Cymastrobus irvingii

Name

Cymastrobus irvingii

Rank

Species

Generic Name

[Genus] Cymastrobus

Authors (Pub.)

Evreïnoff M. Meyer-Berthaud B. Decombeix A.-L. Lebrun R. Steemans P. Tafforeau P.  

Publication

A new Late Devonian isoetalean lycopsid from New South Wales, Australia: Cymastrobus irvingii gen. et sp. nov. [2017/9]

Journal

Palaeontologia Electronica

Volume

20

Issue

3.47A

Page number

3

Year

2017

Fossil Status

cones

Stratigraphy

Famennian

Location

left bank of the Manilla River, upstream from the Connors Creek crossing, Mandowa Mudstone, Barraba, New England, New South Wales, Australia

Paleoregion

Gondwana (Australia)

Data for Holotypus

Repository

National Museum of Victoria, Melbourne, Australia

Repository Number

NMVP 161998

Num

1-5

Pub.

A new Late Devonian isoetalean lycopsid from New South Wales, Australia: Cymastrobus irvingii gen. et sp. nov. [2017/9]

Diagnosis

Large bisporangiate cone that may exceed 8 cm long and 5 cm wide. Cone axis narrow, about 10% the width of the cone, containing a ring of primary xylem showing a corrugated outline with an almost continuous band of exarch protoxylem; sporophyll traces departing from the bays of the primary xylem cylinder. Sporophyll-sporangium units arranged helically, about 8-10 per gyre. Sporophylls comprised of a long, narrow pedicel widening distally but without alations, and a delicate distal lamina oriented perpendicularly to the pedicel; pedicels showing an abaxial keel and a distal heel, the latter forming hexagonal shields protecting the sporangia externally. Megasporangia and microsporangia in distinct parts of the cones; megasporangia proximal, enclosing a large number of megaspores. Casts of megaspore central body up to 500 μm in diameter, showing numerous small circular pores arranged in several rows around the trilete mark, smooth elsewhere. Casts of microspore central body less than 100 μm in diameter, showing one small pore between the rays of the trilete mark.