Research Article |
Corresponding author: Jason Gibbs ( jason.gibbs@umanitoba.ca ) Academic editor: Thorleif Dörfel
© 2022 Jason Gibbs, Amber Bass, Katherine Morgan.
This is an open access article distributed under the terms of the CC0 Public Domain Dedication.
Citation:
Gibbs J, Bass A, Morgan K (2022) Habralictus and Lasioglossum of Saint Lucia and Saint Vincent and the Grenadines, Lesser Antilles (Hymenoptera, Apoidea, Halictidae). ZooKeys 1089: 125-167. https://doi.org/10.3897/zookeys.1089.72645
|
The new species and the first halictid bees documented from Saint Lucia Habralictus reinae, Lasioglossum (Dialictus) luciae, and L. (Habralictellus) delphiae are described. A fourth species, L. (D.) dominicense, is tentatively recorded from the island. The species are illustrated and compared to similar ones from the Lesser Antilles. Lasioglossum and Habralictus from neighbouring Saint Vincent and the Grenadines are reviewed and a key to Lasioglossum provided, including the description of another new species, L. (Dialictus) gemmeum. Trigona nigrocyanea Ashmead and Dufourea subcyanea Ashmead are synonymised under Lasioglossum cyaneum (Ashmead). Notes on the obscure Lasioglossum (Dialictus) minutum (Fabricius) are provided. A new name, Lasioglossum (Homalictus) minuens, is provided for a secondary homonym Homalictus minutus Pauly. The potential for additional species richness in Saint Lucia and the Lesser Antilles is briefly discussed.
Anthophila, Caribbean, Halictinae, new species, sweat bees, taxonomy
The bees of the Caribbean Islands have received sporadic attention from melittologists. Despite the idyllic landscape of these islands, the lack of species richness may have dissuaded many researchers from visiting. However, specimens accumulated in museum collections have allowed for some recent studies on the regional bee fauna. Bees on the major islands in the Greater Antilles, Cuba, Hispaniola, and Puerto Rico, have been documented relatively well (
The numerous small islands that make up the Lesser Antilles are generally less well-known for bees. Recent studies in the French West Indies, Guadeloupe and Martinique, have documented bees in the Apidae and Megachilidae (
Saint Lucia is an island of similar size (617 km2) to Dominica (750 km2), which lies between Martinique and Saint Vincent and the Grenadines (SVG). Saint Lucia currently has a rather depauperate faunal list of six bee species (
Many specimens from various collections have been examined for taxonomic studies of Caribbean Halictidae, particularly Lasioglossum but also Habralictus (
Species descriptions follow the format of recent papers on Caribbean Lasioglossum (
Measurements for head length, head width, clypeal length, lower interocular distance (LOD), and upper interocular distance (UOD) follow
Habralictus Moure 1941: 59. Type species: Habralictus flavopictus Moure 1941, by original designation
Zikaniella Moure 1941: 57. Type species: Zikaniella crassiceps Moure 1941, by original designation
Saint Lucia • Micoud District • Quilesse Forest Reserve, Laporte, 13.8404, -60.9741, 272 m, 5–7.V.2009, leg. I.A. Foley and R.C. Winton, UV light trap (♂
Saint Lucia • Castries District • Barre de l’Isle, 13.93682, -60.95936, 340 m, 25–28.VI.2009, leg. E.A. Ivie, UV light trap (1 ♀
Males of H. reinae can be distinguished from other Habralictus in the Lesser Antilles by the combination of head narrow (length/width ratio = 1.0–1.07) (length/width ratio = 0.84–0.85 in H. antillarus), clypeus with distal maculation 1/3–1/2 longitudinal length (< 1/5 length in H. antillarus), supraclypeal and lower paraocular areas polished due to lack of microsculpture (distinctly imbricate in H. gonzalezi), mesoscutal punctation indistinct (fine but distinct in H. claviventris and H. insularis); mesepisternum polished with only weak microsculpture, sparse punctures distinct (dull, indistinctly punctate in H. gonzalezi).
Females of H. reinae can be recognised by the combination of head wide (length/width ratio = 9.0) (length/width ratio = 0.92–0.97 in H. gonzalezi), clypeal punctures not distinct (distinctly punctate in H. insularis), clypeal maculation ½ length of clypeus (1/3 in H. antillarus) and T3 sparsely punctate (Fig.
Female (n = 2). Length 4.3–4.5 mm; head length 1.1 mm; head width 1.2 mm; intertegular distance 0.86–0.89 mm; wing length 1.6–1.8 mm.
Colouration. Head and mesosoma bright metallic blue-green with golden and bronze reflections. Clypeal apex pale brownish yellow, base bronze. Labrum reddish brown. Mandible yellow with black base and red apex. Scape yellow ventrally, brown dorsally. Flagellum dark brown, F2-F11 orange-brown ventrally. Pronotal lobe brown. Tegula yellowish brown. Wing membrane faintly dusky, veins brown to dark brown. Legs with varying brown and yellow, brown primarily on coxa, femur and meso- and metatibiae, yellow on trochanters, profemur apex, protibia and protarsi, dorsal or anterior surface of mesotibia, and posterior surface of metatibia and variably on posterior surface of metafemur, Metasoma brown and yellow-orange, yellow-orange on base of terga and on sterna, apical terga brown.
