Mexalictus (Georgealictus) sheffieldi Dumesh, 2013

DUMESH, SHEILA, 2013, <p> <strong> Revision of the rare Mesoamerican bee genus <em> Mexalictus </ em> (Hymenoptera: Halictidae) with the description of </ strong> <br /> <strong> 21 new species </ strong> </ p>, Zootaxa 3708 (1), pp. 1-80 : 72-73

Mexalictus (Georgealictus) sheffieldi Dumesh , new species

( Figs. 180–181 )

Holotype. Female. GUATEMALA, Quiche, 2kms S Chichicastenango Rio Tesoro , 11 September 1987, M. Sharkey [ CNC].

Diagnosis. This species can be distinguished from others by the following combination: head wider than long, depressed around antennal sockets; clypeus shorter than supraclypeal area; supraclypeal area apically widened with punctures dense laterally; S6 covered in dense pale hairs.

Description. Female (Holotype): Body length 9.0– 9.2mm, wing length 7.8–8.0mm, head width 2.15mm. Head: round, L:W = 0.96:1, depressed around area of antennal sockets. (1) Labrum and mandible: with subrectangular basal area, flattened basal elevation, narrow triangular distal process. (2) Clypeus: length 0.83X length of supraclypeal area, 4/5 of length below lower ocular tangent, convex in lateral view, not as protuberant supraclypeal area; punctures separated by 1pd basally, coarse and sparse apically (2pd). (3) Supraclypeal area: dull, slightly shiny directly below antennal sockets; strongly convex in lateral view; apically widened, width 1.15X length; punctures closer laterally (1pd) becoming sparse centrally (>3pd). (4) Lower paraocular area: mostly dull becoming shiny apicolaterally and towards paraocular lobe; punctation becoming less crowded below antennae, especially towards supraclypeal area (2pd), very finely punctate laterad of paraocular lobe towards inner margin of compound eyes, punctures separated by 2–3pd. (5) Frontal area: punctures dense and crowded, separated by 0.25pd at most; frontal line carinate only between antennae, from basal third of supraclypeal area to 3MOD from median ocellus, with a somewhat obscure line reaching median ocellus. (6) Vertexal area: shiny; OOD = 2.0MOD, IOD = 1.6MOD, OVD = 1.1MOD; punctures obscure medially around ocelli, becoming coarse and dense laterally (<1pd). (7) Genal and hypostomal areas: genal area as wide as compound eye in lateral view, shiny with fine punctures separated by 1pd above, becoming sparser below (2–3pd); hypostomal area shiny, bare, and nearly impunctate. (8) Antenna: scape reaching past median ocellus, pedicel slightly longer than wide, F2 shorter than F1, flagellomeres slightly increasing in length from F2–F10, F2–F5 wider than long, F6–F9 quadrate, F10 longer than wide. Mesosoma: (9) Pronotum: smooth, impunctate, shinier laterally; pronotal lobe pubescent, bearing pale branched hairs. (10) Mesoscutum: dull, appearing granular, especially along margins and median line; densely punctate, punctures separated by 1–2pd in central disc, becoming more crowded basally and laterally past parapsidal line. (11) Mesoscutellum: dull with central disc shiny, medially raised basally, without a medial depression; punctures finer than on mesoscutum, separated by 1pd in central disc, becoming dense towards margins with several larger punctures sparsely among them (>5pd). (12) Metanotum: somewhat shiny, with shallow sparse punctures, separated by>2pd; with short, whitish-yellow hairs basally. (13) Mesopleuron: granular and sparsely punctate, punctures separated by 4–6pd; pre-episternum weakly granular anteriorly, punctures deep and crowded above, otherwise as on mesopleuron; hypoepimeral area and central episternum mostly impunctate. (14) Metapleuron: transversely striate basally, striation weakened, otherwise weakly shiny and impunctate. (15) Metapostnotum and propodeum: metapostnotum dorsally bare and weakly granular, length 0.90X length of mesoscutellum, posteriorly rounded, dorsal striation present basally, normal throughout, slightly longer medially, extending to apical; propodeum imbricate, strongly sloping posteriorly. (16) Wings: marginal cell tinted dark brown, venation dark brown on marginal and basal veins; 1 st recurrent vein meeting 2 nd submarginal cell 1–2 vein widths basad of 2 nd transcubital vein. (17) Tegula: brown, anteriorly dull becoming shiny posteriorly, anteriorly punctate with long pubescence. (18) Foreleg: tarsi with hairs pale yellowish-brown, basitarsus parallel sided, about 4X as long as width, hairs thick, erect and spine-like with a lateral patch of short brown erect hairs distally; tibia distally broadened, about 2.5X as long as greatest width, with brownish erect hairs, longest ventrally; femur about 3X as long as greatest width, with branched dark sparse hairs ventrally, nearly bare dorsally; trochanter slender, about 2X as long as distal width, with hairs erect; coxa subtriangular, slightly depressed laterally, with branched dark brown hairs. (19) Middle leg: as foreleg, except as follows: basitarsus without lateral patch of short hairs distally; tibia with apicoventral patch of dark, long and dense pubescence on apical 2/3; femur with a lateral patch of dense short golden hairs proximally, and a patch of black long hairs near proximal margin; trochanter distally broadened, length 1.5X width; coxa somewhat hidden within ventral pleuron; tibial spurs translucent yellow, apically darkened; inner hind tibial spur microserrate, with over 15 short, close teeth; outer hind tibial spur weakly curved at apical 1/3. (20) Hind leg: as middle leg, except as follows: basitarsus 3.5X as long as greatest width with several branched hairs, pubescence less dense than on tibia; tibia slender, 4X as long as greatest width, densely pubescent, hairs brown-black, long and erect; femur 4X as long as greatest width, without lateral patch of hairs, scopa well developed, with long mixed dark and pale branching hairs, somewhat sparse; trochanter and coxa with long, branching, dark brown pubescence; trochanter much shorter, nearly as long as wide; coxa similar to that of foreleg. Metasoma: (21) Terga: T1 shiny brown with a medial yellow band, apical margin hyaline, minutely punctate; T2– T5 dull and brown without metallic reflections; pubescence pale, long and branched on T1, short and pale on T2– T4, long and dark on apical T5, sparse long hairs about 3X as long as short erect hairs. (22) Sterna: S1 with white long pubescence basally; S2–S5 with hairs long and black, S2–S4 with shorter pale hairs along apical margin, S5 with long whitish hairs along apical margin; S6 with dense whitish hairs covering surface.

Male: unknown.

Material examined. GUATEMALA, Quiche, 2kms S Chichicastenango Rio Tesoro , 11 September 1987, M. Sharkey (holotype female [ CNC]) .

Etymology. This species is named in honour of Cory Sheffield who has supplied the single specimen of this species, and who has been of great assistance throughout this study.

Figures

FIGURES 180–181. Mexalictus sheffieldi Dumesh, n. sp., 180. Female lateral habitus, 181. Female head. Scale bars = 1mm.