Yellow faced bees: Hylaeus perspicuus

(Hymenoptera: [Apoidea:] Colletidae: Hylaeinae)

Profile prepared by Karl Magnacca, USGS-BRD, Kilauea Field Station

Hylaeus perspicuus is a large bee endemic to the island of Kauai in Hawaii. It is distinguished by the unique broad, ivory-colored pronotal collar. It is known from only two specimens collected in the 1890’s. It has not been recently collected and may be extinct.

red list profile

conservation status

Xerces Red List Status: Critically Imperiled
Other Rankings:

Canada – Species at Risk Act: N/A
Canada – provincial status: N/A
Mexico: N/A
USA – Endangered Species Act: None
USA – state status: None
NatureServe: GNR
IUCN Red List: N/A

This species is extremely rare; it has not been collected in over 100 years and may be extinct. U.S. Federal listings of rare and endangered species classed H. perspicuus as a “Category 3A” Candidate Species, considered “probably extinct”. It currently has no status as a “Species of Concern” at the federal or state level.

description and taxonomic status

Males: Black, no facial marks; pronotal collar ivory, unusually broad; all tibiae with a full- length ivory stripe. Abdominal punctation distinct.

Females: As in the male. Hylaeus perspicuus is one of the largest Hawaiian species. It is a member of the pubescens species group, but the unusual pronotum makes it unmistakable.

Taxonomic status

Hylaeus perspicuus was described as Nesoprosopis perspicua by Perkins (1899). Nesoprosopis was reduced to a subgenus of Hylaeus by Meade-Waldo (1923). The most recent taxonomic treatment was Daly and Magnacca (2003).

life history

Hylaeus perspicuus probably inhabits wet to mesic forests; the exact habitat of the previous collections is uncertain. Nesting habits are not known, but based on related species it probably nests in wood.


Hylaeus perspicuus was collected by Perkins in the Makaweli area. This region is entirely privately-owned, and no collecting has been done there recently. The species was not encountered in forests to the north, but collecting there has not been extensive either.

threats and conservation needs

The rarity of H. perspicuus and lack of knowledge about its requirements make it difficult to assess threats. Although large areas of native wet forest remains in the Alakai and Kokee areas, the drier regions to the east of Waimea Canyon have been heavily impacted by feral ungulates and invasive plants. Because Makaweli, the type locality of H. perspicuus, is privately owned, it is unknown how much native habitat remains there.

The top conservation needs are to identify extant populations and document the continued existence of the species. The original collection localities of H. perspicuus are not protected; other areas nearby are owned by the State of Hawaii, but may not be managed for conservation.  Research is needed in order to identify reasons for rarity and locate populations.


Daly, H. V., and K. N. Magnacca. 2003. Insects of Hawaii, Vol. 17: Hawaiian Hylaeus (Nesoprosopis) Bees (Hymenoptera: Apoidea). University of Hawaii Press, Honolulu. 234 pp.

Meade-Waldo, G. 1923. Hymenoptera, fam. Apidae, subfam. Prosopidae, fasc. 181. Pp. 1-45 in P. Wytsman (ed.), Genera Insectorum. L. Desmet-Verteneuil, Brussels.

Perkins, R. C. L. 1899. Hymenoptera, Aculeata. Pp. 1-115 in D. Sharp (ed.), Fauna Hawaiiensis, Vol. 1. Cambridge University Press, Cambridge, United Kingdom.

additional resources

Bishop Museum Extinct Species – Insects. Lists H. perspicuus as extinct. Updated March 21, 2002


Magnacca, K. N. 2005. Species Profile: Hylaeus perspicuus. In Shepherd, M. D., D. M. Vaughan, and S. H. Black (Eds). Red List of Pollinator Insects of North America. CD-ROM Version 1 (May 2005). Portland, OR: The Xerces Society for Invertebrate Conservation.