Table of Contents U.S. SECURITIES AND EXCHANGE COMMISSION Washington, DC 20549 FORM 10-Q [X] QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2019 [ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to . Commission File No. 000-26719 MERCANTILE BANK CORPORATION (Exact name of registrant as specified in its charter) (State or other jurisdiction of (IRS Employ ...