Hylaeus (bee)


Hylaeus is a large and diverse cosmopolitan genus within the bee family Colletidae.

Description

The genus of bees consists of generally small, black and yellow/white wasp-like species. The resemblance to wasps is enhanced by the absence of a scopa, which is atypical among bees.
Hylaeus carry pollen in the crop, rather than externally, and regurgitate it into the cell where it will be used as larval food. Like most colletids, the liquid provisions are sealed inside a membranous cellophane-like cell lining.
Nests are typically in dead twigs or plant stems, or other similarly small natural cavities, rather than constructing or excavating their own nests as in many other bees.

Distribution and status

A significant diversity of Hylaeus is found in Hawai'i — approximately sixty species are recorded as living there. Hylaeus are the only bees considered native to the islands and most of those are unique to the island chain; the diversity of this genus is far greater in Hawai'i than in all of mainland North America. Many of them are species of concern, and some recorded there are possibly extinct. For example, H. finitimus was last collected 100 years ago, and only ever seen on the island of Kauai.
The Hawaiian bee population and diversity is somewhat fluid — within the past ten to twenty years several Hylaeus species have been found and identified on the islands as new to science. In October 2016, seven species were officially listed as endangered by U. S. Fish & Wildlife, the first bees to ever be placed on the endangered species list.

Selected species

Species of Hylaeus include: