The Lepidurus


Lepidurus apus lubbocki

The paulis host, among other species, two archaic crustaceans: Lepidurus apus lubbocki Brauer and Triops cancriformis Schaff, which have remained unchanged for 200 million years.

In particular, the Lepidurus is a small crustacean that reaches the length of 12 millimeters, after molting 17 times. It is characterized by a large, shield-shaped carapace that protects its cylindrical and elongated body. It has two sessile eyes and a third naupliar eye. The genus Lepidurus has a well-developed plaque above the anus, an anatomical detail that differentiates this species from the Triops.

The female carries the eggs for a short period of time and then lays them on the bottom of the pond. The small eggs, with thick and strong shells, can withstand frost and drought and then hatch several years after being laid. They can withstand temperatures up to 80°C, pass through the digestive system of a frog without any harm, or even be carried by the wind for long distances.

An egg laid on the surface of a paùli hatches after one year. It usually lives on the bottom of pools of stagnant water, where it moves with its stomach facing down. It is omnivorous and digs in the mud, looking not only for plankton, but also larger prey, such as worms and midge larvae. Among these specimens, cannibalism is widespread, so they eat other smaller, weak, or dead Lepidurus. It is often at the top of the food chain inside the ephemeral ponds because it eats anything smaller than it.

 

Scientific classification

Domain

Eukaryota

Reign

Animalia

Phylum

Arthropoda

Subphylum

Crustacea

Class

Branchiopoda

Order

Notostraca G. O. Sars, 1867

Family

Triopsidae Keilhack, 1909

Genus

Lepidurus