Abstract Detail

Paleobotany

Stockey, Ruth A [1], Mindell, Randal A. [2].

Permineralized Sloanea (Elaeocarpaceae) from the Eocene of North America.

A seed bearing, valvate capsule of Sloanea (Elaeocarpaceae) has been recovered from the Middle Eocene Appian Way locality, on Vancouver Island south of Campbell River, in British Columbia, Canada. The fruit is nearly quadrangular in cross section, 2.1 cm in diameter, with four carpels, each containing one or more seeds. The outer fruit wall is 2 mm thick from which emerge elongate spines that are circular in cross section and at least 1.5 mm long in places where the fruit is less abraded. The inner fruit wall is composed of narrow, transversely, elongated cells, that are circum-locular in cross section. The carpels are separated by a thin, four-armed, parenchymatous central axis. Carpels open by loculicidal dehiscence. Seeds are circular in cross section with an integument containing a thick-walled palisade of densely pitted sclerenchyma, underlain by a zone of more isodiametric sclereids. The seed is surrounded by an external layer of very thin-walled cells, 4-5 cells thick, that may represent an aril. A zone of copious, cellular endosperm surrounds the embryo which is mostly infiltrated with pyrite and not well preserved. Fungal hyphae and sclerotia are common in some of the fruit tissues. This fruit is the first reported permineralized fruit of Sloanea from North America, a genus that until recently was thought to have originated in the Southern Hemisphere tropics. The possible aril suggests the presence of modern dispersal systems for Sloanea by the Middle Eocene. This fossil provides additional evidence for the hypothesis that Elaeocarpaceae may have originated in the Northern Hemisphere.

1 - Oregon State University, Botany and Plant Pathology, 2082 Cordley Hall , Corvallis, OR, 97331, USA
2 - Douglas College, Earth and Environmental Sciences, 700 Royal Avenue, New Westminster, BC, V3M 5Z5, Canada

Keywords:
Elaeocarpaceae
Sloanea
Eocene
Fruits
fossil.

Presentation Type: Oral Paper
Session: 28, Mesozoic to Pleistocene Paleobotany
Location: 102/Savannah International Trade and Convention Center
Date: Tuesday, August 2nd, 2016
Time: 2:30 PM
Number: 28005
Abstract ID:439
Candidate for Awards:None