Lasioglossum (Dialictus) nanotegula Landaverde-González & Husemann, 2023

Landaverde-González, Patricia, Gardner, Joel, Moo-Valle, Humberto, Quezada-Euán, José Javier G., Ayala, Ricardo & Husemann, Martin, 2023, Seven new species of Lasioglossum (Dialictus) Robertson, 1902 (Hymenoptera: Halictidae: Halictini) from the Yucatán Peninsula, Mexico, European Journal of Taxonomy 862 (1), pp. 1-65 : 45-50

Lasioglossum (Dialictus) nanotegula Landaverde-González & Husemann sp. nov.

urn:lsid:zoobank.org:act:907458CF-52CC-464C-A761-66B9373D5153

Figs 6H , 20–21 , 25B , 26B , 27B , 34B

Diagnosis

Females of L. (D.) nanotegula sp. nov. can be recognised by the diagnostic combination of tegula small, ovoid (tegula width/ITS <0.20), and impunctate; frons punctures much finer and denser than those of lower paraocular area; head broader than long (length/width0.91–0.95); mesoscutum moderately sparsely punctate between parapsidal lines (i = 1–3 pd), becoming dense but not crowded laterad of parapsidal lines (i ≤ 1 pd); metapostnotum shiny to weakly tessellate with strong coarse rugae reaching posterior margin; and T1–T3 apical impressed areas evenly covered with fine sparse punctures (i = 1–3 pd) with short simple setae arising from them (except absent on T1 medially). Males can be recognised by the same characters (however, the single male available for study is missing the metasoma, so metasomabased diagnostic characters are uncertain); in addition, males have the paraocular area and lower frons with dense appressed tomentum.

Differential diagnosis

Females of L. (D.) nanotegula sp. nov. are most similar to those of L. (D.) milpa sp. nov. and L. (D.) ameshoferi sp. nov. For comparison with Lasioglossum (D.) ameshoferi see above in L. (D.) ameshoferi

differential diagnosis; however, the male of that species is unknown. For comparison with L. (D.) milpa see above in L. (D.) milpa differential diagnosis.

Etymology

The specific epithet ‘ nanotegula ’ is a combination of the Latin nouns ‘ nanus ’ (‘dwarf’) and ‘ tegula ’ (‘roof tile’, literally ‘covering instrument’, now applied to the sclerite covering the wing base). It refers to the small size of the tegula.

Type material

Holotype MEXICO – Yucatán • ♀; Mérida , 15 km S of University of Yucatán; [20.83° N, 89.62° W]; 7 Apr. 1997; R.W. Brooks leg.; ex Piscidia piscipula ; SEMC SM0105925 .

Paratypes GUATEMALA – Huehuetenango • 1 ♀; Jacaltenango, San Andrés ; 15.7167° N, 91.7455° W; elev. 1027 m; 28 Feb. 2010; Miguel Cigarroa leg.; ECOAB.43341 • 1 ♀; La Democracia, Camojaíto ; 15.616° N, 91.8727° W; elev. 940 m; 1 Mar. 2010; Daniel Sánchez leg.; ECOAB.43336 • 1 ♀; San Antonio Huista, Pinalito ; 15.6653° N, 91.8618° W; elev. 963 m; 2 Mar. 2010; Jaime Florez leg.; ECOAB.43339 .

