I haven't posted one of these in a while but I note that Authors Publish has made some improvements to the formatting for easier reading. Each item is in a box to separate them better and there is now a filter at the top so you can narrow the list to what you are interested in. As usual, the list is a diverse one ranging from calls focussed on specific groups (LGBTQ, BIPOC, others), calls on very specific themes (Cosmic Horror Monthly is paying tribute to the great Catherine L. Moore), and more general calls. We have s-f about plants, creepy Gothic about teeth, open water, and an anthology about social media horror (isn't it horrific enough as it is?).
https://authorspublish.com/45-themed-submission-calls-and-contests-for-march-2026/