Locality

Amaam Lagoon (probably Locality 1)

 

Description

From Moiseeva (2012) (p. 47)

"Leafy shoots commonly with axis diameter as thick as 1.0–1.5 mm and opposite arrangement of vegetative branchlets; there are long perennial and shorter deciduous annual shoots. In short shoots, linear distichous-opposite leaves with distinct midribs are 3–4 to 15–17 mm long and 1.5– 2.5 mm wide. Somewhat widened leaf base narrows abruptly and grades into short petiole producing oblique to subparallel decurrent scars of the petiole attachment. The leaf apex usually obtuse-rounded is sometimes acuminate, bearing terminal spinule. Short shoots are so thickly leaved that leaves come in contact with each other. Orientation angles of leaves relative to the shoot axis change from 45° to 80°–90°.

In the longest shoots available in collection, which are perennial most likely, the opposite leaf arrangement is disturbed. Alternate to nearly opposite leaves of these shoots are larger and can be as long as 2.0–3.5 cm. In the other morphological traits, they do not differ from leaves of shorter shoots."

 

Remarks

From Moiseeva (2012) (p. 47)

"Lectotype: specimen figured by Newberry (1898, pl. XXVI, fig. 2) from the Paleocene deposits in Montana, North America."