Lasioglossum (Hemihalictus) simplicior ( Cockerell, 1931 )

Murao, Ryuki, 2021, Redefinition of the sexstrigatus group of Lasioglossum (Hemihalictus) Cockerell, 1897 (Hymenoptera, Apoidea, Halictidae), with a revision of Japanese species, European Journal of Taxonomy 763, pp. 1-74 : 24-28

Lasioglossum (Hemihalictus) simplicior ( Cockerell, 1931)

Figs 2D , 8 , 15E , 17D

Halictus simplicior Cockerell, 1931: 16 (holotype:AMNH, ♀, type locality= Shanghai, China, examined).

Lasioglossum (Evylaeus) simplicior – Ebmer 1978b: 316; 1980: 503; 1996: 293. — Takahashi & Sakagami 1993: 275.

Evylaeus (Prosopalictus) simplicior – Pesenko 2007b: 111.

Diagnosis

Females are similar to L. (H.) ohei , but separated from them by the head wider than long (HL/ HW ratio 0.97 ± 0.03), IS of mesoscutum with distinct tessellation over entire surface, and metasomal terga with enamel-like luster. In contrast, in L. (H.) ohei , the head is slightly longer than wide or nearly as long as wide (HL/ HW ratio 1.01 ± 0.02), IS of mesoscutum nearly smooth on posterior margin, and metasomal terga with silky dull luster.

Material examined

Holotype CHINA • ♀; Prov. Kiangsu, Shanghai, Zô-Sè; AMNH.

Other material

JAPAN – Izu Islands • 44 ♀♀; Hachijo Is. , Okago-Fuji ; 26 May 1964; Y. Hirashima and M. Shiga leg.; ELKU • 4 ♂♂; same collection data as for preceding; ELKU • 3 ♀♀; Hachijo Is. , Okago-Sokoto ; 5 Jun. 1964; Y. Hirashima and M. Shiga leg.; ELKU • 1 ♂; same collection data as for preceding; ELKU • 2 ♀♀; Mt Kanto-yama , Hachijo Is. ; 2 Jun. 1964; Y. Hirashima and M. Shiga leg.; ELKU • 1 ♂; same collection data as for preceding; ELKU • 1 ♀; Hachijo Is. , Kamogawa ; 27 May 1964; Y. Hirashima and M. Shiga leg.; ELKU • 2 ♂♂; same collection data as for preceding; ELKU • 15 ♀♀; Hachijo Is. , Mitsune-Kantoyama ; 30 May 1964; Y. Hirashima and M. Shiga leg.; ELKU • 1 ♀; Hachijo Is. , Hachijo Fuji ; 31 May 1964; Y. Hirashima and M. Shiga leg.; ELKU • 1 ♀; Hachijo Is. , Eigo ; 2 Jun. 1964; Y. Hirashima and M. Shiga leg.; ELKU • 1 ♂; same collection data as for preceding; ELKU • 1 ♂; same location as for preceding; 15 Aug. 1987; H. Takahashi leg.; ELKU • 1 ♀; same location as for preceding; 26 Sep. 1987; H. Takahashi leg.; MNHAH • 1 ♀; same location as for preceding; 4 Oct. 1987; H. Takahashi leg.; MNHAH • 1 ♂; Hachijo Is. , Mt Mitsune-yama, Nakanogo-Daigo ; 1 Jun. 1964; Y. Hirashima and M. Shiga leg.; ELKU • 1 ♀; Hachijo Is. , Bouei Road ; 27 Sep. 1987; H. Takahashi leg.; MNHAH • 2 ♂♂; same collection data as for preceding; MNHAH • 3 ♂♂; same location as for preceding; 3 Oct. 1987; H. Takahashi leg.; ELKU • 1 ♀; Hachijo Is. , Okago ; 10 Jul. 1987; H. Takahashi leg.; MNHAH • 1 ♂; Hachijo Is. , Sokoto ; 4 Jun. 1964; Y. Hirashima and M. Shiga leg.; ELKU • 1 ♀; Tokyo, Aoga Is. , Yasundogou ; 10 Aug. 1987; H. Takahashi leg.; MNHAH .

