Lasioglossum contaminatum Walker, 2025

Walker, Kenneth L., 2025, The “ weak-veined ” Lasioglossum in Australia, New Zealand and West New Guinea, with descriptions of three new subgenera (Hymenoptera: Apoidea: Halictidae), Zootaxa 5651 (1), pp. 1-94 : 43-47

Lasioglossum . ( Cnephalictus ). contaminatum (Cockerell 1910) new status

( Figures 5A, 12, 14B, 15C–D, 23A–B, E, 35A–B, 36A–B)

Parasphecodes contaminatus Cockerell 1910a , p: 238 (original description), p. 243 (key); Lucas 1910, p: 149 (catalogue); Meyer 1920: 136 (catalogue); Cockerell 1910b, p: 357 (taxonomy); Hacker 1921, p: 145; Cockerell 1932, p: 212 (catalogue).

Lasioglossum (Callalictus) contaminatum Michener 1965 , p: 170 (generic and subgeneric status change).

Lasioglossum (Austrevylaeus) contaminatum Walker 2022a , p: 15 (subgeneric status change).

Diagnosis. Females of L. contaminatum can be recognised by the combination of: Body length 7.16 (± 0.18 SD) mm ( Fig. 35A). ITS = 1.42 (± 0.03 SD) mm. Median ocellus width/ocellocular distance ratio [MOW:OOD ratio 0.89 (± 0.2 SD)]. Face round (FL/HW ratio 0.86 (± 0.02 SD) Fig. 23A). Body integument amber. Frons, paraocular area, vertex and gena with dense, white tomentum ( Fig. 23A). Mesoscutum with dense tomentum of white hair on mesoscutum lateral and posterior margin (U-shaped) and along inner margins of parapsidal line almost reaching dorsal margin ( Fig. 23B). Metapostnotum almost smooth ( Fig. 23E).

Males of L. contaminatum can be recognised by the combination of: Body length 7.54 (± 0.06 SD) mm ( Fig. 35B). ITS = 1.42 (± 0.02 SD) mm. Face long (FL/HW ratio 1.06 (± 0.02 SD). Median ocellus width/ocellocular distance ratio [MOW:OOD ratio 1.0 (± 0.2 SD)]. Eyes strongly convergent below (UOD/LOD ratio 1.43) ( Fig. 36A). Lower half of frons, paraocular area, vertex and gena with dense, plumose, white tomentum ( Fig. 36A). Moderate cover of simple hair across mesoscutum ( Fig. 36B). Genitalia gonobase widened basally (widest distance versus narrowest distance ratio 1.92; gonostylus:gonocoxite length ratio 0.83, retrorse lobe large, curved ( Figs. 15A–B).

Comments. Lasioglossum contaminatum is similar in integument colour to L. amber but differs by lacking the tomentum on the head and mesoscutum; however, Lasioglossum contaminatum has a similar tomentum pattern on the head and mesosoma as found on L. lorienae but the integument colour is different. Additional characters to distinguish these two species are listed in the female key to species.

Etymology. Cockerell did not provide a reason for the name of this species. However, “contaminate” comes from the Latin word “contaminat” which means “made impure.” Since the integument colouration is so different from almost any other Lasioglossum, Cockerell may have considered the colour to be a “contamination”. The suffix “atum” is Latin implies “having the nature of or pertaining to”. An appropriate translation would be “having an impure colour”.

Syntype of “ Parasphecodes contaminatus ”. AUSTRALIA. Queensland. ♂; Cairns , “Kur, 1.02” Turner Coll. 1910–17 (Type 17.a.625. NHMUK014029923 , NHMUK) .

Additional material examined. AUSTRALIA. Queensland. (4 specimens, 2 ♀, 2 ♂) (1 ♂) same data as Syntype but not a type specimen (Genitalia removed but not associated with specimen. SEMK); (1 ♀) Tully Falls S.F. 900m, 11 km SSW Ravenshoe, 5 Jan–7 Feb 1988, Storey & Dickinson, MDPI Flight Intercept Trap site No: 29B. ( QDPI); (1 ♀) Mt Lewis nr Mossman, 10 June 1985, N.W. Rodd ( AM); (1 ♂) Moses Ck, 4 km NE Mt Finnigan, 14–16 Oct 1980, J.C. Cardale, collected at light ( ANIC) .

Redescription of male, female described for first time

Female. Body length 7.16 (± 0.18 SD) mm. ITS = 1.42 (± 0.03 SD) mm. Head length 1.85 (± 0.04 SD) mm. Head width 1.88 (± 0.03 SD) mm. Wing length 5.58 (± 0.18 SD) mm. (n=2).

Colouration. Body integument amber coloured except supraclypeal area and frons brown, metasoma with T4– T6 dark brown. Labrum light brown. Mandible yellow with reddish-brown apically. Pedicel yellow, Flagellum brown dorsally, light yellow brown ventrally. Pronotal lobe yellow. Tegula red brown, yellow. Wing membrane hyaline, faintly dusky, veins with subcosta light brown, otherwise amber to dark brown. Legs yellow brown ( Figs. 23A–B, E, 35A).

