Aug 19 (Reuters) - Lyntris' shares fell 11.4% in the defense contractor's New ‌York debut on Wednesday, giving ‌the company a valuation of $1.78 billion and underscoring ​investor caution toward new listings.

Shares of the company opened at $15.5 each, below the initial public offering price of $17.50 apiece.

The ‌Falls Church, Virginia-based ⁠company and some of its existing shareholders downsized the IPO ⁠to 17 million shares on Tuesday and raised $297.5 million, after the company and ​its shareholders ​had initially ​marketed 24 million shares ‌at $19 to $22 apiece.

The company sold about 5.7 million shares in the IPO, more than its earlier proposal of about 4.9 million shares, while existing shareholders ‌cut their offering by ​more than 7.8 million ​shares.

The U.S. ​IPO market has rebounded strongly ‌in recent months, bringing ​startups across ​sectors to the public markets. However, investors remain selective.

Investor caution has forced ​several ‌companies to trim their deal sizes.

(Reporting ​by Pritam Biswas in Bengaluru; Editing ​by Tasim Zahid)