2
|
| 2. |
Thallus
margin aculeate-dentate |
D.
ciliolata
|
| 2. |
Thallus
margin shallowly erose-dentate |
D.
jamaicensis
|
| 2. |
Thallus
margin entire |
3
|
| 3. |
Branching
essentially dichotomous throughout, but the division sometimes
a little unequal in size |
4
|
| 3. |
Branching
ultimately cervicorn to irregular, though whan plant is young
almost completely dichotomous |
D.
cervicornis
|
| 4. |
Branches
regualrly spirally twisted, sinuses broad, wide-angled |
D.
volubilis
|
| 4. |
Branches
not consistently twisted |
5
|
| 5. |
Branches
to 1-2 mm broad or more below, but ultimately filliform at least
above, aften with an abrupt transition; sinuses wide-angled |
D.
divaricata
|
| 5. |
Banches
of nearly uniform width throughout, about 0.5 - 1.0 mm broad or
rarely more; branch sinuses narrow |
D.
linearis
|
| 5. |
Branches
broader, not narrowed above |
6
|
| 6. |
Internodal
segments less than 4 breadth long; upper sinuses broad, with as
angle of about 80 |
|
| 6. |
Internodes
longer; upper sinuses usually narrower |
7
|
| 7. |
Internodes
5-10 breadths long |
|
| 7. |
Internodes
15-20 breadths long |
D.
indiaca
|
