Locality

Ammam Lagoon Locality 1

 

Description

From Moiseeva (2012) (p. 43)

"One specimen available in collection represents an upper fragment 5 cm long of sterile
bipinnate frond. Linear lanceolate terminal pinnae are up to 1.5 cm long and about 0.8 cm wide near their base. The pinnae arrangement relative to the first order rachis about 1 mm thick is subopposite or almost opposite with intervening intervals up 0.7 cm, and pinnae partially overlap each other.

Sphenopteroid pinnules of ovate lanceolate outlines with narrowing base extend decurrently to the frond rachis. The largest of them up to 7 mm long and 3 mm wide depart from rachis at the angles of 40° to 50°. Pinnule margins are variably dissected. Larger well developed pinnules have 2–3 upper and 1–2 lower lobes acute at the ends. In apical part of frond and terminal pinnae, pinnules with serrate margins are of lesser dimensions. Dissection is developed only within the upper half (or third) of pinnules, which are entire margined below.

Venation in pinnules is imperfectly pinnate. Midribs departing from the pinna axis dichotomize several times, and every new vein almost as thick as the midrib enters the pertinent lobe (denticle)."

 

Remarks

From Moiseeva (2012) (p. 43)

"Holotype: specimen figured by Kryshtofovich (1958a, pl. I, fig. 1) from the Rarytkin Formation of the Pekulney Range, the Pekulneyveem River, exposure 25."