Redescription

Female

MEASUREMENTS (n=6, unit mm). BL =5.25–5.75 (5.41± 0.24), WL= 3.85–5.25 (4.81± 0.52), HL=1.48– 1.58 (1.54 ±0.05), HW= 1.52–1.68 (1.59± 0.07), IOD =0.22–0.31 (0.27 ± 0.03), OOD=0.26–0.33 (0.28 ± 0.03), OCD= 0.13–0.21 (0.18± 0.03), UOD= 0.97–1.03 (1.01 ± 0.02), MOD =1.09–1.23 (1.16± 0.06), LOD =0.82–0.94 (0.88± 0.05), IAD= 0.16 (0.16 ±0.00), AOD= 0.27–0.32 (0.29 ±0.02), CAL =0.22–0.31 (0.28± 0.03), CPL=0.32–0.35 (0.34 ± 0.01), EL= 1.09–1.85 (1.66± 0.29), EW=0.39– 0.45 (0.42 ± 0.02), GW=0.29–0.35 (0.33 ±0.02), SPL=0.60–0.66 (0.64 ±0.02), F1L=0.07–0.10 (0.09 ± 0.01),F2L =0.07–0.08(0.08 ± 0.01), F3L=0.08–0.10(0.09 ± 0.01), F2W= 0.11–0.15(0.13± 0.01), MsW = 1.71–2.00 (1.88 ±0.12), SCL= 0.31–0.43 (0.39 ± 0.05), MNL=0.22–0.28 (0.25± 0.02), MPL =0.24–0.28 (0.26 ±0.01), MtW=1.75–2.05 (1.90 ± 0.11).

COLORATION. Body black except for the following parts: mandible reddish brown apically; flagellum blackish brown ventrally; tegula yellowish brown translucent; tibial spur yellow; metasomal terga broadly yellowish brown translucent apically. Wings transparent, veins and stigma yellowish brown.

PUBESCENCE. Body hairs whitish, and covered with erect and sparse straight or fine branched hairs except for the following parts: pronotum moderately densely tomentose on dorsal area and around lobe; hind trochanter, femur, and tibia mixed with plumose hairs, forming scopa.

STRUCTURE AND SCULPTURE HEAD. Wider than long or nearly as long as wide;HW:HL=1:0.97.Vertex rounded in frontal view. MOD:UOD:LOD= 1:0.87:0.76. IOD:OOD:OCD =1:1.05:0.68. IAD:AOD =1:1.84. Ocellocular and paraocular areas, frons weakly shiny, with shallow reticulate PP. Supraclypeal area slightly convex, dull, with dense PP, IS distinctly tessellate (IS =0.5–2 d). CPL:CAL= 1:0.82. Clypeus nearly flat, with dense PP on upper half and larger shallow PP on lower half, IS nearly smooth (IS=0.5– 1 d on upper half). EW:GW =1:0.78. Genal area with weak straight ridges. Malar space linear. Occiput not carinate. Postgena distinctly tessellate. Hypostomal carinae nearly parallel. Mandible bidentate.

Labrum ( Fig. 8D ): basal area approximately 2.2 × as wide as long; distal process approximately 0.7 × as long as basal area, narrow, and without lateral projection; distal keel pointed apically. Antenna short, not reaching metasoma. F2L:F2W =1:1.71; flagellum nearly flattened ventrally.