Pubescence. Setae white. Frons, paraocular area, vertex and gena with dense, white tomentum, supraclypeal area and clypeus with sparse cover of erect, white hair ( Fig. 23A). Mesoscutum with dense tomentum of white hair on pronotal angle and lobe, space between pronotal lobe and tegula, mesepisternum in front of episternal groove, mesoscutum lateral and posterior margin and along inner margins of parapsidal line almost reaching dorsal margin, mesoscutellum with two radiating circular hair patterns on either side of midline and metanotum medially ( Fig. 23B). Lateral margin of propodeum with moderate cover of short, white hair. Propodeum posterior face with some erect, white hair. Metafemoral scopa with dense plumose hairs ( Fig. 35A). T1–T2 almost bare, with a few short hairs laterally. T3–T6 with increasing amount of hair but still sparse.

Surface sculpture. Clypeus dull, imbricate over basal two thirds, basal half with small, crowded punctures (IS <PD), apical half with larger, sparse punctures (IS = 3–4 PD). Supraclypeal area imbricate, with dense punctures (IS ≤ 1 PD). Paraocular area reticulate, punctures dense (IS ≤ 1 PD) to crowded (IS = 0 PD). Frons punctate-reticulate, punctures crowded (IS = 0 PD) or dense (IS <1 PD). Ocellocular area smooth ( Fig. 23A). Vertex imbricate, punctures absent or obscure. Gena shining, punctures fine, sparse (IS = 2–4 PD). Tegula mostly shining, impunctate except the base. Mesoscutum shining, anteriorly impunctate, medially with moderately punctures (IS = 3–4 PD), posteriorly with sparse, minute punctures (IS = 2–4 PD), parapsidal areas almost impunctate. Mesoscutellum shining, punctures dense medially (IS ≤ 1 PD), laterally with sparse punctures (IS = 6 PD) ( Fig. 23B). Metanotum shining and becoming weakly rugulose laterally, crowded punctures medially (IS ≤ 1 PD). Metapostnotum almost smooth, weakly rugulose laterally, surface anastomosed to weakly imbricate, posterior margin with carina extending laterally onto posterior surface ( Fig. 23E). Propodeum lateral face smooth, posterior face almost smooth, weakly imbricate, surface smooth, lateral carina basally only, oblique carina absent ( Fig. 23E). Mesepisternum shining, weakly imbricate-rugulose, with sparse punctures (IS = 6 PD). Metepisternum rugulosolineate dorsally, imbricate ventrally. Hypoepimeron inflated, dull, white hair along anterior margin, remainder glabrous, weakly imbricate and impunctate. T1 anterior face shining, impunctate and weakly coriarious. T1 medially shining with small, sparse punctures (IS = 1–4 PD), apically shining and impunctate. T2 disc smooth to weakly coriarious, with sparse punctures (IS = 1–6 PD).

Structure. Face round (FL/HW ratio 0.86 (± 0.02 SD) Fig. 23A). Eyes convergent below [UOD/LOD ratio 1.47 (± 0.02 SD)]. Inner eye margins emarginate. Malar area length versus width ratio as 5.0 ( Fig. 14B). Median ocellus width/ocellocular distance ratio [MOW:OOD ratio 0.89 (± 0.2 SD)]. Clypeus projecting ~55% below suborbital tangent, clypeus length/width ratio 0.80 (± 0.028 SD). Clypeus with distinct apicolateral denticles. Gena narrower than eye. Mandible short, almost reaching opposing clypeal angle. Protibial spur with minutely pectinate serrations except apically longer than width of malus. Inner metatibial spur with two rows of teeth, each row with c. 30 denticulate-serrate, oblique and overlapping teeth, teeth about width of rachis. ITS = 1.68 (± 0.02 SD) mm. Distance between parapsidal line (at the starting point) 0.960 (± 0.04 SD) mm. Pronotal angle obtuse. Mesoscutum length/ width ratio 0.75 (± 0.03 SD). Mesoscutum/mesoscutellum length ratio 2.92 (± 0.18 SD. Mesoscutellum/metanotum length ratio 1.50 (± 0.4 SD). Stigma large, 0.91 mm long, 0.43 mm wide (ratio ~2.12 (± 0.03 SD)), margin in marginal cell convex, marginal cell 1.56 mm long, 0.53 mm wide, free portion slightly more than 2X that subtended by submarginal cells (1.13 mm: 0.51 mm), 1m-cu meets second submarginal cell at 1rs-m, stigma perpendicular goes about middle of third submarginal cell.

Male. Body length 7.54 (± 0.06 SD) mm. ITS = 1.42. (± 0.02 SD) mm. Head length 2.09 (± 0.02 SD) mm. Head width 1.97 (± 0.01 SD) mm. Wing length 6.12 (± 0.16 SD) mm. (n=2).

