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Principia
Taxonomy
Principia was named by Brenckle (1982). It is not extant.
It was assigned to Archaeolithophyllaceae by Cozar and Vachard (2003).
It was assigned to Archaeolithophyllaceae by Cozar and Vachard (2003).
Synonymy list
| Year | Name and author |
|---|---|
| 1982 | Principia Brenckle |
| 2003 | Principia Cozar and Vachard |
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If no rank is listed, the taxon is considered an unranked clade in modern classifications. Ranks may be repeated or presented in the wrong order because authors working on different parts of the classification may disagree about how to rank taxa.
G. †Principia Brenckle 1982
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Diagnosis
| Reference | Diagnosis | |
|---|---|---|
| P. Cozar and D. Vachard 2003 | Branched, cylindrical to subcylindrical thallus, composed of a well-developed hypothallus consisting of polygonal to rounded cells. Perithallus very reduced to nearly absent, composed of small cells. In some species, cells of hypothallus may decrease slowly in size toward the perithallus. They are slightly elongate in longitudinal section, and they do no show an orientation (such as arched growth rows) or coaxial growth habits. Cell walls are dark and composed of microgranular calcite. Reproductive structures as conceptacles in the perithallus. |
Measurements
No measurements are available
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| Source: o = order | |||||
| Reference: Kiessling 2004 | |||||
Collections
No collection or age range data are available