Hylaeus (Prosopis) schwarzii (Cockerell, 1896)

Zarrillo, Tracy A., Stoner, Kimberly A. & Ascher, John S., 2025, Biodiversity of Bees (Hymenoptera: Apoidea: Anthophila) in Connecticut (USA), Zootaxa 5586 (1), pp. 1-138 : 104

Hylaeus (Prosopis) schwarzii (Cockerell, 1896)

Schwarz’s Masked Bee

Notes: Connecticut specimens have been restudied by T. A. Zarrillo who has confirmed that the specimens are morphologically distinct from Connecticut H. aff. nelumbonis material. Our two male vouchers of H. schwarzii have the characteristic shining, impunctate, basal median elevation on the third sternite (S3) as described in Mitchell (1960). We are not able to confirm the elevation on S4 as it is hidden under S3. Our three females have the basal area of T1 piceous, and metanotum long, convex, dull with tessellation, and smooth. Connecticut material morphologically determined as H. schwarzii by experts was sent to York University for DNA barcoding and the queried specimen (and also a putative Maryland H. schwarzii , presumably also another black-colored bee) assigned to BIN: AAX2614, H. nelumbonis (very close to but not identical to the Mississippi H. nelumboni s and the Connecticut H. aff. nelumbonis ). Further integrative taxonomic study is needed to see if red-marked and all-black bees in this complex from Connecticut and elsewhere (e.g., Maryland) are conspecific. If so, this may suggest that H. nelumbonis is variable, with some being all black.Alternative possibilities are that the black putative H. schwarzii from Connecticut and Maryland are a cryptic “new” form minimally diverged (for COI) from H. nelumbonis (and the Connecticut “ H. aff. nelumbonis ”). A more complicated interpretation would be that the Connecticut and Maryland “ H. schwarzii ” are H. schwarzii that have acquired H. nelumbonis mt DNA through past hybridization or some other mechanism.

Material examined: New Haven Co.: Guilford : “Chaffinch Island Park”, 41.26470 —72.67516, 22 August 2009, coll. C. T . Maier , 1 ♂, CAES , det. T. A. Zarrillo 2024, UCMS _ ENT 00052699 ; “ Grass Island ”, 41.267795 - 72.656389, 18-19 June 2011, coll. T . A. Zarrillo , 1 ♀, CAES , det. T. A. Zarrillo 2024, bee bowl near a marsh, UCMS _ ENT 00052698 ; 9 July 2011, coll. T . A. Zarrillo , 1 ♀, CAES , det. T. A. Zarrillo 2024, netted from Rosa rugosa near a marsh, UCMS _ ENT 00052657 ; 41.2684, -72.6609, 18-19 June 2011, coll. T . A. Zarrillo , 1 ♂, CAES , det. T. A. Zarrillo 2024, bee bowl on beach dunes, UCMS _ ENT_00052690; 7 July 2012, coll. T . A. Zarrillo , 1 ♀, CAES , det. T.A. Zarrillo 2024, netted from Rosa rugosa, UCMS _ENT 00052695.

HALICTIDAE