Seven new species of Lasioglossum (Dialictus) Robertson, 1902 (Hymenoptera: Halictidae: Halictini) from the Yucatán Peninsula, Mexico Author Landaverde-González, Patricia CFEE1568-9AD9-4531-885D-EBF3F68ABB43 General Zoology, Institute for Biology, Martin-Luther University Halle-Wittenberg, Hoher Weg 8, 06120 Halle (Saale), Germany. patricia.landaverde@zoologie.uni-halle.de Author Gardner, Joel AA15FE6E-921A-46D6-BC67-88E067F283D9 Department of Entomology, University of Manitoba, 12 Dafoe Rd., Winnipeg, Manitoba, R 3 T 2 N 2, Canada. clickbeetle3364@gmail.com Author Moo-Valle, Humberto 35656D9E-491C-4C34-8CAD-069E4B9F0E9B Departamento de Apicultura Tropical, Campus Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Mérida, Mexico. moovalle@correo.uady.mx Author Quezada-Euán, José Javier G. BD9DBC7E-AD59-47BA-BA72-4A881A31E320 Departamento de Apicultura Tropical, Campus Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Mérida, Mexico. javier.quezada@correo.uady.mx Author Ayala, Ricardo B1CFBA3B-C28B-40C5-B674-CBC8DB69418C Estación de Biología Chamela, Instituto de Biología, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 21, San Patricio Jalisco, 48980, Mexico. rayala@ib.unam.mx Author Husemann, Martin D31A05CA-DCD8-4CFB-A9D0-E9F070EC4707 Centrum für Naturkunde, University of Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany. martin.husemann@uni-hamburg.de text European Journal of Taxonomy 2023 2023-03-22 862 1 1 65 http://dx.doi.org/10.5852/ejt.2023.862.2079 journal article 264116 10.5852/ejt.2023.862.2079 957e3c13-6dd3-4b13-9576-9f013a4990bc 2118-9773 7767855 5D38246E-B144-434C-A2FE-C303381B0CD7 Lasioglossum ( Dialictus ) milpa Landaverde-González sp. nov. urn:lsid:zoobank.org: act: 6D61F2D7-BF99-4B3E-8560-01405B0F3977 Figs 6G , 19 , 25C , 27A Diagnosis Females of L. ( D. ) milpa sp. nov. can be recognised by the diagnostic combination of tegula small, ovoid, not produced mesally (tegula width/ITS <0.20), and impunctate; frons punctures much smaller and denser than those of lower paraocular area; mesoscutum sparsely punctate between parapsidal lines (i = 1.5–3 pd), becoming moderately dense but not crowded laterad of parapsidal lines (i = 1 pd); metapostnotum dull, imbricate with shallow anastomosing rugae reaching posterior margin or nearly so; and head about as long as broad (length/width 0.95–0.99). The male is unknown. Differential diagnosis Females of Lasioglossum ( D. ) milpa sp. nov. are most similar to those of L. ( D. ) ameshoferi sp. nov. , L. ( D. ) nanotegula sp. nov. , and L . ( D. ) aureoviride sp. nov. Females of L. ameshoferi also have the frons punctures as large and dense as those in the lower paraocular area and the mesoscutum much more coarsely and densely punctate laterad of the parapsidal lines (i = 0 pd). Females of L. ameshoferi and L. nanotegula have the metapostnotum shiny with strong and coarse rugae and the propodeum with its oblique carina U-shaped and extending onto the dorsolateral slope. Females of L. aureoviride have the tegula enlarged (reaching posterior margin in dorsal view), with the inner posterior margin straight. Etymology The specific epithet ‘ milpa ’ is a noun in apposition that refers to the traditional agriculture that is mainly found in the region and apparently beneficial for the different species of Lasioglossum ( Dialictus ) found there ( Landaverde-González et al . 