Costa Rican Insects
Harvestmen and daddy longlegs are two of the common names applied to Opiliones. This one is the only specimen I've seen and I've not been able to ID him. That's not unusual. There are millions of arthropod species in the remaining areas of tropical wet forests. Not to be too glum, but given the ongoing destruction of these areas, thousands of species will become extinct before they are properly described by scientists.
Beetle. (Family Chrysomelidae suspected.)
Seriously challenging to ID this tiny iridescent green beetle once it rolled itself into a ball -- but it made a nice picture! Family Chrysomelidae is suspected.
Spider building her egg case. She first suspended a leaf from multiple threads of web. In this photo, she is creating the pad on which she will deposit her eggs. She will then cover the eggs with more web and probably draw the sides of the leaves together to form a little packet. She will then leave the leaf hanging with her eggs hidden in the folded leaf. The process takes an hour or two in my experience.
Stalk-eyed fly (Richardia.) This is the male -- the female has shorter stalks. Males use the eye stalks to shove each other about when competing for females. When these flies leave their pupal stage their optic nerves are coiled and their eye stalks are much shorter. They apparently inflate the eye stalks by pumping air into them. Very cool and one of a number of stalk-eyed flies found in lowland Costa Rican forest.
This photo shows an 8-9mm Costa Rican trap jaw ant with her jaws in the open position. Her genus is Odontomachus. If you stretch or enlarge the photo you can see the tiny setae arrayed along the inside of the jaw. If these hairs come into contact with prey her jaws will slam shut. I frequently see these ants (as well as another species of trap jaw) in the forest. They move slowly by ant standards and are relatively easy to photograph.