Pubescence. Body with sparse pilosity, dull white to faintly yellowish, dark setae on meso- and metatibia, and scattered on T4–T6. Tomentum on pronotal dorsolateral angles and lobe. Mesoscutal pilosity sparse erect. Wing setae dark. T1 without appressed fan. Terga with sparse setae, absent on apical impressed areas.
Surface sculpture. Clypeal punctures indistinct, sparse (IS = 2–4 PD), denser along apical margin (IS = 1–2 PD), interspaces granular. Face granular with indistinct punctation. Gena imbricate. Tegula punctures obscure. Mesoscutum and mesoscutellum granular with indistinct punctation. Metapostnotum granular, microreticulate basally becoming imbricate toward margin. Mesopleuron granular (imbricate). Propodeal lateral face imbricate, sparsely punctate; posterior face imbricate, sparsely punctate. Metasomal terga finely coriarious. sparse setose punctures (IS = 3–6 PD) along premarginal line of T2-T4 and disc of T3-T5, apical impressed areas impunctate.
Structure. Face length/width ratio 0.78 (± 0.01 SD). UOD/LOD ratio 1.06 (± 0.11 SD). Clypeus projecting ~75% below suborbital tangent; apicolateral denticles rounded knobs. Supraclypeal area length/width ratio 0.97 (± 0.11 SD). Hypostomal carinae parallel. Pronotal angle obtuse. Mesoscutum length/width ratio 0.91 (± 0.06 SD); mesoscutum/mesoscutellum length ratio 2.93(± 0.33 SD); mesoscutellum/metanotum length ratio 1.73 (± 0.13 SD); metanotum/metapostnotum length ratio 0.5 (± 0.03 SD). Lateral propodeal carinae reaching dorsolateral slope; oblique carina absent. Tegula shape ovoid. Forewing with 3 submarginal cells. Distal hamuli arranged 2-1-2. Inner metatibial spur pectinate, with 3 branches not including apex of rachis, proximal branch much longer than width of rachis. Metasoma ovoid, dorsoventrally flattened, apical impressed area medially ~ 1/2 longitudinal length of basal area.
Male (n = 3). Length 4.0–4.3 mm; head length 0.98–1.06 mm; head width 0.94–1.05 mm; intertegular distance 0.65–0.71 mm. Similar to female with usual sex associated modifications.
Colouration. Head and mesosoma iridescent blue-green. Clypeus pale yellow on apical third. Labrum pale yellow. Mandible pale yellow, orange apically. Flagellum brown, F3-F11 yellowish brown ventrally. Pronotal lobe brown. Tegula translucent amber. Wing membrane faintly dusky, veins dark brown. Pro- and mesoleg yellow, except coxa dark with weak metallic reflections, femora ventrally and mesotibia infused with brown. Meta leg brown, except coxa metallic, and trochanter, apices and bases of femur and tibia, and tarsi yellowish brown. Metasoma brown, apical impressed areas reddish brown.
Pubescence. Body pilosity sparse, dull white to faintly yellowish. Gena with long setae (2–2.5 OD). Pronotal lobe with tomentum on posterior margin. Mesoscutal setae sparse, short (0.5 OD). Metasomal terga largely bare; sternal setae sparse (1–1.5 OD), moderately plumose, sparse, erect. Wing setae dark, short, sparse.
Surface sculpture. Clypeal punctures sparse (IS = 1–2 PD), interspaces shiny, weakly imbricate. Supraclypeal punctures sparse (IS = 1–3 PD), interspaces shiny, weakly imbricate. Lower paraocular punctures sparse (IS = 1–3 PD), interspaces shiny, weakly imbricate. Frons and upper paraocular area granular. Gena punctulate-polished; postgena shiny, weakly imbricate. Tegula mostly impunctate. Mesoscutal punctation indistinct, interspaces granular. Mesoscutellar punctation moderately sparse (IS = 1–1.5 PD), interspaces strongly imbricate. Metanotum punctate, interspaces imbricate. Metapostnotum finely reticulate-granular. Pre-episternum imbricate. Hypoepimeral area punctate (IS = 1–1.5 PD), interspaces shiny imbricate. mesepisternum finely punctate (IS = 1–4 PD), interspaces shiny imbricate. Metepisternum imbricate. Propodeum imbricate. Metasoma sparsely punctate (IS = 5–10 PD), apical impressed areas impunctate, interspaces coriarious.
Structure. Face length/width ratio 0.86 (± 0.05 SD). F1: pedicel length ratio 1.1. F2:F1 length ratio 2.5. Gena narrower than eye. Hypostomal carinae parallel. Pronotal angle obtuse. Mesoscutum length/width ratio 0.97 (± 0.03 SD); mesoscutum/mesoscutellum length ratio 2.96 (± 0.05 SD); mesoscutellum/metanotum length ratio 1.92 (± 0.14 SD); metanotum/metapostnotum length ratio 0.5 (± 0.03 SD). Lateral propodeal carina nearly reaching dorsal margin; oblique carina absent. Tegula ovoid. Forewing with 3 submarginal cells. Metatibial spurs ciliate. Metasoma slender, clavate, widest at T4.