2017b ). Type material Holotype MEXICO – Campeche • ♀ ; Hopelchén ; 19.41° N , 89.35° W ; elev. 130 m ; 27 Jan. 2016 ; Eric Vides leg.; ECOAB .82909. Paratypes MEXICO – Chiapas • 1 ♀ ; Ocosingo, El Rosario ; 16.8859° N , 92.2742° W ; elev. 1118 m ; 11 Feb. 2010 ; Jorge Mérida leg.; ECOAB .43291 . – Yucatán • 1 ♀ ; Tixcacaltuyub ; [ 20.4175° N , 88.931° W ]; 22 Jun . 2011; Quezada-Euán and Moo-Valle leg.; ZMH 839502 • 1 ♀ ; Uxmal Ruins , 16 km SW of Muna ; [ 20.36° N , 89.77° W ]; 14 Feb. 1987 ; Charles D. Michener leg.; SEMC . Other material examined MEXICO – Yucatán • 1 ♀ ; Tixcacaltuyub ; [ 20.4175° N , 88.931° W ]; 22 Jun. 2011 ; Quezada-Euán and Moo-Valle leg.; ZMH 839505 • 2 ♀♀ ; Yaxcopil ; [ 20°4′4.10″ N , 88°54′23.80″ W ]; 25 Oct. 2011 ; Quezada-Euán and Moo-Valle leg.; original labels 602a, 602b; ZMH 81035 , 81036 • 2 ♀♀ ; same collection data as preceding; original labels 604a1, 604a2; ZMH 81037 , 81038 • 1 ♀ ; Tah Dziú ; [ 20°10′06.9″ N , 88°55′36.2″ W ]; 6 Jun. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 240a2; ZMH 839504 • 1 ♀ ; Alfonso Caso ; [ 20°05′02.5″ N , 89°09′39.3″ W ]; 25 Oct. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 84; ZMH 842058 • 1 ♀ ; Alfonso Caso ; [ 20°05′02.5″ N , 89°09′39.3″ W ]; 25 Oct. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 85; ZMH 842059 • 1 ♀ ; Moctezuma ; [ 21°24′46.2″ N , 87°42′05.7″ W ]; 30 May 2011 ; Quezada-Euán and Moo-Valle leg.; original label 159; ZMH 842028 • 1 ♀ ; Tah Dziú ; [ 20°10′06.9″ N , 88°55′36.2″ W ]; 7 Jun. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 238; ZMH 842032 • 1 ♀ ; Tixcacaltuyub ; 20°25′03.1″ N , 88°55′51.5″ W ; 22 Jun. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 503d; ZMH 842061 • 1 ♀ ; Santa María ; [ 20°23′32.5″ N , 88°55′14.6″ W ]; 26 Jul. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 587b; ZMH 842063 • 1 ♀ ; Santa María ; 20°23′32.5″ N , 88°55′14.6″ W ; 26 Jul. 2011 ; Quezada-Euán and MooValle leg.; original label 588; ZMH 842064 • 1 ♀ ; Tixcuytun ; [ 20°12′21.80″ N , 89°09′17.50″ W ]; 7 Jun. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 493; ZMH 842060 • 1 ♀ ; Muna ; 20°28′15.7″ N , 89°46′53.5″ W ; 22 Jul. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 570c; ZMH 842062 • 1 ♀ ; Nenela ; [ 20°20′10.90″ N , 89°1′19.20″ W ]; 10 May 2011 ; Quezada-Euán and Moo-Valle leg.; original label 40; UADY • 1 ♀ ; Timul ; 20°18′56.1″ N , 88°55′55.9″ W ; 9 Jun. 2011 ; Quezada-Euán and Moo-Valle leg.; original label 301; UADY . Floral records SOLANACEAE Adans. : Capsicum L.: C. chinense Jacq. DNA barcodes Twenty-eight sequences available (BOLD process IDs: LDSPS077-15 to LDSPS095-15, LDSPS098-15, LDSPS099-15, LDSPS103-15 to LDSPS109-15). These sequences are extremely variable, and therefore poorly distinguished from those of other species (maximum intraspecific p-distance 2.45%; minimum interspecific p-distance (to L. aureoviride sp. nov. ) 4.32%). This group of sequences is very tentatively attributed to L. milpa sp. nov. based on their similarity to the L . sp. mex8 sequence (unfortunately the original specimen to be designated as holotype was destroyed), an undescribed species which is most morphologically similar to L. milpa . However, it is possible that more cryptic species