Mexalictus (Mexalictus) ayalai 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 : 24-27

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Mexalictus (Mexalictus) ayalai Dumesh

new species

Mexalictus (Mexalictus) ayalai Dumesh , new species

( Figs. 100–105)

Holotype. Female. MEXICO, Jalisco, Tapalpa , N20.01406 W103.70969, 2463m, 06.x.10, S. Dumesh, [ UNAM]; collection code PCYU-MEX10-0272 . GoogleMaps

Diagnosis. Both sexes of this species can be distinguished by the following combination: supraclypeal area and clypeus nearly evenly punctate; mesoscutum with admedian line slightly raised at apex, mesoscutellum medially raised basally; metapostnotum with dorsal striate area depressed, striae covering basal 2/3; terga with apical depressed areas impunctate. Males can be identified by the simple mandible, bearing a subapical tooth and clypeus without medial depression. This species is most similar to M. punctatus and M. raavo , but can be differentiated by the depressed dorsal metapostnotum, the more sparsely punctate mesoscutum and mesoscutellum (densely punctate in M. punctatus ), and the convex upper supraclypeal area (flattened in M. raavo ).

Description. Female (Paratype): Body length 7.2–7.4mm, wing length 5.4–5.6mm, head width 1.7–1.75mm, ITW 1.25–1.3mm. Head metallic green, mesosoma dark brown without metallic reflections. Head: round, L:W = 1–1.04:1. (1) Labrum and mandible: labrum with subrectangular basal area, medial length about 0.5X width, basal elevation flattened, apicomedian area elevated, distal process narrow triangular; mandible dark brown basally, becoming red apically. (2) Clypeus: shiny, over third apical surface dark purple-brown, metallic green above; length subequal to length of supraclypeal area or slightly longer, 0.75 of length below lower ocular tangent, weakly convex in lateral view, less protuberant than supraclypeal area; punctures of 2 sizes, separated by close to 1pd throughout. (3) Supraclypeal area: shiny, convex, slightly protuberant, about 1.1–1.2X as wide as long, greatest width subequal to length from upper clypeal margin to lower margin of antennal sockets; punctures nearly even throughout, separated by 1–2pd, becoming somewhat sparser medioapically. (4) Lower paraocular area: shiny, becoming dull towards antennal socket; punctures separated by <1pd, becoming slightly sparser laterad of supraclypeal area, punctures fine towards paraocular lobe; paraocular lobe metallic and impunctate at apex, with minute punctures above. (5) Frontal area: frontal line carinate between antennae, reaching 3MOD below median ocellus, but line continuing up to shiny impunctate triangle anterior to median ocellus; compound eye more convex below than above; punctation coarse and crowded above antennae, becoming slightly sparser below ocelli. (6) Vertexal area: shiny, with weak transverse depression; IOD = 2.2MOD, OOD = 2.0MOD, OVD = 1.5MOD; larger punctures separated by 2pd, smaller punctures by <1pd. (7) Genal and hypostomal areas: genal area slightly narrower than compound eye in lateral view, shiny with fine punctures separated by 2pd, hypostomal area with extremely sparse punctures, separated by>4pd, apically impunctate. (8) Antenna: dark brown, scape, pedicel, and F1–F3 darker than F4–F10; scape reaching posterior margin of median ocellus, pedicel slightly longer than wide, F2 and F3 subequal, both wider than long and shorter than F1, F2 to F10 slightly increasing in length apically, F10 longer than wide. Mesosoma: (9) Pronotum: smooth, nearly impunctate, polished; posterodorsal margin of pronotum with complete band of hairs, including pronotal lobe which is densely outlined. (10) Mesoscutum: surface shiny, except dull due to microsculpture around admedian line; punctures of 2 sizes, larger punctures separated by>4pd, smaller punctures separated by 2–4pd on disc, but denser around admedian and parapsidal lines (~1pd). (11) Mesoscutellum: disc shiny, with a median raised line on basal half; large punctures similar to those of mesoscutum, small punctures finer and sparser than those on mesoscutum, separated by 3–5pd, except denser along medial line and apical margin (1–2pd). (12) Metanotum: shiny; large punctures similar to those of mesoscutum and mesoscutellum, but small punctures less distinct. (13) Mesopleuron: shiny becoming minutely dull posteriorly; punctures of 2 sizes, larger punctures separated by>4pd, smaller punctures separated by 2–5pd, denser on upper 2/ 3, becoming sparser below; pre-episternum weakly dull anteriorly, punctation slightly denser than mesopleuron; hypoepimeral area and disc of episternum smooth, shiny and very sparsely punctate. (14) Metapleuron: mostly shiny, with basal transverse striation strong on upper 1/3, impunctate below where surface is smooth but weakly imbricate. (15) Metapostnotum and propodeum: dorsal length of metapostnotum slightly less than posterior width; dorsal area bare, strongly imbricate to weakly granular basomedially where surface is slightly depressed; propodeum somewhat shiny, smooth and impunctate posteriorly, posterior margin rounded; dorsal striation on metapostnotum reduced and irregular, covering about dorsal surface. (16) Wings: clear, veins brown, stigma more than 2/3 as long as marginal cell, membrane slightly infuscate; 1 st recurrent vein meeting 2 nd submarginal cell less than 2 vein widths basad of 2 nd transcubital vein. (17) Tegula: punctate except for smooth area on middle of disc, with few long branched hairs on basal 1.3. (18) Foreleg: hairs pale golden; shorter branched erect hairs on tarsus, coxa, trochanter, and femur; dense long unbranched hairs on tibia and basitarsus. (19) Middle leg: as foreleg except as follows: hairs brownish on outer surfaces of tibia and basitarsus and on basitibial plate; tibia with lateral patch of pale, long dense pubescence on apical 2/3. (20) Hind leg: as middle leg except as follows: coxa and trochanter with long, branching, pale pubescence; femoral scopa well formed with long branching hairs; tibia densely pubescent, hairs long and erect; basitarsus with some branched hairs among erect hairs, pubescence less dense than on tibia; femur 3X as long as greatest width; tibia 4X as long as greatest width; basitarsus 3.5X as long as greatest width; tibial spurs translucent yellow, apically darkened; inner hind tibial spur translucent yellow, microserrate, with over 15 long, close teeth. Metasoma: Metallic reflections on metasomal terga absent. (21) Terga: brown becoming narrowly hyaline on apex of apical impressed areas; T2–T4 with basal of disc dull with fine punctures separated by 2–3pd, apical shiny and nearly impunctate; pubescence pale on T1–T4, T5 with some dark hairs, hair reddish to dark brown on pseudopygidial area; T1 smooth and shiny, long branching pubescence present laterally, hairs longer apically on premarginal areas of T2–T4, T5 with dense pubescence, branched hairs longer than unbranched. (22) Sterna: hairs long, plumose and pale, brownish anteriorly on S5–S6, long pubescence on S1 basally.

