A team of paleontologists has unearthed the world's oldest animal sperm aged 100 million years  frozen within a small crustacean in a globule of tree resin in Myanmar.

Previous Oldest Animal Sperm

According to the group of experts spearheaded by Wang He of the Chinese Academy of Science in Nanjing, the oldest known examples of fossilized animal sperm were earlier only 17 million years old.


The Chinese paleontologists were alongside their counterparts from Germany and Britain. The research discovery has been published in the "Proceedings of the Royal Society B: Biological Sciences."

The team also unearthed a fossilized sperm in the female ostracod, reported Times Now.

A Rare Opportunity

The researchers said that the data provide "an extremely rare opportunity" to study the progression of the reproductive process.


The sample was among one of many samples of Myanmar ostracods.

The unknown species of crustacean is a representation of modern-day mussel, an example of an ostracod, and has been named Myanmarcypris hui, reported Latestly.

The sperm cells have been described as large and originate from a mussel-like crustacean. The creature enclosing the reproductive cells has been dubbed a unique species and a special find for scientists interested in the evolution of sex.

The sperm is broadly dissemminated in oceans, swamps, lakes, ponds, and rivers. The ostracod sperm's weight is 0.676 gram and consists of 39 ostracod specimens.

The crustacean containing the world's oldest sperm is believed to have been an inhabitant of coastal and inland waters in modern-day Myanmar. It is surrounded by trees that produced resin.

Also Read: Sunscreen a Male Contraceptive? Fertility Study Links UV Ingredients To Impaired Sperm Function

The team of scientists evaluated 39 ostracods enclosed in a small piece of amber through 3D X-ray reconstruction.

Ostracods are tiny animals that date back an estimated 500 million years and could be found in freshwater lakes, oceans, and rivers.

Scientists assessed numerous ostracod specimens and evaluated their limbs and reproductive organs.

The ostracod discovered was a type of crustacean that has been in existence for 500 million years. It can be found in several oceans as of now, according to researchers in a paper published in the journal.

Discovered in a Female Specimen's Body

The experts stated that as they were discovered in a female specimen's body, she must have been fertilized shortly prior to being trapped in the tree resin.

The crustacean consists of "giant sperm cells in its reproductive tract" and is "the oldest fossil in which sperm cells have been conclusively identified," reported Science Daily.

The bodies of ostracods range in size from 0.2-30 mm and are protected by two calcareous valves which resemble a mussel shell.

According to the scientists, over one-third of the ancient ostracod sperm's body length bears a close similarity to its modern forms. The ancient ostracod could participate in sexual reproduction much like its present-day off-springs and could produce huge sperms.

The ripe world's oldest sperm was stowed in two receptacles inside the female ostracod awaiting for the maturity of eggs.

Related Article: Sperm Whale May Have Evolved a Forehead for Ramming in Combat