Mexalictus (Georgealictus) veracruzense 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 : 74-75

Mexalictus (Georgealictus) veracruzense Dumesh , new species

( Figs. 182–183 )

Holotype. Female. MEXICO, Veracruz, Hwy 125 Hualusco to Fortin de las Flores BN, Danforth & Minckley, 2 Jan 1989 [ KUM].

Diagnosis. This species can be distinguished from others by the following combination: head and mesosoma metallic green; basal striation of metapostnotum absent. It is similar to M. crypticus but can be separated mainly by the absence of striation on the metapostnotum.

Description. Female (Holotype): Body length 8.8mm, wing length 7.0– 7.1mm, head width 2.0mm, ITW 1.43–1.45mm. Head: round, L:W = 1:1. (1) Labrum and mandible: labrum with subrectangular basal area, basal elevation sulcate, with a medial depression, narrow triangular distal process; mandible basally black, becoming red in apical 2/5. (2) Clypeus: brassy in basal 1/2, becoming shiny black apically; length 0.8X length of supraclypeal area, 3/4 of length below lower ocular tangent, weakly convex in lateral view, slightly less protuberant than supraclypeal area; punctures dense laterally and basally, separated by less than <1pd, somewhat interrupted medially, punctures becoming sparse, larger, and coarser apically. (3) Supraclypeal area: mostly dull except basal shiny area around antennal sockets; convex, slightly more protuberant than clypeus; apical width subequal to length; punctation slightly denser laterally, punctures separated by 1pd, becoming sparser medially. (4) Lower paraocular area: mostly dull becoming shiny towards paraocular lobe; punctation becoming less crowded below antennae, especially towards supraclypeal area (2pd); paraocular lobe shiny and impunctate. (5) Frontal area: frontal line carinate only between antennae, from basal third of supraclypeal area to upper antennal margins, with a visible shiny line reaching median ocellus; punctures dense and crowded; compound eye more convex below than above. (6) Vertexal area: shiny, with a weak transverse depression; OOD = 2.0MOD, IOD = 2.0MOD, OVD = 1.5MOD; punctures dense and crowded, separated by 0.25pd at most, coarse and crowded medially, more separated laterally. (7) Genal and hypostomal areas: genal area shiny, narrower than compound eye in lateral view; punctures separated by 1–2pd above and>3pd below, hypostomal area nearly impunctate, bare and slightly dull. (8) Antenna: scape reaching past median ocellus, pedicel slightly longer than wide, F2 shorter than F1, flagellomeres slightly increasing in length distally, F2–F5 wider than long, F6–F9 quadrate, F10 longer than wide. Mesosoma: (9) Pronotum: smooth, impunctate, shinier laterally than dorsally, nearly bare; pronotal lobe pubescent, bearing pale branched hairs. (10) Mesoscutum: mostly dull, slightly shiny laterally; granular along margins and median line; pubescence whitish with several black hairs mostly evident anteriorly; punctures separated by 1pd in central disc becoming more sparse anteriorly, separated by 2–3pd. (11) Mesoscutellum: entirely shiny, medial line slightly raised basally; punctures fine and dense around margins and medial line (1pd), well separated on central disc (>2pd). (12) Metanotum: entirely shiny below pubescence; punctures extremely fine, separated by 3–4pd. (13) Mesopleuron: dull, punctures shallow and well separated (2–3pd); pre-episternum with punctation similar to mesopleuron, punctures coarse but shallow anteriorly; hypoepimeral area and central episternum dull, with fine scattered punctures above, impunctate below; pubescence erect, with few dark hairs among light hairs. (14) Metapleuron: shiny, but somewhat granular, transversely striate basally, with black minute pubescence. (15) Metapostnotum and propodeum: metapostnotum dorsally bare and weakly granular, length 0.85X length of mesoscutellum, striation present basally, extremely short, longest laterally, obscure and nearly absent centrally; propodeum strongly sloping posteriorly, with long white hairs laterally and 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 1–1.5 vein widths basad of 2 nd transcubital vein. (17) Tegula: punctate anteriorly, dark brown, shiny posteriorly, punctate with longer, dark pubescence anteriorly. (18) Foreleg: tarsi with hairs dark reddish, basitarsus parallel sided, about 4X as long as width, hairs thick, erect and spine-like with a lateral patch of short golden erect hairs distally; tibia distally broadened, about 2.5X as long as greatest width, with dark brown-black 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 hairs, a mixture of dark and pale hairs. (19) Middle leg: as foreleg, except as follows: basitarsus without lateral patch of short hairs distally; tibia with lateral patch of pale, 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. (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 brown branching hairs, somewhat sparse; trochanter and coxa with long, branching, black pubescence; trochanter much shorter, nearly as long as wide; coxa similar to that of foreleg; tibial spurs translucent yellowish red, apically darkened; inner hind tibial spur microserrate, with over 15 close teeth; outer hind tibial spur weakly curved at apical 1/3. 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 dark on T2–T4, long and dark on 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, present on apical half of sternite, S6 with few short and erect black hairs on apex, otherwise bare.

Male: unknown.

Material examined. MEXICO, Veracruz, Hwy 125 Hualusco to Fortin de las Flores BN, Danforth & Minckley, 2 Jan 1989 (holotype female [ KUM]) .

Etymology. This species is named for its type locality in the state of Veracruz, Mexico.

Phylogenetic analysis

A total of 43 characters (Appendix) were coded for all species of Mexalictus and the outgroups. The phylogenetic analysis resulted in 4 equally most parsimonious trees (EMPTs) of 176 steps (Ci=36.4, Ri=56.6). Using successive approximations character weighting (SACW), one tree of 3504 steps was retained after two iterations (Ci=48.8, Ri=75.5). Winclada ( Nixon, 2002) was used for purposes of mapping character transformations onto the tree, while Mesquite ( Maddison and Maddison, 2011) was used to produce a simple colour coded tree ( Figs. 184 and 185 , respectively).

The resulting phylogeny ( Figs. 184 , 185 ) distinctly separates Mexalictus into two monophyletic groups. The tree obtained using SACW was identical to one of the 4 EMPTs and this tree is taken to be the preferred result. The final phylogeny supports the division of Mexalictus into two subgenera, with the larger, dull to non-metallic and generally somewhat wasp-like species in subgenus Georgealictus with 10 species and the smaller, more brilliantly metallic, Dialictus -like species in the nominotypical subgenus, which contains 16 species.

Figures

FIGURE 184. Phylogeny of 26 Mexalictus species and two outgroup taxa (names as shown below) using 43 morphological characters with character state changes mapped onto the tree (Winclada, Nixon 2002). Black circles indicate uniquely derived character states, white circles indicate changes that are homoplasious elsewhere on the tree. See text for details of analysis.

FIGURE 185. Phylogeny of Mexalictus edited with Mesquite (Maddison and Maddison, 2011) to show subgeneric separation of Mexalictus into Mexalictus (Georgealictus) (dark grey) and Mexalictus s. str. (light grey). Outgroups, Patellapis braunsella Michener and Thrincohalictus prognathus (Pérez) (black).

FIGURES 182–183. Mexalictus veracruzense Dumesh, n. sp., 182. Female lateral habitus, 183. Female head. Scale bars = 1mm.