Redefinition of the sexstrigatus group of Lasioglossum (Hemihalictus) Cockerell, 1897 (Hymenoptera, Apoidea, Halictidae), with a revision of Japanese species Author Murao, Ryuki 7E665839-6675-4365-A7EA-169D4E4DA008 Regional Environmental Planning Co., Ltd, 1 - 10 - 12, Muromi, Sawara-ku, Fukuoka, 814 – 0015 Japan. r.murao@mbr.nifty.com text European Journal of Taxonomy 2021 2021-08-18 763 1 74 http://dx.doi.org/10.5852/ejt.2021.763.1463 journal article 4854 10.5852/ejt.2021.763.1463 31f73be9-4a90-4c0a-937e-784437eff4bd 2118-9773 5235968 9823AAD7-1113-434B-9882-1CF885DE7CED Lasioglossum ( Hemihalictus ) smilodon Ebmer & Sakagami, 1994 Figs 9 , 15F , 18D , 20E Lasioglossum ( Evylaeus ) smilodon Ebmer & Sakagami in Ebmer et al ., 1994: 32 , figs 26–33 ( ♀ ♂ ) ( holotype : ELKU, ♀ , type locality =(TOKARA) Suwanose-Jima, Kagoshima Pref. , Japan , examined). Lasioglossum ( Evylaeus ) smilodon – Sakagami & Ebmer 1996 : figs 1c, 3c, 4c, 5b, 6a ( ♀ ♂ ). — Murao et al . 2010: 31–32 (in key). Diagnosis Females are similar to L. ( H. ) ikudomei sp. nov. but are separated from them by the supraclypeal area dimly shiny (IS distinctly tessellate), the PP on the mesoscutum denser (IS= 2 d in maximum) ( Fig. 9E ), and the lineolation of T1 more clear. In contrast, in L . ( H .) ikudomei sp. nov. , the supraclypeal area is more shiny (IS weakly tessellate), the PP on the mesoscutum sparser (IS= 3 d in maximum) ( Fig. 5E ), and T1 with very weak lineolation. Material examined Holotype JAPAN – Ryukyus • ♀ ; Kagoshima Pref. , Suwanose-jima ; 2 Aug. 1985 ; S. Ikudome leg.; ELKU . Paratype JAPAN – Ryukyus • 1 ♂ ; Kagoshima Pref. , Akuseki-jima ; 150–230 m a.s.l. ; 2 Aug. 1985 ; S. Ikudome leg.; KWC . Fig. 9. Lasioglossum ( Hemihalictus ) smilodon Ebmer & Sakagami, 1994 . A . ♀, lateral habitus. B . ♀, head in frontal view. C . ♂, head in frontal view. D . ♀, labrum. E . ♀, mesoscutum. F . ♀, metapostnotum. Scale bars: A = 2 mm; B = 1 mm; C, E–F = 0.5 mm; D = 0.2 mm. Other material JAPAN – Ryukyus • 1 ♀ ; Kagoshima Pref. , Iwo-jima ; 1 May 2011 ; T. Kawano leg.; cMur • 1 ♀ ; Kagoshima Pref. , Ôsumi Is ., Kuchinoerabu-jima ; 21 Jul. 1989 ; H. Watanabe leg.; KWC • 1 ♀ ; Kagoshima Pref. , Kuroshima Is. , Osato ; 4 Sep. 1981 ; Sk. Yamane leg.; KWC • 1 ♂ ; Kagoshima Pref. , Osumi-shotô , Yakushima , Issô ; 30 Jul. 1988 ; Sk. Yamane leg.; KWC • 2 ♀ ; Kagoshima Pref. , Tokara Islands , Takarajima Isl. , Oogomori ; 31 May–4 Jun. 2005 ; T. Mita leg., yellow pan trap ; cMur • 1 ♀ ; Kagoshima Pref. , Tokara Islands , Nakano-shima , Mt On-take ; 7 Jun. 2005 ; T. Mita leg.; cMur • 1 ♀ ; Kagoshima Pref. , Tokara , Nakano-shima , Ikenobaru ; 220 m a.s.l. ; 14 Oct. 1985 ; S. Ikudome leg.; KWC • 1 ♀ ; Kagoshima Pref. , Tokara Islands , Nakano-shima , Toshima ; 21 Jun. 1973 ; H. Makihara leg.; ELKU • 1 ♂ ; Kagoshima Pref. , Tokara , Suwanose-jima ; 50–120 m a.s.l. ; 31 Jul. 1985 ; S. Ikudome