This brilliant, shining bee is appropriately named for Reina Rybuck, a curious and inquisitive girl who loved insects. Her light shone bright but too briefly. She is remembered with love and affection by those who knew her.
Of the five Habralictus species known from the Lesser Antilles, all seem to be limited to higher elevations (272–762 m) on the islands (
Augochlora claviventris (1900: 217). Saint Vincent – windward side. 1500 feet. Holotype male by monotypy (NHMUK: BMNH 17.a.1037).
Augochlora claviventris
:
Habralictus claviventris:
Currently only known from the holotype male.
Habralictus claviventris Ashmead, 1900, holotype male A dorsal habitus B face, oblique frontal view C dorsal view of metasoma and tergum 1 D dorsolateral view of metasoma. Images courtesy of the Trustees of the Natural History Museum, London (https://creativecommons.org/licenses/by/4.0/).
Paralictus
Dialictus Robertson, 1902a: 48. Type species: Halictus anomalus Robertson, 1892, by original designation and monotypy
Chloralictus Robertson, 1902c: 248. Type species: Halictus cressonii Robertson, 1890, by original designation
Halictus (Gastrolictus) Ducke, 1902: 102. Type species: Halictus osmioides Ducke, 1902, by monotypy
Halictomorpha Schrottky, 1911: 81. Type species: Halictomorpha phaedra Schrottky, 1911, by original designation
Rhynchalictus Moure, 1947: 5. Type species: Rhynchalictus rostratus Moure, 1947, by original designation
Halictus (Smeathhalictus)
Lasioglossum (Afrodialictus)
Gnathalictus
Evylaeus (Viridihalictus)
Evylaeus (Glauchalictus) Pesenko, 2007: 26. Type species: Halictus problematicus Blüthgen, 1823, by original designation
Evylaeus (Virenshalictus) Pesenko, 2007: 26. Type species: Hylaeus virens Erichson, 1835, by original designation
Evylaeus (Loethalictus) Pesenko, 2007: 26. Type species: Halictus loetus Brullé, 1840, by original designation
Evylaeus (Aerathalictus) Pesenko, 2007: 27. Type species: Melitta aerata Kirby, 1802, by original designation
Saint Lucia • Castries District • Piton Flore, Station no. 26, 10.I.1975, leg. J. Hance & G. Whitmyre (♂ FSCA).
Saint Lucia • Castries District • Castries, 0–210 m, VIII.1976, N.L.H. Krauss (2 ♀
Lasioglossum luciae is one of only two L. (Dialictus) known from St. Lucia. It can be distinguished from L. (D.) dominicense by the larger size and longer head. It resembles L. kilpatrickae Gibbs, 2016 from Dominica and both L. plumbeum (Ashmead, 1900) and L. sanctivincenti (Ashmead, 1900) from Saint Vincent and the Grenadines.
Females of L. luciae and L. kilpatrickae are very similar and definitive characters for distinguishing them are not currently known. The gena of L. luciae may be more distinctly lineolate (Fig.
The male of L. luciae differs from L. kilpatrickae by the less abundant tomentum of the face (Fig.
Female (n = 2). Length 5 mm; head length 1.4 mm; head width 1.4 mm; intertegular distance 1.0 mm; wing length 1.7 mm.
Colouration. Head and mesosoma dull metallic blue-green. Clypeal apex dark brown, base yellow. Labrum reddish brown to orange. Mandible orange with black base and red apex. Flagellum dark brown, F2-F11 orange-brown ventrally. Pronotal lobe reddish brown. Tegula reddish brown. Wing membrane hyaline, veins with subcosta brown to dark brown, otherwise amber. Legs brown, except medio- and distitarsi and portions of metabasitarsus reddish brown. Metasoma blackish brown, apical impressed area reddish brown.
Pubescence. Body with sparse pilosity, dull white to faintly yellowish. Tomentum on gena near eye, pronotum dorsolateral angles and lobe, narrow basolateral patches of T2–T3 and sparsely on T4. Mesoscutal pilosity sparse, erect. Wing setae dark. Acarinarial fan complete, dense. T2 fringes absent, sparse laterally, T3 fringes absent, sparse laterally.
Surface sculpture. Clypeal punctures sparse (IS = 1–4 PD), becoming moderately dense in basal third (IS = 1–2 PD), interspaces polished. Supraclypeal area punctures sparse (IS = 1–3 PD), interspaces weakly imbricate. Paraocular area punctures dense (IS < 1 PD), except near antenna, interspaces imbricate. Frons punctures contiguous. Vertex punctures sparse, interspaces polished. Gena lineolate, postgena lineolate. Tegula punctures obscure. Mesoscutal punctures moderately dense (IS = 1 PD), becoming sparser submedially (IS = 1–1.5 PD) and denser laterad of parapsidal lines (IS ≤ 1 PD), interspaces imbricate, polished laterally; mesoscutellar punctures as in mesoscutum with submedial impunctate area, interspaces imbricate. Metapostnotal rugae strong, anastomosing or subparallel, reaching margin, sculpture imbricate. Pre-episternum rugulose-punctate. Hypoepimeral area densely punctate, interspaces polished. Mesepisternum distinctly punctate. Metepisternum lineolate dorsally, reticulate ventrally. Propodeal lateral face imbricate, sparsely punctate; posterior face imbricate, sparsely punctate. T1 anterior face coriarious; T1 dorsal surface punctures moderately dense (IS = 1–3 PD), absent or very sparse in large apicolateral oval patches, interspaces polished. T2 disc punctures moderately dense (IS = 1–3 PD), interspaces polished, rim impunctate, surface weakly coriarious.
