Isla Holbox, Mexico — Separated from the Yucatan Peninsula by a lagoon, this pristine island has streets of sand, iguanas that roam among humans, and a police presence best described as casual. In its quaint town, golf carts are the primary mode of transportation.

"It's like out of movie, isn't it?" said a chuckling Ramon Chan, a 41-year-old vendor who on a recent day was hacking away at fresh coconuts from a cart on the beach.

In recent years, however, Isla Holbox (pronounced "holl-bosch") has sat at the center of a complex legal dispute pitting powerful developers seeking to build a high-end resort against a group of longtime residents who say they were cheated out of their rights as holders of revolutionary-era communal lands, known as ejidos.

The fight illuminates the growing practice of transferring communal ejidos — which make up slightly more than half of the national territory — to private hands, a practice that was authorized in 1992 but remains a legal twilight zone.

In separate cases, nine islanders allege that Peninsula Maya Developments offered to buy their individualized ejido parcels in a 2008 deal to which they agreed. But in the process, the ejidatarios allege, the developers also persuaded them to unwittingly sell their permanent, constitutionally guarded titles to the Holbox ejido at large.

Because Mexico's agrarian law refers to "inalienable" titles to ejidos, the islanders are asking courts to nullify the dual sale of their parcels and titles.

In response, the company said the sales were legal and clear and suggested in a statement that the ejidatarios are trying to shake them down for more money than the original price of about $388,000 USD.

The developers contend that the ejidatarios are challenging the deal through loopholes in the ejido laws, which established strict codes meant to protect the rural peasant class from abuse by private interests. The suits over the $3.2 billion development plan are working their way through Mexico's agrarian tribunals, with one awaiting a hearing before the Supreme Court.

In the meantime, the island simmers with discord, and the eastern end, where La Ensenada resort would be built, remains untouched.

Roman Avila, a 60-year-old former fisherman and Holbox ejidatario, said operators working for the development wooed islanders with gifts and promises of fortunes for all if they signed over their ejido titles to the Trust for the Promotion and Sustainable Development of Isla Holbox, which the developers set up.

They also told the ejidatarios, he said, that they would ensure any project they constructed would be environmentally sound, a welcome message after Isla Holbox suffered heavy damage in the hurricane season of 2005.

The islanders didn't know precisely what they were signing, he said.

"Look, this is not an excuse, but when Hurricane Wilma hit here, we were left with no money, and these people came who wanted our lands, and, well, they offered us money," Avila said. "And we naively fell."

The problem, developers complain, is that whenever an ejidatario feels like invoking his or her constitutionally mandated rights, no matter what a contract might say, he or she can challenge a deal.

Fernando Ponce, lead investor in the Holbox development plan and chief of the Coca-Cola distribution company Bepensa, declined requests for an interview.

The Peninsula Maya Developments company said the price received by the islanders was fair given anticipated development costs. The statement did not directly address the ejidatarios' allegations that they had been tricked into ceding their titles, but hinted that the plaintiffs want it both ways — suing to regain their titles while keeping the original payment.

The Supreme Court docket on the Holbox case blocks out the names of the ejidatarios suing to stop the resort plan. In the meantime, 65 ejidatarios' names are officially replaced by those of new owners on the current paperwork of the agrarian bureaucracy. Many of the new names have been identified in press reports in Mexico as relatives and business and political associates of Ponce.

Avila says the developers used confusing paperwork to trick them into signing off on the rest of the un-parceled communal lands on the island. In court, the ejidatarios also contend that the parcels were not properly appraised and that they were grossly underpaid for them, perhaps as low as 5 percent of their market value, which would also make the sale void.

Mexico's environmental and natural resources ministry, Semarnat, is reviewing the proposal for La Ensenada. The 463 page development plan calls for three hotels with up to 195 rooms, and as many as 872 residential units, including villas and condominiums.

The tiny town on the island, which is in a federally protected natural reserve, has 18 small hotels with a capacity for 1,200 guests, said Alejandro Cañedo, a member of the island's hotel-owners business group. The plan calls for total use of 10 percent of the 2,422 acres acquired through the sale of ejido parcels to the private trust tied to Peninsula Maya Developments.

The rest of the acquired land would remain undeveloped tropical forest and coastline, where hundreds of species, such as whale sharks, flamingos, and other wildlife find refuge, the developer says.

Prospero Espinosa, a lawyer at the Cancun office of the Mexican Environmental Law Center, said that even 10 percent would have a negative effect. Plus, Espinosa said, the project could be modified later if it is greenlighted, opening the possibility of additional growth and damages.

"More people would also come to the island, and the island would become more saturated," Espinosa said.

David Culberson, an experienced eco-tourism developer in the Caribbean region who also owns a property on the western end of Isla Holbox, is a consultant on the project. He said the plan for La Ensenada would avoid the kind of unplanned growth that has defined the island's town.

"I've spent my entire adult life trying to prove that nature and man need to live together," Culberson said. "I know that's what the project is striving to do. Many places are overdeveloped because usually there's not a single owner or a single division."

Maria Alberta Pech Che, 69, is a widow of an Isla Holbox ejidatario. She said she is concerned that "the peace and the tranquillity" of the island community will be disrupted if La Ensenada is built.

"I've been to Cancun and to Playa del Carmen, and it makes me very sad to see what it has become, with so many hotels, cars, and places where people go to drink and dance - with no respect for nature," Pech said. "I pray to God that this place preserves its charm."

On a recent weekend night on the island, the small central plaza of Holbox's town was teeming with tourists, vendors sporting dreadlocks, and islanders playing pickup basketball on a paved courtyard. Many residents, including relative newcomers, said the vibe on Holbox is already changing faster than they can keep up with.

"It's exploding," said painter Rigel Suari, a native of Merida who operates a cultural center and gallery on the plaza. "Everyone is claiming their space, their spot, and I don't think that's going to stop."