Emwadea

Name

Emwadea

Rank

Genus

Authors (Pub.)

Dettmann M. E. Clifford H. T. Peters M.  

Publication

Emwadea microcarpa gen. et sp. nov.—anatomically preserved araucarian seed cones from the Winton Formation (late Albian), western Queensland, Australia [2012/3]

Journal

Alcheringa

Annee/Jahrgang

2012

Volume

36

Issue

10.1080/03115518.2012.622155

Page number

7

Year

2012

Parent Taxon

[Family] Araucariaceae

Fossil Status

cones

Type

Emwadea microcarpa

Diagnosis

Ovulate cone with spirally arranged cone-scale complexes emanating from a central vascularized axis. Vascular supply from axis to cone scale-complexes single at origin; branching within bract scales with one branch supplying a stalked, inverted ovule, and the other(s) extending towards the distal end of bract. Ovule with lateral wings, which are formed from integument, and with a sclerotic chalaza, which is extended distally to form a vascularized outgrowth contiguous with lateral wings; ovule and associated chalazal extension (‘ligule’ sensu Farjon 2010) free from bract scale except at vascularized stalk; the stalk (and the vascular branch leading to it) comprising the ovuliferous scale. Integument three-layered. Nucellus free from integument except at chalaza where it is fused to the integumentary layer; cellular structure not preserved. Seeds bisymmetrical, winged; embryo with two cotyledons. Peduncle leaves imbricate, spirally arranged; with spreading and incurved bifacial blades and acute tips. Leaf surface ridged; longitudinally aligned stomata occur in rows and are confined to adaxial surface; epidermal cells between stomatal rows elongate, the long axis parallel to leaf axis.