THOARX. Dorsolateral angle of pronotum obtuse; lateral surface without ridges; lateral lobe rounded. Tegula ovoid, nearly smooth. Mesoscutum ( Fig. 8E ) with dense PP over entire surface; IS distinctly tessellate over entire surface (IS =0.5–2 d); parapsidal line a narrow groove. Mesoscutellum with dense PP over entire surface, IS with weak tessellation (IS= 0.5–2 d). Metanotum weakly rugulose. Mesepisternum weakly shiny, with reticulate PP over entire surface. SCL:MNL:MPL=1:0.63:0.65. Propodeum: metapostnotum ( Fig. 8F ) gently inclined, with irregular sinuate ridges nearly attaining to posterior margin; junction between metapostnotum and posterior surface not carinate; lateral surface weakly rugulose; posterior surface with lateral carina on lower ⅔, 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 with slender 2–5 teeth (n=50). Fore wing with three submarginal cells.

ABDOMEN.DISC OF T1 WITH SPARSE FINE PP ON MEDIAL AREA AND LINEOLATION OVER ENTIRE SURFACE ( FIG. 15E ). Lineolation on T2–T5 nearly over entire surface.

First description of male

MEASUREMENTS (n=5, unit mm). BL =4.38–5.62 (4.94 ± 0.41), WL= 3.92–5.15 (4.37 ± 0.43), HL=1.44– 1.49 (1.45 ±0.02), HW= 1.51–1.62 (1.56± 0.04), IOD =0.27–0.29 (0.28 ± 0.02), OOD=0.29–0.31 (0.30 ± 0.01), OCD =0.20–0.22 (0.21 ± 0.01), UOD=0.98–1.04 (1.02± 0.03), MOD =1.04–1.11 (1.08± 0.03), LOD =0.80–0.91 (0.85 ±0.05), IAD =0.20–0.22 (0.20 ± 0.01), AOD =0.22–0.24 (0.24 ± 0.01), CAL =0.22–0.24 (0.24± 0.01), CPL=0.31–0.38 (0.34± 0.02), EL=1.07–1.11 (1.08± 0.02), EW =0.44–0.49 (0.46± 0.02), GW=0.36–0.44 (0.40 ±0.03), SPL= 0.42–0.44 (0.44 ± 0.01), F1L=0.11 (0.11 ± 0.00),F2L =0.16–0.18(0.17 ± 0.01),F3L=0.16–0.18 (0.17 ±0.01),F2W= 0.11–0.13(0.13± 0.01), MsW = 1.39–1.55 (1.47 ±0.05), SCL= 0.36–0.38 (0.36 ± 0.01), MNL=0.18–0.20 (0.18± 0.01), MPL =0.22 (0.22 ±0.00), MtW=1.19–1.32 (1.24 ± 0.05).

COLORATION. Body black except for the following parts: mandible yellow except for apically reddish; labrum and lower half of clypeus yellow; flagellum yellowish brown ventrally; tegula yellowish brown translucent; tibiae basally and apically yellow; tibial spur yellow; tarsi yellow; metasomal terga broadly yellowish brown translucent apically. Wings transparent, veins and stigma pale yellowish brown.

PUBESCENCE. Body hairs whitish, and covered with erect and sparse straight or fine branched hairs except for the following parts: lower paraocular area sparsely tomentose.

STRUCTURE AND SCULPTURE HEAD. Wider than long; HW:HL= 1:0.93. Vertex rounded in frontal view. MOD:UOD:LOD =1:0.94:0.78. IOD:OOD:OCD= 1:1.06:0.73. IAD:AOD =1:1.11. Ocellocular and paraocular areas, frons weakly shiny, with shallow reticulate PP. Supraclypeal area nearly flat, dull, with reticulate PP, IS distinctly tessellate. CPL:CAL= 1:0.71. Clypeus nearly flat, with dense PP over entire surface, IS smooth (IS= 0.5–1 d). EW:GW= 1:0.88. Genal area with weak straight ridges. Malar space linear. Occiput not carinate. Postgena distinctly lineolate. Hypostomal carinae nearly parallel. Mandible edentate. Antenna short, not reaching metasoma. F2L:F2W =1:0.74; 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 margin, otherwise smooth (IS=0.5–2 d); parapsidal line a narrow groove. Mesoscutellum with moderately dense over entire surface, IS smooth (IS= 0.5–3 d). Metanotum weakly rugulose. Mesepisternum weakly shiny, with reticulate PP over entire surface. SCL:MNL:MPL=1:0.50:0.61. Propodeum: metapostnotum gently inclined, with longitudinal ridges on anterior ⅔, not reaching posterior margin; junction between metapostnotum and posterior surface not carinate and nearly smooth; lateral surface weakly rugulose; 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 with sparse fine PP and without lineolation. Disc of T2–T3 with denser PP than T1; T2 without lineolation, and T3 posteriorly with weak lineolation. T4 with weak lineolation over entire surface. S7 with moderately long, apically rounded median process.

