A tiny butterfly hovering at his feet caught Jim Snyder's eye as he crossed a vacant lot near the Waikiki Library.

He got down on his hands and knees, and his heart stood still when he saw the flash of blue on its wings.

“;I recognized it right away. I knew it was something different,”; said Snyder, who discovered in March a new butterfly that has made a home in Hawaii. “;It was such an exciting find.”;

The butterfly, commonly known as the lesser grass blue, has never been seen in the islands or the United States, and its migration here is “;pretty remarkable,”; said Daniel Rubinoff, an associate professor in the College of Tropical Agriculture and Human Resources at the University of Hawaii at Manoa.

He described the Zizina otis as a beautiful and frail member of the gossamer wing family, usually found in Southeast Asia and the Pacific, and some parts of Africa. Rubinoff took part in the investigation and identification process. With Snyder's discovery, there are 17 butterfly species in Hawaii, Rubinoff added.

Snyder, a Hawaiian Cement controller who has photographed about 1,000 species of butterflies in the U.S., Canada and Mexico, was able to spot the unique characteristics of a butterfly no bigger than three-eighths of an inch long.

“;I've trained my eyes to be so observant that I see things others don't see - you see amazing things out there,”; said Snyder, who grew up catching and collecting butterflies in San Diego.

The butterfly is distinguished by the iridescent blue on the top side of its wings; the underside is brown. Its eyes are grayish-brown instead of the “;jet black eyes”; that other blue species in Hawaii have.

Snyder also saw how closely it flew to the ground: “;No other butterfly behaves like that.”;

“;It turned out that it was part of a mating pair, which was a stroke of luck because then they fly much slower than usual.”;

Another bit of luck was that he had his camera with him, and he followed the two butterflies for several minutes until they flew away. The female was laying eggs on the host plant, the Mimosa pudica, nicknamed “;sleeping grass”; because its leaves fold up when touched.

He went back the next day with binoculars and a magnifying glass and found 20 or 30 more over two hours at the site on Kapahulu Avenue near the Ala Wai Golf Course.

“;I wanted to make sure it wasn't a chance find. ... There are so few butterflies in Hawaii that an opportunity to find a new one is rare. Usually there are strays from across the border and you find only one, but this is an established colony,”; said Snyder, adding that he has also seen them near Pearl Harbor.

Rubinoff said the new butterfly does not seem to be harmful to the local environment, but “;we need everybody's help ... as an early warning system”; to detect invasive species. He appreciated Snyder's trained eyes and skills, which showed that “;not all (scientific discoveries) happen in an ivory tower.”;