Male (Allotype): Body length 5.9–6.1mm, wing length 4.8–5.0mm, head width 1.50–1.65mm, ITW 1.13– 1.18mm. As for female except as follows: Head: round, L:W = 0.98–1:1. (1) Labrum and mandible: labrum medially depressed, appearing slightly bilobed, with smooth elevated basal area; distal process extending beyond basal area for 0.5X length of labrum; mandible reddish, slender, with a distinct subapical tooth. (2) Clypeus: apical 1/6 non metallic brown; subapical row of dark bristles absent; punctures of one size, evenly distributed throughout (1–2pd). (3) Supraclypeal area: entirely shiny, quadrate; punctures evenly distributed, separated by 2–3pd. (5) Frontal area: frontal line not carinate above antennal sockets; (6) Vertexal area: IOD = 1.6MOD, OOD = 1.4MOD, OVD = 1.0 MOD; punctures separated by 1–2pd, becoming finer and sparser towards ocelli. (7) Genal and hypostomal areas: genal area about 0.65X compound eye in lateral view; plumose white pubescence on lower paraocular area, most obvious in lateral view, continuing to above antennal sockets. (8) Antenna: brown, reaching anterior margin of mesoscutellum; scape reaching lower tangent of median ocellus; pedicel about as long as wide; F1 about as long as wide, subequal to pedicel and F2, slightly shorter than F3–F10. Metasoma (21) Terga: metallic reflections absent; discs shiny with fine punctures separated by 4–5pd; T7 with medial longitudinal carina on basal half (sometimes obscured by overlaying T6), pydidial plate greatly narrowed apically, nearly pointed. (22) Sterna: S4 with long plumose medially directed hairs, apical margin straight; S5 slightly concave medially, medial plumose hairs longest apically, projecting medially; S6 apically rounded, bare basomedially, otherwise with short, plumose hairs medially directed. (23) Terminalia: see Figs104, 105.

Material examined. MEXICO, Jalisco, Tapalpa , N20.01406 W103.70969, 2463m, 06.x.10, S. Dumesh, (holotype female, PCYU-MEX10-0272 [ UNAM], 1 paratype female [ PCYU]); same except for: N20.01026 W103.70722, 2499m, 06.x.10, S. Dumesh, (allotype male, PCYU-MEX10-0223 [ UNAM], 4 paratype females, 7 paratype males [ PCYU],, barcode labels CCDB-09841 H04–H09); same except for GoogleMaps : Jalisco, Volcán Colima, N19.64000 W103.61742 2411m, 09.x.10 (1 paratype female [ PCYU]) GoogleMaps .

Etymology. This species is named in honour of Ricardo Ayala, the leading bee taxonomist in Mexico, and his wife Lupita Ayala, who were both part of collecting the first (and, to date, the only) series of this new species.


Universidad Nacional Autonoma de Mexico


The Packer Collection at York University