Structure. Face length/width ratio 0.86 (± 0.01 SD). UOD/LOD ratio 1.21 (± 0 SD). Clypeus projecting ~75% below suborbital tangent; apicolateral denticles rounded knobs. Supraclypeal area length/width ratio 2.06 (± 0 SD). Hypostomal carinae parallel. Pronotal angle obtuse. Mesoscutum length/width ratio 0.83 (± 0.01 SD); mesoscutum/mesoscutellum length ratio 2.63 (± 0.1 SD); mesoscutellum/metanotum length ratio 1.66 (± 0.01 SD); metanotum/metapostnotum length ratio 0.75 (± 0.04 SD). Lateral propodeal carinae nearly reaching dorsal margin; oblique carina distinct. Tegula shape ovoid. Forewing with three submarginal cells. Distal hamuli arranged 2-1-2. Inner metatibial spur pectinate, with four branches not including apex of rachis, proximal branch much longer than width of rachis. Metasoma ovoid, apical impressed area medially ~ 1/2 longitudinal length of basal area.
Male (n = 3). Length 4.4–4.5 mm; head length 1.30–1.35 mm; head width 1.29–1.30 mm; intertegular distance 0.87–0.94 mm. Similar to female with usual sex-associated modifications.
Colouration. Head and mesosoma blue-green. Clypeal apex reddish brown. Labrum reddish brown. Mandible brown, orange apically. Flagellum brown, light brown ventrally. Pronotal lobe reddish brown. Tegula orange. Wing membrane hyaline, veins dark brown. Legs brown with reddish brown tarsi. Metasoma blackish brown, apical impressed areas reddish brown.
Pubescence. Body sparse pilosity, dull white to faintly yellowish. Tomentum moderately dense on lower paraocular area, sparse on clypeus, dense on pronotal lobe. Mesoscutal pilosity thin. Sternal pilosity short (1 OD), moderately plumose, sparse, erect. Wing setae dark, short, sparse.
Surface sculpture. Clypeal punctures dense (IS ≤ 1 PD), interspaces polished. Supraclypeal area punctures sparse (IS = 1–2 PD), interspaces polished. Paraocular area punctures dense (IS ≤ 1 PD), interspaces weakly imbricate around antenna socket, otherwise shiny. Frons punctate-reticulate. Gena punctulate-lineolate, postgena sculpture lineolate. Tegula mostly impunctate. Mesoscutal punctation moderately sparse medially (IS = 1–2 PD), denser laterad of parapsidal lines, interspaces weakly imbricate, polished laterally. Mesoscutellar punctation moderately sparse (IS = 1–2 PD), becoming denser on margins. Metanotum punctate. Metapostnotum incompletely rugulose, margin weakly tessellate. Pre-episternum sculpture punctate. Hypoepimeral area closely punctate (IS ≤ 1 PD), interspaces polished. Mesepisternum distinctly punctate (IS ≤ 1 PD), interspaces shiny. Metepisternum lineolate dorsally, punctate-reticulate ventrally. Propodeal lateral face tessellate-punctate, dorsolateral slope punctate. Propodeal posterior face sculpture tessellate-punctate. T1 anterior face weakly coriarious. T1 dorsal surface evenly punctate (IS = 1–2 PD), interspaces shiny. T2 disc punctures sparse (IS = 1–2.5 PD), interspaces shiny, apical impressed area impunctate, interspaces coriarious.
Structure. Face length/width ratio 0.87–0.88. F1: pedicel length ratio 1.27. F2:F1 length ratio 1.5. Gena narrower than eye. Hypostomal carinae parallel. Pronotal angle obtuse. Mesoscutum length/width ratio 0.82–0.85; mesoscutum/mesoscutellum length ratio 2.44; mesoscutellum/metanotum length ratio 1.78; metanotum/metapostnotum length ratio 0.77. Propodeum lateral carina nearly reaching dorsal margin; oblique carina absent. Tegula ovoid. Forewing with 3 submarginal cells. Metatibial spurs ciliate. Metasoma slender, parallel sided.
The specific epithet is derived from the name of the island. Saint Lucia is the only sovereign nation named after a historical woman.
Males are associated with females in part by the shared head length consistent with patterns seen between L. dominicense and L. kilpatrickae in Dominica.
Lasioglossum (Dialictus) dominicense
Saint Lucia • Dauphin District • Louvette trap site, 13.9689, -60.8859, 25–29.VI.2009, leg. M.L. Gimmel and C.A. Maier, UV light trap (1 ♀
We ascribe the Saint Lucia material to L. dominicense without supporting evidence to the contrary. Although there seems to be some pattern of distinct species across islands in the Lesser Antilles, we are unable to confidently differentiate females of L. dominicense from Saint Lucia and Dominica at this time. As a lowland species occurring near the beach, it is most consistent with a multi-island distribution. Additional comparative study including males, specimens from Martinique, and molecular data would be useful.