exists. Description Female ( holotype ) MEASUREMENTS. Length 4.13 mm ; head length 1.24 mm ; head width 1.3 mm ; fore wing length 2.93 mm . Eight female paratypes measured: length 4.13–5.10 mm ; head length 1.17–1.24 mm ; head width 1.22– 1.3 mm ; fore wing length 2.78–2.93 mm . COLOUR. Head and mesosoma blue-green to olive green; clypeus apical half black; scape and pedicel black; F1–F10 black dorsally, brown ventrally; tegula reddish brown; wing membrane subhyaline, venation and pterostigma brown; legs dark brown; metasoma black with rims of terga and sterna dark brown. PUBESCENCE. Dull white; head and mesosoma with abundant long setae (1–2.5 OD); lower paraocular area and gena with sparse subappressed tomentum; propodeum with abundant plumose setae on lateral and posterior surfaces (1.5–2.5 OD); mesepisternum with dense plumose setae (1–1.5 OD); T1 with dense complete setose fan; T1 shiny with sparse, short, simple setae medially; T2–T4 evenly covered with dense, short, simple setae, about half as long on T2 and absent on apical impressed area medially; T2–T3 with small basolateral patches of appressed tomentum covering less than half length of segment laterally; T4 with sparse tomentum in basal half, tibia and tarsal segments with plumose light-yellow setae. Fig. 19. Lasioglossum ( Dialictus ) milpa Landaverde-González sp. nov. , holotype, ♀ (ECOAB.82909). A . Lateral habitus. B . Dorsal habitus. C . Face. SURFACE SCULPTURE. Clypeus shiny and densely punctate (i ≤ 1 pd); supraclypeal area shiny and moderately sparsely punctate (i = 1–2 pd); lower paraocular area shiny and densely punctate (i <1 pd); antennocular area imbricate and densely punctate (i ≤ 1 pd); upper paraocular area and frons shiny with crowded punctures (i = 0 pd); ocellocular area shiny and moderately densely punctate (i = 1–2 pd); punctures of upper half of face distinctly smaller and denser than punctures of lower half; gena and postgena lineate; mesoscutum between parapsidal lines sparsely punctate (i = 1.5–3 pd), becoming moderately dense laterad of parapsidal lines (i = 1 pd); metapostnotum dull, imbricate with shallow anastomosing rugae reaching posterior margin or nearly so; mesepisternum slightly sparsely punctate (i ≤ 1–1.5d); metepisternum finely rugulose; propodeum posterior surface tessellate; discs of T1–T2 very finely, minutely, sparsely punctate (i = 1–3 pd); T2 apical impressed area very minutely, sparsely punctate laterally (i = 2–4 pd). STRUCTURE. Head wide (length/width ratio = 0.94–0.99; holotype = 0.95); eyes weakly convergent below (UOD/LOD ratio = 1.14–1.30; holotype = 1.27); clypeus ⁴/5 below suborbital tangent; antennal sockets close (IAD/AOD <0.55); frontal line ending <2 OD below median ocellus; head about as long as broad (length/width 0.94–0.99); gena wider than eye; tegula small, ovoid, not produced mesally; inner metatibial spur pectinate, with 3–4 teeth; scutellum length 0.25; metapostnotum length 0.2, metapostnotum elongate (MMR ratio = 1.25), posterior margin sharply angled onto posterior surface; propodeum with lateral carina not reaching margin of dorsal surface. Male Unknown. Distribution Yucatán Peninsula and northern Chiapas . Remarks This species is a member of the informal L. comulum species group and corresponds to mOTU 6 in Landaverde-González et al . (2017a) .