Abstract Detail

Themes of land plant evolution, a celebration of the contributions of Leo J. Hickey

Hu, Shusheng [1], Taylor, David [2].

Paleoecology: An Albian flora from Jordan.

Abundant plant fossils were recovered from Albian fluvial and back-swamp sediments of the Jarash Formation (Kurnub Group) of Jordan. The flora is consists of angiosperm, ferns, and gymnosperms. Water lily Scutifolium jordanicum, marsilealean fern Marsileaceaephyllum mahisensis, and tree fern Weichselia reticulata are from a thin crevasse splay layer of a small fluvial system. Four species of other ferns, Phlebopteris sp., Piazopteris branneri, Aspidistes beckeri, and Cladophlebis sp. and three gymnosperms, Zamites hoheneggeri, Brachyphyllum sp.1, and B. sp.2 are from back-swamp dark, gray carbonaceous lens. Phlebopteris sp. represents a new fern species. Five pinnae preserved. Pinna rachis is up to 4mm wide. Pinnules are linear, apices obtuse, arising at an angle of 70º to 90º to the rachis, with thin midrib. Basal pinnules are about 2 mm wide and 10 mm long. Middle pinnules are 3 mm wide and 20 mm long. Lateral veins arise at an angle of 80º, dichotomous branching once, and forming polygonal meshes. Sori elliptic, 0.7 x 0.5 mm, arranged in a single row on each side of the midrib, with 7-8 sporangia, sporangium ca. 0.1 mm in diameter. Water lily S. jordanicum and marsilealean fern M. mahisensis may have grown along river or flood plain lake margin. However, tree fern W. reticulata is thought to have grown in tropical coastal areas. The co-occurrence of W. reticulata with S. jordanicum and M. mahisensis indicate that the habitats of water lily and marsilealean fern are not far from coastal areas. Also, M. mahisensis shows the existence of dry seasons because Marsileaceae needs a dry terrestrial phase for reproduction. This is consistent with climate implied from the xerophilic characters of W. reticulata. Matoniaceous fern Phlebopteris sp. and A. beckeri, as well as Z. hoheneggeri were probably growing in the back swamps, but P. branneri and Brachyphyllum spp. may have grown in dry upland close to the back swamps.

Broader Impacts:

1 - Yale University, Peabody Museum of Natural History, 170 Whitney Ave, New Haven, CT, 06517, USA
2 - INDIANA UNIVERSITY SOUTHEAST, Department of Biology, 4201 GRANT LINE ROAD, NEW ALBANY, IN, 47150, USA, 812-941-2377

Keywords:
paleoecology
Jordan
Albian
flora
Phlebopteris.

Presentation Type: Symposium or Colloquium Presentation
Session: C6
Location: Belle-Chasse/Riverside Hilton
Date: Tuesday, July 30th, 2013
Time: 2:15 PM
Number: C6003
Abstract ID:399
Candidate for Awards:None