Habralictellus
Moure & Hurd, 1982. Type species: Halictus auratus
Saint Lucia • Micoud District • Escap Community Fond Bay at beach, [13 83.16 60 89.30], 1 m, 8.V.2009, leg. C.M. Delphia, J.B. Runyon (♀
Lasioglossum delphiae is easily distinguishable as a member of the subgenus Habralictellus. It has two submarginal cells (1rs-m absent). It closely resembles L. (H.) roseauense from Dominica. Lasioglossum delphiae has the mesoscutellum very weakly sculptured, almost polished with distinct, sparse punctures (mesoscutellum dull, sculpturing stronger, similar to that of mesoscutum in L. roseauense) and the metasomal terga have orange bands basally (all dark in L. roseauense). There is more yellow on the foreleg of L. delphiae than L. roseauense, although such colour characters may not be reliable given the limited material available.
Female (n = 2). Length 4.5 mm; head length 1.1–1.2 mm; head width 1.2–1.3 mm; intertegular distance 0.9–1.04 mm; wing length 1.7–1.8 mm.
Colouration. Head and mesosoma dull metallic golden-green, metapostnotum blue-green. Clypeal apex reddish brown. Labrum reddish brown to orange. Mandible orange with black base and red apex. Scape brown apically, orange basally. Flagellum brown, F3-F11 orange-brown ventrally. Pronotal lobe reddish brown. Tegula amber. Wing membrane hyaline, veins brown. Legs brown, except orange on pro- and mesotrochanters, protibia, protarsi, ventral surface of mesotibia, mesotarsi 2–5, and apices of metafemur and metatibia. Metasomal terga reddish brown with orange patches basally on terga.
Pubescence. Body with sparse pilosity, dull white to faintly yellowish. Tomentum on pronotal dorsolateral angles and lobe. Mesoscutal pilosity sparse erect. Wing setae dark. Acarinarial fan absent, only sparse erect setae on anterior face of T1. Terga with only sparse setae, without apical fringes or basal tomentum.
Surface sculpture. Clypeal punctures sparse (IS = 1–2.5 PD), interspaces weakly imbricate almost polished on apical half, basally tessellate-granular. Supraclypeal punctures sparse (IS = 1–3 PD), interspaces finely reticulate-granular. Paraocular area punctures sparse (IS = 1–2.5 PD), interspaces granular. Frons punctures indistinct, sparse (IS = 1–3 PD). Vertex granular. Gena lineolate, postgena lineolate. Tegula finely punctate on anterior half (IS = 1–2.5 PD), interspaces imbricate, posterior half glabrous. Mesoscutal punctures sparse (IS = 2–3.5 PD), interspaces tessellate; mesoscutellar punctures coarser, sparse (IS = 2–4 PD), interspaces shiny imbricate. Metanotum granular. Metapostnotum transversely lineolate at base, imbricate along apical margins. Preëpisternum tessellate-granular. Hypoepimeral area indistinctly punctate, interspaces tessellate-granular. Mesepisternum indistinct, sparsely punctate (IS = 1–3 PD), interspaces tessellate-granular. Metepisternum lineolate dorsally, imbricate ventrally. Propodeal lateral face tessellate-imbricate, sparsely punctate; posterior face imbricate, sparsely punctate. T1 anterior face polished, dorsally coriarious. T2-T5 sparsely punctate, interspaces coriarious.
Structure. Face length/width ratio 0.77 (0.01 SD). UOD/LOD ratio 1.18 (± 0 SD). Clypeus projecting ~70% below suborbital tangent; apicolateral denticles low rounded knobs. Supraclypeal area length/width ratio 0.7 (± 0.01 SD). Hypostomal carinae parallel. Pronotal angle obtuse. Mesoscutum length/width ratio 0.83 (± 0.04 SD); mesoscutum/mesoscutellum length ratio 2.7 (± 0.09 SD); mesoscutellum/metanotum length ratio 1.98 (± 0.1 SD); metanotum/metapostnotum length ratio 0.57 (± 0.06 SD). Propodeum lateral carinae reaching halfway to dorsal margin; oblique carina absent. Tegula shape ovoid. Forewing with two submarginal cells. Distal hamuli arranged 2-1-2. Inner metatibial spur pectinate, with four branches not including apex of rachis, proximal branch much longer than width of rachis. Metasoma ovoid, apical impressed area medially ~ 1/2 longitudinal length of basal area.
The species is named for Casey Delphia for her kind support of JG’s studies of Caribbean bees generally and in appreciation for collecting the specimens above and bringing them to his attention.
Lasioglossum delphiae was collected from dry forest/beach habitats near the coast (C. Delphia, in litt.).