MEXICO – Chiapas • 1 ♀; Arriaga, Ej. Adolfo López Mateos; 16.3463° N, 93.9741° W; elev. 367.5 m; 17 Jul. 2009; Carlos Balboa, Miguel Guzmán and Miguel Cigarroa leg.; ECOAB.53487 • 1 ♀; same collection data as for preceding; 17 Nov. 2009; ECOAB.53350 • 1 ♀; Arriaga, Paraje, Poza Verde ; 16.3428° N, 93.952° W; elev. 465.5 m; 14 Mar. 2009; Carlos Balboa, Miguel Guzmán and Miguel Cigarroa leg.; ECOAB.53314 • 1 ♀; same collection data as for preceding; 15 Jul. 2009; ECOAB.53483 • 2 ♀♀; La Trinitaria, Carretera 190; 16.0424° N, 92.0179° W; elev. 1041 m; 15 Feb. 2014; Philippe Sagot leg.; ECOAB.53398, ECOAB.53399 • 1 ♀; Mapastepec , El Unión Los Olivos; 15.3083° N, 92.4738° W; elev. 315 m; 1 Apr. 2005; M. Rincón, Ricardo Ayala Barajas, R. Vandame and Miguel Guzmán leg.; ECOAB.43760 • 1 ♀; Ocosingo , El Rosario; 16.8859° N, 92.2742° W; elev. 1118 m; 11 Feb. 2010; Philippe Sagot leg.; ECOAB.43281 • 2 ♀♀; Ocosingo, Sibaca ; 16.9447° N, 92.1839° W; elev. 1107 m; 12 Apr. 2010; Carlos Balboa leg.; ECOAB.43271, ECOAB.43331 • 1 ♀; San Juan Cancuc, Tzuluwitz ; 16.894° N, 92.4019° W; elev. 1270 m; 6 Apr. 2010; Philippe Sagot leg.; ECOAB.43325 . – Quintana Roo • 1 ♀; 12 km NW of Reforma ; [18.89° N, 88.65° W]; 14 Oct. 1986; Charles D. Michener leg.; SEMC . – Yucatán • 1 ♂; same collection data as for holotype; SEMC SM0105924 (photographed) • 1 ♀; Tah Dziú ; [20°10′06.9″ N, 88°55′36.2″ W]; 7 Jun. 2011; Quezada-Euán and Moo-Valle leg.; original label 237; ZMH 842031 • 2 ♀♀; 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 – Jalisco • 1 ♀; Chamela ; [19.5° N, 105.04° W]; 26 Sep. 1985; R.J. McGinley leg.; USNM • 1 ♀; same collection data as for preceding; 30 Sep. 1985; USNM • 2 ♀♀; Guadalajara ; [20.65° N, 103.35° W]; J.C. Crawford leg.; USNM • 1 ♀; Mascota ; [20.53° N, 104.79° W]; 17 Jul. 1989; R.J. McGinley leg.; USNM . – Yucatán • 1 ♂; Tah Dziú ; 6 Jun. 2011; Quezada-Euán and Moo-Valle leg.; original label 452b; ZMH 839503 • 1 ♀; Muna ; [20°28′15.7″ N, 89°46′53.5″ W]; 22 Jul. 2011; Quezada-Euán and Moo-Valle leg.; original label 570; ZMH 842054 • 1 ♀; Tixmehuac ; [20°15′52.4″ N, 89°08′58.1″ W]; 15 Jun. 2011; Quezada-Euán and Moo-Valle leg.; original label 410; ZMH 842034 • 1 ♀; Tixcuytun ; [20°12′21.80″ N, 89°09′17.50″ W]; 7 Jun. 2011; Quezada-Euán and Moo-Valle leg.; original label 488b; ZMH 842036 • 1 ♂; Xaya , [20°16′51.70″ N, 89°11′28.70″ W], 5 Aug. 2011; Quezada-Euán and Moo-Valle leg.; original label 621c; ZMH 839508 • 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 842037 • 1 ♀; Muna ; [20°28′15.7″ N, 89°46′53.5″ W]; 22 Jul. 2011; Quezada-Euán and Moo-Valle leg.; original label 569a; ZMH 842068 • 1 ♀; Yaxcopil ; [20°4′4.10″ N, 88°54′23.80″ W]; 1 Aug. 2011; QuezadaEuán and Moo-Valle leg.; original label 605b; ZMH 842069 • 1 ♀; Alfonso Caso ; [20°05′02.5″ N, 89°09′39.3″ W]; 25 Oct. 2011; Quezada-Euán and Moo-Valle leg.; original label 92; ZMH 842066 .

Floral records

FABACEAE Juss. : Piscidia L.: P. piscipula (L.) Sarg. • SOLANACEAE Adans. : Capsicum L.: C. chinense Jacq.

DNA barcodes

Seventeen sequences available (BOLD process IDs: LDSPS040-15 to LDSPS051-15, LDSPS096-15, LDSPS097-15, LDSPS100-15 to LDSPS102-15). These sequences are highly variable (maximum intraspecific p-distance 1.3%; minimum interspecific distance, to L. aureoviride sp. nov., 3.96%). The other sequences not from Yucatán are much less variable, with a clear barcode gap (maximum intraspecific p-distance 0.2%; minimum interspecific distance, to L. nanotegula sp. nov., 4.4%). This species is a member of the informal L. comulum species group and corresponds to mOTU 4 in Landaverde-González et al. (2017a).

