Sagenopteris

Sagenopteris is a genus of extinct seed ferns from the Triassic to late Early Cretaceous.[1][2]

Sagenopteris
Temporal range: Triassic-Early Cretaceous
~242–105 Ma
Sagenopteris phillipsii leaves, Middle Jurassic, Gristhorpe Bed, Cloughton Formation, Cayton Bay, Yorkshire.
Scientific classification
Kingdom: Plantae
Clade: Tracheophytes
Division: †Pteridospermatophyta
Order: †Caytoniales
Family: †Caytoniaceae
Genus: †Sagenopteris
Presl 1838
Species

See text

Description

Sagenopteris has palmately arranged leaves with anastomosing venation.

Different organs attributed to the same original plant can be reconstructed from co-occurrence at the same locality and from similarities in the stomatal apparatus and other anatomical peculiarities of fossilized cuticles.

Species

The following species have been described:[1]

Distribution

Fossils of Sagenopteris have been registered in:[1]

Triassic

Argentina, China, Germany, Greenland, Italy, Japan, Kyrgyzstan, the Russian Federation, Sweden, Tajikistan, Ukraine, United States (Virginia, Virginia/North Carolina).

Jurassic (to Cretaceous)

Afghanistan, Antarctica, Argentina, Azerbaijan, Belarus, Canada (British Columbia, Yukon), China, Colombia (Valle Alto Formation, Caldas), Georgia, Germany, Greenland, India, Iran, Italy, Japan, Kazakhstan, Kyrgyzstan, Mexico, Peru, Poland, Romania, the Russian Federation, Tajikistan, Turkmenistan, Ukraine, the United Kingdom, United States (Alaska, Montana, Oregon/Idaho), and Uzbekistan.

Cretaceous

Belgium, Canada (British Columbia), Greenland, the Russian Federation, and the United States (Montana).

gollark: Huh. There are probably a lot of weird physical-world quirks like that then.
gollark: Grocery store automation might actually be a really hard case, since - as well as packages being non-rigid and in weird shapes/sizes - current grocery store designs involve customers physically interacting with products and moving them around and such.
gollark: You could just operate on a bounding box containing the entire thing, if you have a way to get that from images.
gollark: I'm not sure this is true. It should still be more efficient to have a *few* humans "preprocess" things for robotics of some kind than to have it entirely done by humans.
gollark: Those are computationally hard problems, but I would be really surprised if there wasn't *some* fast heuristic way to do them.

References
  1. Sagenopteris at Fossilworks.org
  2. Elgorriaga, A.; Escapa, I. H.; Cúneo, R. (2019). "Southern Hemisphere Caytoniales: vegetative and reproductive remains from the Lonco Trapial Formation (Lower Jurassic), Patagonia". Journal of Systematic Palaeontology. doi:10.1080/14772019.2018.1535456.
  3. Retallack, G.J. & Dilcher, D.L. (1988). "Reconstructions of selected seed ferns". Missouri Botanical Garden Annals. 75: 1010–1057.
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