Halictus cyaneus
Dufourea subcyanea
Trigona nigrocyanea
Dufourea subcyanea:
Halictus cyaneus:
Dialictus cyaneus:
Dialictus nigrocyaneus:
Dialictus subcyaneus;
Lasioglossum cyaneum:
Trigona nigrocyanea:
SVG • Saint Vincent • Saint Vincent (Halictus cyaneus syntypes 1 ♀ 1 ♂
Lasioglossum (Dialictus) cyaneum (Ashmead), syntype female of Halictus cyaneus Ashmead A dorsal habitus B head, frontal view C lateral habitus. Images courtesy of the National Museum of Natural History, Smithsonian Institution. https://collections.nmnh.si.edu/search/ento/
Lasioglossum (Dialictus) cyaneum (Ashmead), syntype male of Halictus cyaneus Ashmead A dorsal habitus B head, frontal view C lateral habitus. Images courtesy of the National Museum of Natural History, Smithsonian Institution. https://collections.nmnh.si.edu/search/ento/
Lasioglossum cyaneum is structurally similar to L. plumbeum and L. sanctivincenti but is easily recognisable by the entirely blue body and dark wing venation. The male T1-T6 are blue on the disc and dark reddish brown on the lateral and apical margins. The head is distinctly shorter (female and male face length/head width = 0.82–0.85) than L. plumbeum (male face length/head width = 0.87–0.90). Both Dufourea subcyanea and Trigona nigrocyanea were described from single males in the same publication with Halictus cyaneus. The former differs from L. cyaneum only in the absence of vein 1rs-m, leading to two submarginal cells rather than three. Loss of this vein is relatively common in L. (Dialictus) (
Lasioglossum (Dialictus) cyaneum (Ashmead), syntype male of Trigona nigrocyanea Ashmead A dorsal habitus B head, frontal view C lateral habitus. Images courtesy of the Trustees of the Natural History Museum, London (https://creativecommons.org/licenses/by/4.0/). Photographs by David Notton.
Halictus plumbeus
Halictus plumbeus:
Halictus (Chloralictus) plumbeus:
Dialictus plumbeus:
Lasioglossum plumbeum:
SVG • Saint Vincent • St. Vincent, leg. H.H. Smith (Halictus plumbeus syntypes 1 ♀ NHMUK, 1 ♀
Lasioglossum (Dialictus) plumbeum (Ashmead), syntype female of Halictus plumbeus Ashmead A dorsal habitus B head, frontal view C lateral habitus. Images courtesy of the National Museum of Natural History, Smithsonian Institution. https://collections.nmnh.si.edu/search/ento/
Lasioglossum sanctivincenti is quite similar to L. plumbeum. The most striking difference is the darker blue colour of the head and mesosoma of L. plumbeum. Lasioglossum sanctivincenti has a shorter head (face length/head width ratio = 0.82 SD 0.02) than L. plumbeum (0.86 SD 0.01). Mesoscutal puncture density is subtly different between the two species. In L. sanctivincenti punctures laterad of the parapsidal line are dense, but distinctly separated. These are nearly reticulate in L. plumbeum, without clear interspaces. Immediately mesad of the parapsidal line, L. sanctivincenti has distinctly separated punctures (IS ≤ 1 PD), but these are denser in L. plumbeum (IS ≤ 0.5 PD).
Halictus sancti-vincenti
Halictus santivincent:
Halictus sancti-vincenti:
Halictus (Chloralictus) sanctivincenti:
Dialictus sanctivincenti:
Lasioglossum sanctivincenti:
SVG • Grenadines • Canoun Island, 7.X.1991, leg. R.E. Woodruff (3 ♀ FSCA). Bequia Island, 1966–VI.1967, leg. Badger (1 ♀ UNSM). Grenada • Carricou Island, Hillsborough, the Sands Guest House, 1.III.1990, leg. R.E. Woodruff (1 ♀ FSCA) • St. Andrew Parish • Grand Etang, XI.1950, leg. N.L.H. Krauss (1 ♀
Lasioglossum (Dialictus) sanctivincenti (Ashmead), syntype female of Halictus sanctivincenti Ashmead A dorsal habitus B head, frontal view C lateral habitus. Images courtesy of the National Museum of Natural History, Smithsonian Institution. https://collections.nmnh.si.edu/search/ento/
The syntype series of L. sanctivincenti is divided between Grenada and St. Vincent (
♀. Saint Vincent, St. George Parish, 5–10.X.1991, leg. R.E. Woodruff, Malaise trap (FSCA).
SVG • Saint Vincent• St. George Parish • Rivulet Agr. Sta., 27–30-IX-1991, leg. R.E. Woodruff, Malaise trap (1 ♂); 5–10-X-1991, leg. R.E. Woodruff, Malaise trap (2 ♀ FSCA) • “24 // W. Indies / 99-331 // Dialictus not gemmatus det G.C. Eickwort” (1 ♀ NHMUK). One leg, both forewings and one hind wing missing. “69 // W. Indies 99-331 // Halictus gemmatus Smith Ashm // Dialictus not gemmatus det G.C. Eickwort” (NHMUK). In good condition, two submarginal cells in both wings (1 ♀ NHMUK) • St Vincent, Majorea, VIII.1972 (2 ♂ SEMC).
