Check out The Creative Cafe (take a long time to accept new writers) and The Junction.
PS I Love You also do a Fiction Friday but not always easy to get into as a bigger pub. Genius in a Bottle is a new pub that I think accepts darker fiction.
There's a few others you can find by doing a search but if you do a search just check that they're publishing currently and are not old pubs that are abandoned and that they're currently accepting new writers.
You'll find this info in their submission guidelines on how to apply as a new writer. Have fun!