leg.; KWC . Redescription Female MEASUREMENTS (n =5, unit mm). BL =4.88–5.75 (5.48± 0.35), WL= 4.50–5.13 (4.80 ± 0.24), HL=1.48– 1.68 (1.59 ±0.07), HW= 1.45–1.61 (1.55± 0.06), IOD =0.26–0.29 (0.28 ± 0.01), OOD=0.24–0.26 (0.25 ± 0.01), OCD= 0.19–0.24 (0.21± 0.02), UOD= 0.87–1.00 (0.95± 0.05), MOD =1.03–1.18 (1.13± 0.06), LOD =0.77–0.90 (0.86 ±0.05), IAD =0.13–0.16 (0.15 ± 0.01), AOD=0.26–0.31 (0.28 ± 0.02), CAL =0.27–0.29 (0.28± 0.01), CPL=0.32–0.35 (0.34± 0.01), EL=1.60–1.85 (1.79± 0.11), EW =0.39–0.45 (0.41 ± 0.03), GW=0.29–0.35 (0.34 ± 0.03), SPL=0.63–0.66 (0.65 ± 0.01), F1L=0.08– 0.10 (0.09 ± 0.01), F2L=0.08–0.11 (0.09 ± 0.01), F3L= 0.08–0.10 (0.08± 0.01), F2W=0.11–0.15 (0.13 ± 0.01), MsW = 1.75–2.05 (1.92 ± 0.12), SCL= 0.38–0.43 (0.41 ± 0.02), MNL=0.23–0.28 (0.26 ± 0.02), MPL =0.28–0.33 (0.31 ± 0.02), MtW= 1.80–2.15 (2.00 ± 0.14). COLORATION. Body black except for the following parts: mandible reddish brown apically; F4–F10 yellowish brown ventrally; tegula yellowish brown translucent; tibial spur yellow; metasomal terga narrowly yellowish brown translucent apically. Wings transparent, veins and stigma blackish brown. PUBESCENCE. Body hairs whitish, and covered with erect and sparse straight or fine branched hairs except for the following parts: pronotal dorsum to lobe and metanotum densely tomentose; hind trochanter, femur, and tibia mixed with plumose hairs, forming scopa. Disc of T1 without short hairs. Discs of T2– T4 with moderately dense short hairs over entire surface. STRUCTURE AND SCULPTURE HEAD. Nearly as long as wide; HW:HL=1:1.02. Vertex rounded in frontal view. MOD:UOD:LOD =1:0.84:0.76. IOD:OOD:OCD =1:0.88:0.76. IAD:AOD =1:1.91. Ocellocular area moderately densely puctate, IS smooth (IS =1–2.5 d). Paraocular area and frons weakly shiny, with shallow reticulate PP. Supraclypeal area slightly convex, weakly shiny, with dense PP, IS weakly tessellate (IS=1–1.5 d). CPL:CAL=1:0.83. Clypeus nearly flat, with dense PP on upper half and larger shallow PP on lower half; IS weakly tessellate on upper half and nearly smooth on lower half (IS= 1–2 d on upper half). EW:GW =1:0.81. Genal area to postgena with straight ridges. Malar space linear. Occiput not carinate. Hypostomal carinae nearly parallel. Mandible bidentate. Labrum ( Fig. 9D ): basal area approximately 1.9 × as wide as long; distal process approximately 0.6 × as long as basal area, narrow, and without lateral projection; distal keel pointed apically. Antenna short, not reaching metasoma. F2L:F2W= 1:1.48; flagellum nearly flattened ventrally. THORAX. Dorsolateral angle of pronotum obtuse; lateral surface without ridges; lateral lobe rounded. Tegula ovoid, nearly smooth. Mesoscutum ( Fig. 9E ) with dense PP over entire surface; IS distinctly tessellate over entire surface (IS =0.5–2 d); parapsidal line a narrow groove. Mesoscutellum with sparser PP on submedian area and denser PP on