Pararaucaria carrii

Name

Pararaucaria carrii

Rank

Species

Generic Name

[Genus] Pararaucaria

Authors (Pub.)

Stockey R. A. Rothwell G. W.  

Publication

Pararaucaria carrii sp. nov., anatomically preserved evidence for the conifer family Cheirolepidiaceae in the Northern Hemisphere [2013/3]

Journal

International Journal of Plant Sciences

Volume

174

Issue

3

Page number

447

Year

2013

Fossil Status

cones (ovuliferous)

Stratigraphy

Callovian

Strat. comment

Officer Member, Trowbridge Formation

Location

roadside exposure along the Paulina-Suplee Highway, 5 mi east of Izee (SE 1/4 sec. 13; T. 17 S, R. 28 E, Grant County, Oregon, USA

Paleoregion

America (North)

Data for Holotypus

Repository

University of Oregon, Museum of Natural and Cultural History, Eugene, USA

Repository Number

F-55431: P1 H bottom (bot) and P1 I1 top, plus peels, and slides prepared from that specimen

Num

2-6

Pub.

Pararaucaria carrii sp. nov., anatomically preserved evidence for the conifer family Cheirolepidiaceae in the Northern Hemisphere [2013/3]

Diagnosis

Cylindrical seed cones at least 2.8 cm long, 1.3 cm wide. Cone axis with helically arranged bract/scale complexes consisting of large ovuliferous scale, subtended by broad, flattened bract; bract and scale separating near base. Scale trace flanked by two frequently connected triangular sclerenchyma bundles within cone axis and basal region of ovuliferous scale. Tissue toward apex of ovuliferous scale forming seed-enclosing pocket. Adaxial pocket forming tissue thickening distally, thinning toward scale base, terminating near seed micropyle; open toward cone axis. Bract/scale trace diverging from stele as single cylindrical unit enclosing parenchyma but separated from each other by one or two layers of parenchyma cells. Traces separate rapidly to reveal crescent-shaped bract trace and band-shaped scale trace in cortex of cone axis. Bract trace dividing to form several branching bundles accompanied by transfusion tissue distally. Scale trace extending distally as single bundle, dividing distal to seed; vertical division producing small seed bundle, bending back to vascularize seed, and large scale bundle branching repeatedly. One seed per scale, 5.3 mm long, widest at midregion, ;6.5 mm wide. Integument with outer epidermis of isodiametric cells with dark contents, one or two palisade layers, rarely shrunken into I-beam shapes, and several inner layers of randomly arranged cells. Nucellus adnate to integument up to level of parenchymatous apical region. Seed vascularized at base by cup-shaped zone of tracheids located within nucellar tissue.