"Long before it's in the papers"
January 27, 2015


In dinosaur era, fleas were giant too

March 1, 2012
Courtesy of Nature
and World Science staff

A new re­port de­tails the dis­cov­ery of what sci­en­tists call the most an­cient known fleas—in­sects up to 20.6 mm (0.8 inches) long.

The crea­tures would have been rough­ly con­tem­po­ra­neous with some well-known di­no­saurs such as the spiky Steg­o­saur­us and the enor­mous, long-necked Ap­at­o­saurus (form­er­ly known as Bron­to­sau­rus) and its kin.

The prim­i­tive pests came from the Mid­dle Ju­ras­sic and Ear­ly Cre­ta­ceous per­iods, and had­n’t yet evolved hind legs ca­pa­ble of jump­ing, ac­cord­ing to the re­search­ers. The re­port, by An­dré Nel of the Na­t­ional Mu­se­um of Nat­u­ral His­to­ry in Par­is and col­leagues, ap­pears in the March 1 is­sue of the re­search jour­nal Na­ture.

Fos­sils of the crea­tures, found in Chi­na, show they boasted body lengths of 14–20.6 mm in fe­males and 8–14.7 mm in males, and were wing­less like mod­ern fleas, Nel and col­leagues said. The in­sects are de­scribed as hav­ing many de­fin­ing fea­tures of fleas while re­tain­ing some prim­i­tive traits. 

Their most im­pres­sive fea­ture, how­ev­er, was their long, saw-toothed blood­suck­ing tube, called a suc­to­ri­al siphon—used for pierc­ing the hinds of their hosts and which was long­er in fe­males than in males, ac­cord­ing to the re­search­ers.

The struc­ture of the an­cient fleas sug­gests they fed on rep­tiles pri­mar­i­ly, be­fore mov­ing on to mam­mals and birds lat­er on, the re­port says.

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A new report details the discovery of what scientists call the most ancient known fleas—insects up to 20.6 mm (0.8 inches) long. The creatures would have been rough ly contemporaneous with some well-known dinosaurs such as the spiky Stegosaurus and the enormous, long-necked Apatosaurus (former ly known as Brontosaurus) and its kin. The primitive pests came from the Middle Jurassic and Ear ly Cretaceous eras, and hadn’t yet evolved hind legs capable of jumping, according to the researchers. Their report, by André Nel of the N ational Museum of Natural History in Paris and colleagues, appears in the March 1 issue of the research journal Nature. Fossils of the creatures, found in China, show they boasted body lengths of 14–20.6 mm in females and 8–14.7 mm in males, and were wingless like modern fleas, Nel and colleagues said. The insects also had many defining features of fleas while retaining some primitive traits. Their most impressive feature, however, was their long, saw-toothed bloodsucking tube, called a suctorial siphon—used for piercing the hinds of their hosts and which was longer in females than in males, according to the researchers. The structure of the ancient fleas suggests they fed on reptiles primarily, before moving on to mammals and birds later on, the report said. n