marginal area; IS weakly tessellate over entire surface (IS =1–4 d on submedian area, and 0.5–2 d on marginal area). Metanotum weakly rugulose. Mesepisternum shallow reticulate-punctate on upper area and weakly rugulae on lower area. SCL:MNL:MPL =1:0.63:0.74. Propodeum: metapostnotum ( Fig. 9F ) dimly shiny and gently inclined, with straight ridges occupying anterior half, and distinctly tessellate on posterior half; junction between metapostnotum and posterior surface not carinate, distinctly tessellate; lateral surface distinctly tessellate; posterior surface with lateral carina on lower half, without oblique carina. Coxae usual shape, without tubercle. Fore trochanter narrow, longer than wide. Basitibial plate of hind leg carinate marginally. Inner hind tibial spur pectinate, with 3–4 teeth as in Fig. 20E (n =4). Fore wing with three submarginal cells. ABDOMEN. Disc of T1 without distinct PP and with weak lineolation over entire surface ( Fig. 15F ). Disc of T2 weakly lineolate on anterior and posterior area, and nearly smooth on medial area. Discs of T3–T4 with weak lineolation over entire surface. Male MEASUREMENTS (n=3, unit mm). BL =4.77–5.38 (4.90 ± 0.36), WL= 3.77–4.46 (4.21± 0.31), HL=1.42– 1.73 (1.60 ±0.13), HW= 1.36–1.76 (1.56± 0.16), IOD =0.27–0.31 (0.30 ± 0.02), OOD=0.27–0.29 (0.27 ± 0.01), OCD= 0.16–0.22 (0.19± 0.03), UOD= 0.89–1.13 (1.00± 0.10), MOD =0.93–1.24 (1.08± 0.13), LOD =0.69–1.02 (0.86 ±0.14), IAD =0.16–0.24 (0.20 ± 0.04), AOD=0.22–0.31 (0.25 ± 0.04), CAL =0.27–0.31 (0.30 ± 0.02), CPL=0.29–0.38 (0.34 ±0.04), EL=1.00–1.24 (1.13± 0.10), EW =0.38–0.47 (0.42 ± 0.04), GW=0.36–0.51 (0.44 ± 0.06), SPL=0.36–0.42 (0.46 ± 0.04), F1L=0.13– 0.16 (0.14± 0.01), F2L= 0.16–0.20 (0.18 ± 0.02), F3L=0.16–0.18 (0.17 ±0.01), F2W=0.13–0.16 (0.15 ± 0.01), MsW = 1.42–1.77 (1.60 ± 0.15), SCL= 0.36–0.42 (0.39 ± 0.03), MNL=0.20–0.22 (0.21± 0.01), MPL =0.27–0.29 (0.28 ± 0.01), MtW= 1.29–1.61 (1.46± 0.13). COLORATION. Body black except for the following parts: lower half or margin dark yellow; mandible reddish brown; labrum dark yellow; pedicel and F1 yellowish brown ventrally; tegula yellowish brown translucent; tibial spur yellow; tarsi yellowish brown or brown; metasomal terga narrowly yellowish brown translucent apically. Wings transparent, veins and stigma blackish brown. PUBESCENCE. Body hairs whitish, and covered with erect and sparse straight or fine branched hairs except for the following parts: pronotal dorsum to lobe and metanotum sparsely tomentose. Disc of T1 with sparse short hairs. Discs of T2–T4 with moderately dense short hairs over entire surface. T2–T3 with thin apical fimbriae, not clear in female. STRUCTURE AND SCULPTURE HEAD. Based on normal specimens (not cephalic polymorphism) Head nearly as long as wide; HW:HL=1:1.03. Vertex rounded in frontal view. MOD:UOD:LOD =1:0.92:0.79. IOD:OOD:OCD =1:0.93:0.65. IAD:AOD =1:1.11. Ocellocular area