Researchers used a type of holotomography to capture 3-D images of this 100 million-year-old fossil ostracod called Harbinia micropapillosa. The left arrow shows the preserved inner part of the esophagus, while the right arrow points to the two seminal receptacles, where this female stored the giant sperm cells after mating. Credit: Renate Matzke-Karasz
From Live Science:
The fossilized remains of a tiny 100 million-year-old crustacean reveal evidence of what to her at least would have been giant sperm, measuring perhaps as long as her body.
While the sperm itself was not preserved, 3-D images of the female's specialized receptacles indicate she had just finished having sex and that they were filled with sperm that has since degraded. (The oldest direct evidence of sperm comes from a springtail living some 40 million years ago, according to the researchers.)
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