Halictus expansifrons Cockerell, T.D.A. 1914. Descriptions and records of bees. LIX. Annals and Magazine of Natural History 8 13: 504–522 [521].
Type data: Syntype(s) BMNH 2? (a specimen is labelled 'type' and has registration number Hym.17.a.946), NSW.
Full description
Diagnosis: Most like L. chapmani. Both sexes: Body black. Female: Frons reticulate-striate, mesoscutum surface shining, densely punctate, dorsal surface of propodeum weakly ruguloso-striolate, weakly defined posterolaterally by carinae. Male: Antennae
moderately long, frons, paraocuiar areas and supraclypeai area with dense hair forming a mat, S4 with 2 median tufts of long plumose hair, tufts weakly separated along midline, hair posterolaterally directed; forewings with 2nd r-m as strong as 1st r-m.
Remarks: See notes for L. chapmani. Five macrocephalic males, including two showing gross enlargement of the head capsule, were examined (one male: NSW. Cobar; 3males: Vic. Kerang; 1male: SA. Wilmington). The measurements of these specimens are as follows: Body
length: 5.78-6.70mm (mean=6.33mm SD=0.40 n=5); Head width: 1.93-2.35mm (n=5); Forewing length: 1.48-1.64mm (mean=1,56mm SD=0.07 n=5). Relative dimensions: HW 100; HL 78-82; UID 65-67; LID 58-64; AOD 18-20; IAD 16-17; OAD 22-24; IOD 19-20; OOD 17-19; CL 18-19; GW 21-26; EW 23-26; ML 41-46; SL 23-27; FL 105-112.
