Amersinia obtrullata Manchester, P.R.Crane et Golovn.

Plant Fossil Names Registry Number: PFN001763


Authors: S. R. Manchester, P. R. Crane & L. B. Golovneva

Rank: species

Genus: Amersinia Manchester, P.R.Crane et Golovn.

Reference: Manchester, S. R., Crane, P. R. & Golovneva, L. B. (1999): An extinct genus with affinities to extant Davidia and Camptotheca (Cornales) from the Paleocene of North America and Eastern Asia. – International Journal of Plant Sciences 160(1): 188–207., link

Page of description: 190

Illustrations or figures: figs 2–5

Name is type for

Amersinia Manchester, P.R.Crane et Golovn. 1999


Holotype UF 5976, Paleobotany Collections, Florida Museum of Natural History, Gainesville, Florida, USA
Figures: fig. 3.20
Previously published illustration or figures: fig. 24G in Crane, P. R., Manchester, S. R. & Dilcher, D. L. (1990): A preliminary survey of fossil leaves and well-preserved reproductive structures from the Sentinel Butte Formation (Paleocene) near Almont, North Dakota. – Fieldiana Geology 20: 59.

Note: Paratypes: PP 34462, 34467, 34469, 34487, 44586; UF 5975, 5976 (Almont, North Dakota; UF locality 15722); S 8057, 8066, 8084, 8090–8093, 8097, 8100, 24203, 48931 (Joffre Bridge, Alberta; UF locality 15763); UF 25272 (East Fork Razor Creek, Montana; UF locality 18163); UF 14048, 14062, 14120, 14121, 25163, 25164, 25167, 25755 (Big Flat Draw, Wyoming; UF locality 15778); UF 14317 (Black Buttes, Wyoming; UF locality 15886); USNM 497406 (Foster Gulch, Montana; USNM locality 14163); USNM 498839, 498840 (Makton Coal Mine, Montana; USGS 8885).

Original diagnosis/description

Infructescence as described in generic diagnosis; heads ca. 12–25 mm (mature heads 21–25 mm) diameter, peduncle 9–13 mm long. Head consisting of a globose to ellipsoidal receptacle 6–12 mm diameter bearing up to ca. 40 fruits. Fruits three (rarely four) loculed, obtrullate in longitudinal outline, rounded triangular (rarely quadrangular) in transverse outline, 6.5–12 mm long, 4–7 mm wide, length/width ratio 1.6–2. Base truncate, apex obtuse, but at the extreme apex flared into a weakly developed collar (fused epigynous perianth) with a pulvinate disk from which three divergent style arms arise. One seed per locule, elongate with a ventral raphe. Dorsal germination valve formed in the apical one-fourth of each carpel.


The epithet obtrullata refers to the shape of the fruits.


Paleogene, Paleocene


United States
Almont, North Dakota.

Plant fossil remain

macro- and meso-fossils-embryophytes except wood


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