moderately densely puctate, IS smooth (IS =1–4 d). Paraocular area and frons weakly shiny, with shallow reticulate PP. Supraclypeal area slightly convex, weakly shiny, with moderately dense PP, IS weakly tessellate (IS =1–2.5 d). CPL:CAL=1:0.87. Clypeus nearly flat, with moderately dense PP over entire sutface; IS smooth (IS= 1–3 d). EW:GW =1:1.04. Genal area on lower margin and postgena with straight ridges. Malar space linear. Hypostomal carinae nearly parallel. Mandible edentate. Antenna short, not reaching metasoma. F2L:F2W= 1:0.83; flagellum nearly flattened ventrally. THOARX. Dorsolateral angle of pronotum obtuse; lateral surface without ridges; lateral lobe rounded. Tegula ovoid, nearly smooth. Mesoscutum with dense PP over entire surface; IS weakly tessellate on anterior half, nearly smooth on posterior half (IS =0.5–2 d); parapsidal line a narrow groove. Mesoscutellum with sparser PP over entire surface; IS smooth (IS =1–4 d). Metanotum weakly rugulose. Mesepisternum with moderately dense shallow PP on upper area and weak reticulate PP on lower area; IS smooth. SCL:MNL:MPL= 1:0.53:0.72. Propodeum: metapostnotum weakly shiny and gently inclined, with short straight ridges occupying anterior half and weakly tessellate on posterior half; junction between metapostnotum and posterior surface not carinate, weakly tessellate; lateral surface distinctly tessellate; posterior surface with lateral carina on lower half, without oblique carina. Coxae usual shape, without tubercle. Fore trochanter narrow, longer than wide. Basitibial plate of hind leg carinate marginally. Inner hind tibial spur serrate. Fore wing with three submarginal cells. ABDOMEN. Disc of T1–T3 with fine sparse PP. Disc of T1 basally weakly lineolate or smooth ( paratype and 1 ♂ lineolate, but 1 ♂ not lineolate). Disc of T2–T3 weakly lineolate on anterior and posterior areas, and nearly smooth on medial area. Discs of T4 with weak lineolation over entire surface. S7 with moderately long, apically rounded median process. GENITALIA. Gonobase flat at bottom, ventral arms connected with each other at upper ends; gonocoxite smooth; ventral retrorse lobe tongue-like, moderately long but not reaching gonobase, with sparse short hairs ventrally. Distribution Japan (northern to central Ryukyus: Kuro-shima Is., Iwo-jima Is., Take-shima Is., Yaku-shima Is., Kuchinoerabu-jima Is., Nakano-shima Is., Suwanose-jima Is., Akuseki-jima Is., Takara-jima Is.). Flight period Female: April to October. Male: August to October. The flight records of male are based on the collecting data of the original description ( Ebmer et al . 1994 ). Flower records Ampelopsis glandulosa (Wall.) Momiy. var. hancei (Planch.) Momiy. (Vitaceae) , Artemisia indica Willd. var. maximowiczii (Nakai) H.Hara (Asteraceae) , Psychotria serpens L. ( Rubiaceae ), and Sambucus racemosa L. subsp. sieboldiana (Miq.) H.Hara. (Adoxaceae) .