Halictus gemmatus:
Dialictus gemmatus:
Females of L. gemmeum are easily recognised by their orange-red metasoma and small size (~ 3.5 mm long). No other L. (Dialictus) in the Caribbean is known to have such a brightly coloured metasoma, although some L. (Habralictellus) do. Males can be distinguished from other SVG L. (Dialictus) by the elongate (1.5–2 MOD), pectinate setae on S5-S6. Other SVG L. (Dialictus) have short (1 MOD), simple setae on S5-S6, which contrast with plumose setae on preceding sternites.
Female (n = 5). Length 3.3–3.6 mm; head length 1.03–1.11 mm; head width 1.08–1.19 mm; intertegular distance 0.71–0.84 mm; wing length 1.38–1.60 mm.
Colouration. Head and mesosoma dull metallic blue-green to golden-green, except as follows. Labrum reddish brown. Mandible yellow-orange with brown base and red apex. Clypeal apex dark brown. Antenna dark brown, flagellum with ventral surface reddish brown. Pronotal lobe yellow-orange. Tegula amber. Wing membrane hyaline with dark setae, venation pale brown. Legs amber-brown. Metasomal terga orange.
Pubescence. Dull white. Relatively sparse erect setae throughout, without tomentum, except on gena near eye, pronotal dorsolateral angle and lobe. Metasomal T1 with fan virtually absent, no erect setae medially. T2 without apical fimbriae, T3–T4 with only sparse fine setae on apical impressed areas. Scopa well developed on hind leg and metasomal sterna.
Surface sculpture. Face imbricate, punctation moderately fine. Clypeal punctation moderately sparse (IS = 1–s PD), denser proximally (IS = 1 PD), surface smooth distally. Supraclypeal area with punctures moderately sparse (IS = 1–2 PD), weakly imbricate in centre. Lower paraocular area punctation dense (IS ≤ PD). Upper paraocular area and frons reticulate-punctate (IS < PD). Ocellocular area punctate (IS ≤ PD). Gena and postgena punctate-imbricate, sculpturing weak on postgena. Mesoscutum weakly imbricate, polished submedially; punctation moderately coarse, dense laterad of parapsidal lines, posterior portion (IS < PD), sparsest submedially (IS = 1–2 PD), mesoscutellum similar with submedial impunctate area (IS = 1–3 PD). Metanotum finely punctate. Preëpisternum finely reticulate rugulose. Hypoepimeral area finely punctate. Mesepisternum below scrobe punctate (IS ≤ d), polished. Metepisternum dorsal 1/3 lineolate, ventral portion reticulate-imbricate. Metapostnotum medially with irregular carinulae reaching 2/3 distance to imbricate posterior margin, dorsolateral slope imbricate. Propodeum posterior and lateral surfaces weakly imbricate. Metasomal terga polished, finely coriarious basally, weakly coriarious on apical impressed margin of T3; punctation sparse (IS = 2–3 PD) on basal half, indistinct, sparser on apical impressed areas, T1-T2 apical impressed areas nearly impunctate. Metasomal sterna coriarious and finely, sparsely punctate (IS = 2–4 PD).
Structure. Face relatively short (length/width ratio = 0.82 ± 0.01 SD). Eyes weakly convergent below (UOD/LOD ratio = 1.29 ± 0.19 SD). Clypeus 2/3 below suborbital tangent, apicolateral denticles low rounded knobs. Gena narrower than eye. Hypostomal carinae subparallel. Pronotal dorsolateral angle obtuse. Pronotal ridge rounded, interrupted by sulcus. Mesoscutum length/width ratio 0.82 (± 0.02 SD); mesoscutum/mesoscutellum length ratio 2.72 (± 0.2 SD); mesoscutellum/metanotum length ratio 1.75 (± 0.06 SD); metanotum/metapostnotum length ratio 0.64 (± 0.03 SD). Tegula ovoid. Submarginal cells two or three, veins 1r-sm, 2rs-m and 2m-cu distinctly weak. Distal hamuli arranged 2-1-2. Inner metatibial spur pectinate, with two or three branches not including apex of rachis, proximal branch much longer than width of rachis. Metapostnotum narrowly rounded onto posterior propodeal surface. Propodeum with lateral carina reaching 1/2 distance dorsal margin; oblique carina indistinct. Metasoma ovoid, T2–T4 impressed areas medially ~ 1/2 longitudinal length of basal area.
Male (n = 3). Length 3.3–3.5 mm; head length 1.00–1.08 mm; head width 1.00–1.11 mm; intertegular distance 0.67–0.79 mm. Similar to female with usual sex-associated modifications.
Colouration. Head and mesosoma green to golden green. Clypeal apex reddish brown. Labrum reddish brown. Mandible brown, orange apically. Flagellum reddish brown, sometimes orange ventrally. Pronotal lobe reddish brown to orange. Tegula orange. Wing membrane hyaline, veins brown to dark brown. Legs reddish brown with femur-tibia joints, base and apex of tibiae, and tarsi orange. Metasoma reddish brown.
Pubescence. Body sparse pilosity, dull white to faintly yellowish. Tomentum moderately dense on lower paraocular area, sparse on clypeus, dense on pronotal lobe. Mesoscutal pilosity thin. Sternal pilosity short (1.0–1.5 OD), densely plumose, dense, erect. Wing setae dark, short, sparse.
