Pity the fisherman or sailor who staggers on deck in the morning and through bleary eyes sees a giant water spider, legs akimbo and buzzing ominously, coming at him.
No cause for alarm, however. It's just Proteus, a so-called Wave Adaptive Modular Vessel designed for everything from military uses to biological studies, ocean exploration and sea rescue.
The spindly catamaran is so efficient that it can travel 5,000 miles — farther than across the Atlantic — on one load of diesel fuel.
Daniel Basta, director of the National Marine Sanctuaries for the National Oceanographic and Atmospheric Administration, said the lightweight, low-cost and modular craft is well suited to scientific and environmental purposes using technology that is itself smaller and less cumbersome.
"Proteus will be able to launch and recover automatic vehicles, do remote vehicle operations, it will be tested for standard dive support operations, putting instruments on the bottom, collecting data — all the things that we currently do in one form or another, but most likely more cheaply, effectively and probably better."
Proteus was making its first appearance in New York, the fourth leg of a tour that began in San Francisco last January and will end in Washington, D.C.
It tooled around the harbor off lower Manhattan, a seagoing traffic-stopper that looked as if it might have escaped from Steven Spielberg's warehouse of props for the next "War of the Worlds" movie.
Although the U.S. Coast Guard had been alerted in advance to the strange craft's presence, it dispatched a small patrol craft to check it out.
Ugo Conti, an Italian-born engineer and oceanographer who designed Proteus, was aboard a chartered harbor cruise boat during his creation's star turn on Thursday.
Conti and his wife, Isabella, are the co-founders of Marine Advanced Research, Inc., a Silicon Valley-based firm that built the Proteus for about $1.5 million, she said.
The craft rides on metal and fabric pontoons that have hinges and shock absorbers to flex with the motion of the waves, which helps it to skim over the water at a maximum speed of 30 knots (34.5 mph).
Described as 100 feet long and 50 feet wide, the Proteus is no luxury craft. Its crew cabin, suspended like a gondola from its four-legged superstructure, is appropriately spartan for a boat named for a Greek sea god, who in mythology was able to change into different forms.
In keeping with that versatility, Proteus does have pleasure-boat potential. It can be fitted with different types of detachable cabins that can accommodate anything from a honeymooning couple to 12 passengers.