Description

Female (holotype)

MEASUREMENTS. Length 4.45 mm; head length 1.21 mm; head width 1.33 mm; fore wing length 2.93 mm. Six female paratypes measured: length 4.25–4.46 mm; head length 1.15–1.21 mm; head width 1.21– 1.33 mm; fore wing length 2.91–2.94 mm.

COLOUR. Head and mesosoma metallic blue-green to olive green; clypeus apical half black; supraclypeal area with golden reflection; scape and pedicel black, F1–F10 black, F8–F10 becoming brown ventrally; wing membrane subhyaline, subcosta dark brown, venation and pterostigma otherwise light brown; legs dark brown with distitarsi light brown; metasoma dark brown with rims of terga and sterna lighter reddish 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 (2 OD); T1 with with dense complete setose fan; T2–T3 with small basolateral patches of appressed tomentum covering less than half length of segment laterally; disc of T4 with sparse appressed tomentum throughout; T1–T5 evenly covered with dense, short, simple setae, about half as long on T1–T2, becoming long and plumose laterally (1–2.5 OD); tibia and tarsal segments with plumose light-yellow setae.

SURFACE SCULPTURE. Clypeus shiny and densely punctate (i ≤ 1 pd); supraclypeal area shiny and moderately sparsely punctate (i = 1–2 pd); paraocular area and antennocular area shiny and very densely punctate (i <0.5 pd); upper paraocular area and frons with fine crowded punctures (i = 0 pd); gena and postgena shiny; mesoscutum moderately sparsely punctate between parapsidal lines (i = 1–3 pd), becoming dense and crowded laterad of parapsidal lines (i ≤ 1 pd); mesepisternum imbricate and densely punctate (i ≤ 1 pd); metapostnotum shiny to weakly tessellate, with strong coarse rugae reaching posterior margin; propodeum with lateral surface and posterior surface weakly tessellate; T1– T3 minutely, sparsely punctate (i = 1–3 pd); T1 apical impressed area impunctate medially.

STRUCTURE. Head wide (length/width ratio = 0.91–0.95; holotype = 0.91); eyes weakly convergent below (UOD/LOD ratio = 1.23–1.28; holotype = 1.23); clypeus ⁴/5 below suborbital tangent; antennal sockets close (IAD/AOD <0.52); frontal line ending> 2.5 OD below median ocellus; head broader than long (length/width 0.91–0.95); gena narrower than eye; inner metatibial spur with three teeth; tegula small, ovoid, not produced mesally (tegula width/ITS <0.215); scutellum length 0.28; metapostnotum length 0.22, metapostnotum elongate (MMR ratio = 1.27), posterior margin rounded onto posterior surface; propodeum with oblique carina straight and lateral carina not reaching margin of dorsal surface.

Male

MEASUREMENTS. Length 3.58 mm; head length 1.05 mm; head width 1.09 mm; fore wing length 2.57 mm.

COLOURATION. Head and mesosoma metallic blue-green; scape and pedicel dark brown; F1–F10 dark brown dorsally, light brown ventrally; legs dark brown with tibial bases, apices, and tarsi light brown.

PUBESCENCE. Dull white. Head and mesosoma with abundant plumose short setae (0.5–2 OD); paraocular area and lower frons with dense appressed tomentum; clypeus, supraclypeal area, and gena with sparse appressed tomentum; propodeum with abundant plumose setae on lateral and posterior surfaces (1–2 OD); S3–S5 pubescence short (1–2 OD), suberect, and weakly plumose, appearing simple at <40 × magnification; tibia and tarsal segments with plumose light-yellow setae.