Surface sculpture. Clypeal punctures dense (IS ≤ 1 PD), interspaces polished. Supraclypeal punctures sparse (I = 1–2 PD), interspaces polished. Paraocular area punctures dense (IS ≤ 1 PD), interspaces shiny. Frons punctate-reticulate. Gena punctate-imbricate, postgena sculpture punctate-imbricate. Tegula mostly impunctate. Mesoscutal punctation sparse (IS = 1–3 PD), becoming dense marginally (IS = 1–1.5 PD), interspaces shiny. Mesoscutellar punctation sparse (IS = 1–2 PD). Metanotum punctate. Metapostnotum with incomplete carinulae, margin shiny to weakly imbricate. Pre-episternum sculpture punctate. Hypoepimeral area distinctly punctate IS ≤ 1 PD), interspaces polished. Mesepisternum distinctly punctate (IS ≤ 1 PD), interspaces shiny. Metepisternum lineate dorsally, weakly rugulose ventrally. Propodeal lateral face weakly imbricate-punctate, dorsolateral slope punctate. Propodeal posterior face sculpture polished-punctate. T1 anterior face polished. T1 dorsal surface sparse (IS = 2–6 PD), interspaces shiny. T2 disc punctures sparse (IS = 1–2.5 PD), failing well before premarginal line, interspaces shiny, apical impressed area impunctate, interspaces shiny.
Structure. Face length/width ratio 0.84 (± 0.03 SD). F1: pedicel length ratio 0.77–1.00. F2:F1 length ratio 1.76–1.89. Gena narrower than eye. Hypostomal carinae parallel. Pronotal angle obtuse. Mesoscutum length/width ratio 0.0.8 (± 0.02 SD); mesoscutum/mesoscutellum length ratio 2.51 (± 0.03 SD); mesoscutellum/metanotum length ratio 2.04 (± 0.25 SD); metanotum/metapostnotum length ratio 0.59 (± 0.07 SD). Propodeum lateral carina nearly halfway to dorsal margin; oblique carina absent. Tegula ovoid. Forewing with two or three submarginal cells. Metatibial spurs ciliate. Metasoma slender, parallel sided.
The specific epithet is a Latin adjective in the nominal singular meaning glittering.
Halictus auratus
Halictus auratus:
Habralictellus auratus:
Lasioglossum (Dialictus) auratum:
Lasioglossum (Habralictellus) auratum:
Lasioglossum auratum is the type species of Habralictellus, a genus group that has fluctuated between treatments as a genus (
Lasioglossum (Dialictus) minutum (Fabricius), syntype male of Hylaeus minutus Fabricius A dorsal habitus B head, oblique frontal-ventral view C lateral habitus. Images courtesy of the Natural History Museum of Denmark. Photographs by Mikkel Høegh Post. http://www.daim.snm.ku.dk/search-in-types
1 | Head and mesosoma brilliant metallic golden-green (Fig. |
L. auratum |
– | Head and mesosoma dull metallic golden-green to blue; mesoscutum imbricate to weakly polished with relatively coarse and distinct punctation; subgenus Dialictus | 2 |
2 | Metasoma dark metallic blue (Figs |
L. cyaneum |
– | Metasoma brown to orange; wings relatively pale | 3 |
3 | Female | 4 |
– | Male | 6 |
4 | Metasoma orange-red (Fig. |
L. gemmeum |
– | Metasoma brown; head longer; tegula reddish brown to dark brown | 5 |
5 | Head and mesosoma blue (Figs |
L. plumbeum |
– | Head and mesosoma golden green (Figs |
L. sanctivincenti |
6 | Mesoscutum disc shiny, punctation sparse (Fig. |
L. gemmeum |
– | Mesoscutum disc duller, punctation denser (Figs |
7 |
7 | Head and mesosoma blue; face relatively long (length/width ratio = 0.86) | L. plumbeum |
– | Head and mesosoma golden green; face relatively short (length/width ratio = 0.82) | L. sanctivincenti |
Hylaeus minutus Fabricius 1798: 272. Americae insulus. Syntype ♂ (Natural History Museum of Denmark).
Prosopis minuta: Dalla Torre (1896: 27) catalogue; Fabricius (1804: 295) redescription.
Dialictus (Chloralictus) minutus: Moure (1960a: 101) redescription, taxonomic status, distribution; Moure (1960b: 76) redescription, taxonomic status.
Lasioglossum (Evylaeus) minutum:
Dialictus minutus:
The distribution and identity of L. minutum remains in doubt. Fabricius (1798) did not specify the number of specimens examined, but a single male type is known. Moure (1960a) examined this type of Hylaeus minutus Fabricius and transferred it to Dialictus (Chloralictus). The type locality is “Americae insulus”, clarified subsequently to be “Americae meridionalis insulus” (Fabricius 1804). Moure (1960b) thought it was from St. Vincent.
The nomenclature of L. minutum is somewhat confusing as discussed by earlier authors (
Based on the species richness of the relatively well-studied islands of Dominica (26 spp.) to the north and Saint Vincent and the Grenadines (33 spp.) to the south (
Our sincere appreciation is given to the various collections managers and curators that have supported this research through the generous preparation of loans. Jerome Rozen (