Rectangular with green inside. Seen at 100x
Kingdom Protist. This organism is somewhat oval-like with a bumpy circular part on the top right. Inside it has small green dots that are likely photosynthetic, and clear dots that range in size. It also has a long tubular bent clear part. This was under a compound microscope.
https://www.britannica.com/topic-browse/Life-and-the-Biosphere/Protists/1
Green lichen in center of photo, distinctive green "horns", visible light tan saprophytes visible around green.
found growing on moist dead oak
information found at https://www.projectnoah.org/spottings/915636004
S Israel, C Arava Valley, near N Ashosh