The stunningly beautiful insects on this page are orchid bees or "Euglossini." Most are in the genus Euglossa and are all from Costa Rica. There are about sixty species of orchid bee in Costa Rica, and a total of 268 species are found between central Mexico and central Brazil.
The bees also visit flowers in the genus Heliconia and the Zingiberaceae family, along with flowering trees like this one in the Solanaceae family.
Orchid bees are not eusocial and do not live in a large colony. However, some females may share their nests with a couple of other females, and a daughter may inherit a nest. In all orchid bee species, the female is the sole provider for the young. She builds the nest, collects pollen and nectar, and raises a handful of young. This photo shows a nest. It is about the size of a small walnut and belongs to a bee in the genus Euglossa. This nest is made from a waxy mix similar to the propolis used by honey bees to plug gaps in their hive. Other species of orchid bees nest in tree cavities.
In this photo, the male bee's rear legs are tucked up in flight position. The port through which he loads perfume is challenging to spot (unless you have a dead bee), but you can see the enlarged tibial area where he stashes his prize.
Male bees pollinate flowers unintentionally. Their focus is on the perfume produced by the flower, tree, or other sources. The bee collects perfumes by dribbling a saliva-like compound rich in lipids on the perfume source. The lipids absorb perfume molecules, and the bee brushes up the mix with his front legs. He then passes the mix rearward and stashes it in a cavity in his rear legs. In this photo, you can see the swollen area where he accumulates his perfume collection.
I don't know what this bee was doing or his species. I'm sure he is a male based on his enlarged rear legs. He was a kilometer or so into the old-growth forest at La Selva Biological Station, where I don't usually see orchid bees. He seemed to be interested in something on a rock. I love his subtle iridescence, which only became visible when my flash fired.
Many orchid bee species spend much of their time high in the forest canopy and are seldom seen. In Costa Rica, a good few species collect pollen, nectar, and perfumes from flowering shrubs and small trees like this member of the verbena family (Stachytarpheta frantzii). The flowers on this plant are also a favorite with hummingbirds.
When not in use, the bee's proboscis is folded under the body, where it protrudes from the rear and may look like a stinger. You can see it clearly in this photo.
I believe the yellow blob on the back of this bee is a pollinium that became attached to the bee when it visited an orchid. Pollinia are produced by orchids and some milkweeds (Asclepias spp.). I have seen orchid bees with pollinia attached on several occasions. With luck, these little packets of pollen will be transferred to the female flower parts during a future visit. It is all a bit tenuous. Like most other bees, orchid bees are essential pollinators. Without them, some species of orchid would no longer be able to reproduce and would, presumably, become extinct. I frequently see tiny white beads of pollen stuck to the setae (hairs) on the bees’ backs. Bees transfer these to the female sex organs of a flower when visiting it, thus fertilizing the flower.
When a female orchid bee collects pollen and nectar, she mixes the two into a nutritious paste which she sticks to the flared area on her rear legs. She then flies the food back to her nest and feeds it to her larva. You can see the paste on the hind legs of this female. You can also see her long proboscis reaching deep into the flower. This extraordinarily long proboscis is a characteristic of orchid bees. The proboscis is sometimes longer than the bee; once deployed, it can reach deep into a flower and the bees use it to draw up nectar.
Most orchid bees I've photographed are in the genus Euglossa, but I'm pretty sure this lovely and large bee is in the genus Eulaema. It was about the size of a bumble bee — almost 1" or around 20mm long. These are slower moving than the Euglossa but seem to be less common.
Male orchid bees spend their 6 or 7-month life span in a near-obsessive search for fragrances. Some species only visit orchids and are the sole pollinator of several species. Others visit a wider array of flowering plants, tree blossoms, tree seeps, resinous trees, and even feces. Females and males are known to "trapline" and visit specific plants on a predictable, daily basis, sometimes arriving within a few minutes of their previous day's visit.
I think these bees are cute as well as stunningly beautiful. Look at this charming little face!
Research conducted in the 1970s indicated that the male bee uses perfume to attract females and/or that females select mates based on the quality and quantity of perfumes. But the bee's method of releasing collected perfumes is not well understood. Some male bees seem to station themselves at "leks." I have seen several bees of two species chasing and buzzing each other at what I assume is a lek. If there were females present, the bees were flying too fast for me to tell them apart from the males. I've also seen Eulaema males station themselves on the side of a tree and buzz as if calling or disbursing perfume. In this case, no females appeared, and the males eventually flew away.
Notes: In my experience, orchid bees are more likely to be found during hotter, dryer months than in the rainy season. Eulaema start their day at dawn. These photographs were taken in Costa Rica between March '22 and March '23. I photographed bees on 33 days during that period. These photos are copyrighted and using them without my permission is theft. If you are an educator, researcher, or you need arthropod photos for a conservation-related project I do not charge for use. However, you will need to send an email to Jeremy Squire, at: secretlives@icloud.com. I will then send you high resolution versions. Licensing rates for other uses are modest.