SURFACE SCULPTURE. Clypeus shiny and sparsely punctate (i = 1–3 pd); supraclypeal area shiny and moderately sparsely punctate (i = 1–2 pd); lower paraocular area and antennocular area shiny and densely punctate (i <1 pd); upper paraocular area and frons shiny with crowded punctures (i = 0 pd); ocellocular area shiny and densely punctate (i ≤ 1 pd); gena and postgena weakly imbricate-rugulose, mostly shiny; mesoscutum shiny and sparsely punctate between parapsidal lines (i = 1–3 pd), becoming moderately denser laterad of parapsidal lines (i ≤ 1.5 pd); mesepisternum shiny and densely punctate (i <1 pd); metapostnotum shiny with strong or somewhat finer rugae not reaching onto propodeum dorsolateral slope except at base; propodeum with lateral surface and posterior surface shiny and moderately densely punctate (i = 1–2 pd) and with oblique carina absent.

STRUCTURE. Head wide (length/width ratio = 0.97–0.99); eyes weakly convergent below (UOD/LOD ratio = 1.55); clypeus⁴/5 below suborbital tangent; antennal sockets close (IAD/AOD <1.07); frontal line ending 2.5 OD below median ocellus; gena narrower than eye; scutellum length 0.22; metapostnotum length 0.17, metapostnotum elongate (MMR ratio = 1.29); genitalia not examined.

Distribution

Yucatán Peninsula, northern Chiapas, and northern Guatemala, possibly also the Pacific coast to Jalisco. The five outlier Jalisco specimens seem morphologically indistinguishable from this species, but until additional records are found to fill the distribution gap, the possibility that they are a cryptic species must be considered and they are therefore excluded from the paratype series.

Remarks

Uncommon. This species is a member of the informal L. comulum species group and corresponds to mOTU 4 in Landaverde-González et al. (2017a).

Figures

Fig. 6. Images of tegula form and punctation in species of Lasioglossum (Dialictus) Robertson, 1902. A. L. (Dialictus) yucatanense Landaverde-González sp. nov. B. L. (Dialictus) paxtoni Landaverde- González sp. nov. C. Specimen of the Lasioglossum stictaspis species complex. D. L. (Dialictus) ameshoferi Landaverde-González sp. nov. E. L. (Dialictus) aureoviride Landaverde-González & Husemann sp. nov. F. L. (Dialictus) paralepidii Gardner sp. nov. G. L. (Dialictus) milpa Landaverde- González sp. nov. H. L. (Dialictus) nanotegula Landaverde-González & Husemann sp. nov.

Fig. 20. Lasioglossum (Dialictus) nanotegula Landaverde-González & Husemann sp. nov., holotype, ♀ (SM0105925). A. Lateral habitus. B. Dorsal habitus. C. Face.

Fig. 21. L. (Dialictus) nanotegula Landaverde-González & Husemann sp. nov., ♂ (SM0105924). A. Lateral habitus. B. Dorsal habitus. C. Face.

Fig. 25. Face. A. Lasioglossum (Dialictus) ameshoferi Landaverde-González sp. nov., ♀, punctures very coarse, with frons punctures about as large and dense as in lower paraocular area. B. L. (D.) milpa Landaverde-González sp. nov., ♀, punctures finer, with frons punctures smaller and denser than in lower paraocular area, head about as long as broad. C. L. (D.) nanotegula Landaverde-González & Husemann sp. nov., ♀, punctures finer, with frons punctures smaller and denser than in lower paraocular area, head broader than long.

Fig. 26. Mesoscutum punctation. A. Lasioglossum (Dialictus) ameshoferi Landaverde-González sp. nov., ♀, dense (i <1 pd). B. L. (D.) nanotegula Landaverde-González & Husemann sp. nov., ♀, sparse (i = 1–3 pd).

Fig. 27. Mesoscutum punctation lateral of parapsidal line.A. Lasioglossum (Dialictus)milpa Landaverde- González sp. nov.; sparse (i = 1 pd). B. L. (D.) nanotegula Landaverde-González & Husemann sp. nov.; dense (i <1.0 pd).

Fig. 34. Propodeum. A. Lasioglossum (Dialictus) exiguum (Smith, 1879), ♂, with metapostnotum rugae not reaching posterior margin and dorsolateral slope smooth (arrow). B. L. (D.) nanotegula Landaverde- González & Husemann sp. nov., ♂, with metapostnotum rugae reaching posterior margin and extending onto dorsolateral slope at base (arrow). C. L. (D.) ameshoferi Landaverde-González sp. nov., ♂, with metapostnotum rugae reaching posterior margin and covering dorsolateral slope (arrow).