This insect flew into my house in Singapore while it was raining. Size is around 1.5 inches. What is this?
This is a beetle Coleoptera, possibly from the family of the 'ground beetles' Carabidae
As this family is one of the most speciose animal families, pinpointing an exact species will be difficult, especially in the tropics. I think your specimen belongs to the genus of Carabus, they look similar as you can see on the picture from wikipedia commons below:
- Long legs.
- Often a distinct pattern of dots and stripes on the shields.
- Long antenna with many segments
EDIT: As @theforestecologist pointed out, the body shape more resembles the family of Meloidae. Most Meloidae don't have dots on the shield, but for example lytta does. https://bg.m.wikipedia.org/wiki/Файл:Lytta_aenea.JPG