Colouration. Body integument amber coloured except supraclypeal area and frons brown, metasoma segments tinged with dark brown. Clypeus and labrum yellow. Mandible yellow with reddish-brown apically. Scape, pedicel and F1–F2 yellow, remainder of flagellum tinged brown dorsally, light yellow brown ventrally. Pronotal lobe yellow white. Tegula transparent yellow brown. Wing membrane hyaline, faintly dusky, veins with subcosta light brown, otherwise amber to dark brown. Legs yellow. Setae white ( Figs. 35B, 36A–B).

Pubescence. Frons lower half, paraocular area, vertex and gena with dense, plumose white tomentum, upper half of frons, supraclypeal area and clypeus with moderate to sparse cover of simple, white hair ( Fig. 36A–B). Pronotal angle and lobe, space between pronotal lobe and tegula and mesepisternum in front of episternal groove with dense, white tomentum hair. Moderate cover of simple hair across mesoscutum, sparse along midline, moderate cover between midline and parapsidal lines and along posterior margin, parapsidal areas almost bare ( Fig. 36B), mesoscutellum and metanotum almost bare. Lateral margin of propodeum with moderate cover of long and short, white hair. Propodeum posterior face with some erect, white hair. T1–T2 almost bare dorsally, with a few short hairs laterally. T3–T6 with increasing amount of hair but still sparse.

Surface sculpture. Clypeus dull, imbricate over basal two thirds, basal half with small, dense punctures (IS <1 PD), apical half with larger, sparse punctures (IS = 3–4 PD). Supraclypeal area imbricate, faint, with dense punctures throughout (IS ≤ 1 PD). Paraocular area reticulate, with dense punctures (IS ≤ 1 PD) to crowded (IS = 0 PD). Frons punctate, with crowded (IS = 0 PD) or dense (IS <1 PD) punctures. Ocellocular area with crowded punctures (IS = 0 PD). Vertex with crowded punctures (IS = 0 PD). Gena shining, punctures fine, with crowded (IS = 0 PD) or dense punctures (IS <1 PD). Tegula mostly shining, impunctate except the base with sparse punctures (IS = 3–6 PD). Mesoscutum shining, anteriorly impunctate, medially with moderate, sparse, minute punctures (IS = 2–4 PD), parapsidal areas with dense punctures (IS <1 PD). Mesoscutellum shining, with dense punctures medially (IS ≤ 1 PD), laterally with sparse punctures (IS = 1–2 PD). Metanotum dull and becoming weakly rugulose laterally, with crowded punctures medially (IS ≤ 1 PD). Metapostnotum smooth medially, strongly striate laterally, surface anastomosed to weakly imbricate. Propodeum lateral face smooth, weakly imbricate, posterior face shining, almost smooth, weakly imbricate. Mesepisternum shining, weakly imbricate-rugulose, with sparse punctures (IS = 2–4 PD). Metepisternum rugulosolineate dorsally, imbricate ventrally. T1 anterior face shining, impunctate and weakly coriarious. T1 medially shining with small, sparse punctures (IS = 1–4 PD), apically shining and impunctate. T2 disc smooth to weakly coriarious, with sparse punctures (IS = 1–6 PD).

Structure. Face long (FL/HW ratio 1.06 (± 0.02 SD) Fig. 36A). Eyes convergent below [UOD/LOD ratio 1.40 (± 0.02 SD)]. Inner eye margins emarginate. Median ocellus width/ocellocular distance ratio [MOW:OOD ratio 1.0 (± 0.2 SD)]. Clypeus projecting ~58% below suborbital tangent,clypeal area length/width ratio 1.03 (± 0.02 SD). Clypeus without apicolateral denticles. Flagellomeres, except F1, F2 equal or slightly less than F1 and pedicel combined ( Fig. 5A). F2:F1+pedicel length ratio 0.84. F2:F1 length ratio 1.60. F2 length/width ratio 1.56. F9 length/ width ratio 1.43. Eyes strongly convergent below (UOD/LOD ratio 1.43. Mandible short, almost reaching opposing clypeal angle. Gena narrower than eye. Distance between parapsidal line (at the starting point) 1.01 (± 0.03 SD) mm. Pronotal angle obtuse. Mesoscutum length/width ratio 0.89 (± 0.03 SD). Mesoscutum/mesoscutellum length ratio 3.56 (± 0.2 SD). Mesoscutellum/metanotum length ratio 1.14 (± 0.3 SD). Propodeum lateral and oblique absent. Metapostnotum posterior margin rounded.

Genitalia. Gonobase base recessed medially at bottom, arms ventroapically complete, widened basally (widest distance versus narrowest distance ratio 1.92), gonobase longer than gonocoxite (gonobase:gonocoxite length ratio 1.22), gonocoxite with elongated dorsoapical processes (gonocoxite dorsoapical process:gonocoxite length ratio 0.51), apically truncate, gonostylus:gonocoxite length ratio 0.83, gonostylus glabrous, retrorse lobe large, not reaching gonobase, curved, almost glabrous but with median band of small setae ( Figs. 15A–B).

Range. Occurs in North Queensland from Mt Lewis to Milla Milla ( Fig. 12).

Flight period. This species has been collected in October, January, February and June ( Table 1).

Floral hosts. No floral record available.