GENITALIA. Gonobase flat at bottom; gonocoxite smooth; ventral retrorse lobe tongue-like, moderately long reaching gonobasal ventral arm, with sparse short hairs ventrally.

Distribution

Japan (Izu-shotô Islands: Hachijo-jima Is., Aoga-shima Is.), Korean Peninsula, Russian Far East, China.

Flight period

Female: late May to early October.

Male: late May to middle October.

Flower record

Hydrangea macrophylla (Thunb.)Ser. (Hydrangeaceae) .

Comments

The type locality of this species is Shanghai in China, so it is not surprising that L. simplicior is also distributed on the Japanese mainland. Interestingly, Japanese specimens matching the holotype were found only on the Izu Islands and not on the Japanese mainland. In the future, it may be worth while to verify whether the population of the Izu Islands indeed represents L. simplicior , after comparison of the genes of both the continental and Izu Islands populations.

This species has been recorded from Japan ( Takahashi & Sakagami 1993; Goubara et al. 2004; Fukasawa & Miyano 2010). However, these records were excluded from the Japanese bee fauna because of the need to re-examine them ( Tadauchi & Murao 2014; Murao 2020). In the present study, the distribution of this species in Japan was reconfirmed by comparing with the type specimen.

Figures

Fig. 2. A, E. Lasioglossum (Hemihalictus) sexstrigatus (Schenck, 1869). A. ♂, lateral habitus. E. ♀, mesepisternum. — B. L. (H.) taeniolellum (Vachal, 1903), ♂, labrum. — C, F. L. (H.) frigidum Sakagami & Ebmer, 1996. C. ♂, cephalic polymorphism. F. ♀, metasomal terga. — D. L. (H.) simplicior (Cockerell, 1931), ♂, cephalic polymorphism. Scale bars: A = 2 mm; B = 0.2 mm; C, E = 0.5 mm; D, F = 1 mm.

Fig. 8. Lasioglossum (Hemihalictus) simplicior (Cockerell, 1931). A. ♀, lateral habitus. B. ♀, head in frontal view. C. ♂, head in frontal view. D. ♀, labrum. E. ♀, mesoscutum. F. ♀, metapostnotum. Scale bars: A = 3 mm; B–C = 1 mm; D = 0.25 mm; E–F = 0.5 mm.

Fig. 15. 1st metasomal tergum, ♀. A. Lasioglossum (Hemihalictus) frigidum Sakagami & Ebmer, 1996. B. L. (H.) ikudomei sp. nov. C. L. (H.) kiautschouense (Strand, 1910). D. L. (H.) ohei Hirashima & Sakagami, 1966. E. L. (H.) simplicior (Cockerell, 1931). F. L. (H.) smilodon Ebmer & Sakagami, 1994. Scale bars: 1 mm.

Fig. 17. Distribution maps. A. Lasioglossum (Hemihalictus) frigidum Sakagami & Ebmer, 1996. B. L. (H.) kiautschouense (Strand, 1910). C. L. (H.) ohei Hirashima & Sakagami, 1966. D. L. (H.) simplicior (Cockerell, 1931). E. L. (H.) spectrum sp. nov. F. L. (H.) speculinum (Cockerell, 1925).