AA 2230 then UA 2190 at Houston
Miami → Houston → Las Vegas
Timetable, Houston time
23:58AA 2230 from Miami at the gate
17:00UA 2190 to Las Vegas leaves the gate
17 h 02 apart on the timetable, overnight
UA 2190 leaves 17 h 02 after AA 2230 arrives on the timetable: more than half a day, so not a connection we count.