Males of this species are quite distinctive, as they are the only Hylaeus with pale projecting hairs on their face. The females are similar to both Hylaeus communis and H. confusus, but have a rather long face, orange colouration on the base of the antennae and yellow markings on the pronotum (front of the thorax). It is not widely distributed in Ireland, with records concentrated in the southeast. It is classed as Vulnerable.

Distribution in Ireland: Primarily a southeastern species, with records concentrated in counties Wicklow, Wexford, Waterford and Cork. A few outliers exist, including Co. Clare and Co. Armagh, but these may be erroneous.

Flight Period: Univoltine, flying from June (occasionally May) until early September.

Habitat: It seems to be mostly associated with coastal habitats in Ireland, including soft-rock cliffs, brownfield sites, scrub but also wooded sites inland.

Flowers Visited: A variety of open-structured flowers, including brambles, Rock Samphire, Wild Carrot, Ox-eye Daisy, Sea Holly and others.

Personal Records: I have only recorded this species twice, at a brownfield site near Wexford town (Co. Wexford), where a single male was feeding on bramble blossom, and at Meeting of the Waters (Co. Wicklow) where a male was encountered basking on a telegraph pole. Hylaeus are one of our more inconsipcuous genera of bee in Ireland and as such are likely to be overlooked. H. hyalinatus is probably present more widely in southern Ireland.