Fire Goat Books is a new publisher with a open submission call for an anthology with the theme, Greco-Roman Mythology. They need flash of 500 to 1500 words and shorts up to 6000 words that are family friendly retellings of the myths. They have prompts at the bottom of the call if you need help. The deadline is August 31 and payment is $15. You can find the details here.
They also have a Winter Solstice themed anthology call. For this one they're looking for stories with a holiday theme of Christmas/New Year. The deadline for this is October 31 and payment is $10. You can find the details here.