efe-epaLimpio, Paraguay

Thousands of tourists have flocked in recent days to this small town outside Paraguay's capital, where giant lily pads (floating leafs of the Victoria cruziana, a water lily species) have returned and are blanketing the surface of a lagoon.

Lily pads of such massive size, some of up to two meters (6.5 feet) in diameter, are only seen in that lagoon near the Paraguay River once every three or four years, local residents say.

In response to the surge of visitors, area fishermen are leaving aside their rods and nets and charging tourists 10,000 guaranies ($1.70) for a boat ride through the lily-filled lagoon.

The Victoria cruziana is known locally as the Yacare Yrupe (caiman's basket in the Guarani language) because its lily pads have a rough texture similar to a crocodile's skin.

The pads appear to float on top of the water, but they are in fact supported by a spiny stem that extends to the bottom of the lagoon.

The leaves and their thick rims nearly touch one another and form a green blanket that almost completely cover the surface of the water.

It is popularly believed that this species of water lily has medicinal properties that can cure asthma and other respiratory problems if it is dried and soaked in water to make an infusion, Pablo Lucerna, a 44-year-old local fisherman who is among those organizing tourist excursions, told EFE.

"If you take it out now, you have to put it in the sun for like two days. Later you put (the piece of leaf) in boiling or normal water. For mate (an infusion), it's boiling water," he said.

Lucerna said his mother used to prepare that infusion for him when he was young as a remedy for a respiratory ailment.

Because of those perceived medicinal qualities, some of the lily pads were cut and destroyed last weekend when an initial batch of visitors arrived last weekend at the lagoon, located in Limpio's Piquete Cue neighborhood.

Some people even stuffed entire lily pads into cars and trucks and drove off with them.

In response, a group of naval officers were deployed to the lagoon to protect that fragile ecosystem and ensure these aquatic plants stay alive for at least one or two months before withering.