With paleo valentines! These gems (and their captions) are courtesy of Allie Weill — thank you Allie!! If you’re impressed, you get more Allie content on instagram (@al.m.weill) and the twitter (@Al_R_Wallace).
This valentine features Lepidodendron, a big fossil tree that could grow to 100 feet tall. Lepidodendron is classified in division Lycopodiophyta, the group that includes modern day club mosses and quillworts, one of the earliest branching off groups off vascular plants. Lycopods were much more diverse in the Carboniferous, when Lepidodendron lived, forming vast forests. The background of the valentine shows the distinctive leaf scars that covered the bark of these trees, while we see an illustration of what the full tree may have looked like in the foreground.
This valentine features a pith cast (infill of the center of the stem) of Calamites, a Carboniferous tree-sized relative of modern horsetails. Like the lycopods, the sphenopsids (horsetails and their relatives) were much more diverse historically than they are today, with sphenopsid trees common in Carboniferous forests.
This valentine features a close up of the structure and an illustration of Prototaxites, one of the most mysterious of fossils. It formed huge trunk-like structures and lived mostly in the Devonian period (~420-360 mya). Because of hyphae-like structures in the fossil, as well as isotopic evidence, it is widely considered to be an enormous fungus, perhaps even a lichen, but there are other theories.
This valentine features the stele (the primary vascular tissue and supporting pith) of an ancient fern called Ankyropteris, which lived in the Carboniferous period (~360-300 mya). During this time we get exceptional preservation of cellular structure in coal balls, a type of fossilization enabled by the coal swamps of the era. Many plants of this time can be identified by the unique shapes of their steles, and ferns have some strange ones, like this H-shaped stele.
