Araucaria famii Stockey et Rothwell

Plant Fossil Names Registry Number: PFN002736

Act LSID: urn:lsid:plantfossilnames.org:act:2736

Authors: R. A. Stockey & G. W. Rothwell

Rank: species

Genus:

Reference: Stockey, R. A. & Rothwell, G. W. (2020): Diversification of crown group Araucaria: the role of Araucaria famii sp. nov. in the mid-Cretaceous (Campanian) radiation of Araucariaceae in the Northern Hemisphere. – American Journal of Botany 107(online)(7): 1072–1093.

Page of description: 1073

Illustrations or figures: figs 1–62

Types

Original diagnosis/description

Seed cone, spherical; 6 cm in diameter. Bract/scale complexes numerous, helical, composed of large, winged bract and small ovuliferous scale, both with upturned tips; some bract tips recurved. Bract base thick, bulging; wings wide, papery thin. Cone peduncle bearing rhomboidal fleshy leaves with scattered sclereids and sclereid clusters in parenchymatous ground tissue. Compartmented cells in mesophyll. Stomata sunken with deep substomatal chambers, cuticle surface smooth, Florin rings absent. Abaxial stomata alternate with hypodermal bands of sclerenchyma fibers. Stomata with 4–5 subsidiary cells, most oriented obliquely to long axis of leaf. Pith of peduncle and cone axis parenchymatous with scattered sclereids, some stellate, and resin canals. Cone axis vasculature nearly complete cylinder at cone base, dividing into numerous bundles in cone. Vascular system to bract/scale complex a single strand dividing to form numerous vascular bundles in bract separated by transfusion tissue. Resin canals in bract/scale complex numerous, branching. Ovuliferous scale separating from bract near seed chalaza, parenchymatous with sclereid clusters, bearing numerous stomata with prominent polar extensions on guard cells. Seeds ovoid, 1.2 cm long, 1.2 cm in diameter, vascularized at chalaza by two or three bundles that branch in sclerotesta dividing to form numerous bundles in endotesta near seed chalaza; micropyle mouth-shaped. Sclerotesta thick, sclereids branched, interlocking. Endotesta cells thinwalled, elongate. Nucellus free from integument, except at base; apex highly convoluted. Megagametophyte cells small, with granular contents. Embryos spathulate, cotyledons shorter than hypocotyl.

Etymology

The species is named for John and Patrick Fam of Coquitlam, British Columbia who generously provided the specimen for scientific study.

Stratigraphy

Cretaceous, Upper Cretaceous, Campanian
sediments from which concretions are derived are part of the Haslam Formation of the Nanaimo Basin, dated as early Campanian

Locality

Canada
West of Brannen Lake at Moto-X Pit; 3 km west of Nanaimo (49°12′16″N, 124°06′01″W; UTM 10U DK 198495) on Vancouver Island, British Columbia