Mystery and Horror, LLC has posted a new anthology call titled "The Undead of Winter" which is looking for stories of the undead in winter months, holiday stories are welcome for this one. The reading period is August 1 to October 1. Payment is a $5 advance against royalties plus a print copy.
They also have two other anthologies "Strangely Funny" with the reading period now open until June 10 and "All Hallows' Eve" with a reading period of April 20 to July 15. Please note that pay has changed since they first posted these calls to a $5 advance against royalties plus a print copy.
You can find all the details here