Xestipyge multistriatum (Lewis)

Warner, William B., 2021, A brief review of the New World Xestipyge Marseul (Coleoptera: Histeridae: Dendrophilinae: Paromalini) with description of a new species from the southwestern USA, Insecta Mundi 2021 (854), pp. 1-12 : 7-8

Xestipyge multistriatum (Lewis)

Figures 8–9 , 16

Carcinops (Xestipyge) multistriata Lewis 1888: 209 . Type locality: Mexico: Guanajuato, Mexico City, Atlisco.

Xestipyge multistriatum: Lewis 1905: 37 .

Diagnosis. Head with scattered moderate punctures on vertex at each side, punctures (other than ground punctures) lacking along midline and on clypeus; pronotum with scattered moderate punctures in about lateral thirds and in narrow band about 3 punctures deep in medial quarter along posterior margin reduced to single line at each side before lateral dense area, leaving trapezoidal middle portion subimpunctate. Elytron with epipleuron wide, outer subhumeral stria complete in middle third or more, “crowded by” and more or less merging with epipleural stria, inner subhumeral complete to base, dorsal striae complete except for 5th reaching nearly basal quarter beneath sutural arch, dorsals with strial punctures variable in density, mostly separated by about 1 to 3 times their own diameters, but with some stretches without punctures (especially on sutural and striae 1–3), punctures distinctly crenulating strial channels of 4th, 5th and sutural arch, much less so on dorsal striae 1–3; dorsal intervals 1–5 with 2 pseudostriae that are somewhat shorter, narrower and less deeply impressed than dorsal striae, in intervals 1–2 outer pseudostriae nearly reaching base, inner striae of all dorsal intervals and outer pseudostriae of intervals 3–5 extending from apex to about basal third or half, variably tending to break up into puncture lines in their basal portions, sutural interval with 1 pseudostria disappearing in basal half. Pygidium apically submarginally rather broadly sulcate, sulcus narrowly interrupted at midpoint. Tegmen with basal piece about as long as parameres; parameres rather narrowly (i.e., in about apical fourth) triangularly expanded to about apical tenth, widest width about 1/3 length ( Fig. 16 ).

Length: 2.1–2.5 mm; total length: 2.7–3.0 mm; widest width: 1.7–1.9 mm (3 specimens measured).

Range. Mexico. Lewis (1888) mentions localities in the states of Guanajuato, D.F., and Puebla. Additionally, I have examined specimens from the Mexican states of Sonora and Veracruz. Also, see “remarks” section below.

Habits. Label data indicate this species has been collected in association with Atta species ant refuse piles, primarily those of Atta mexicana (Smith) , and occasionally at lights.

Remarks. This species is likely to be confused only with X. garbigliettii ; however, that species has the elytral pseudostriae broken into sinuate segments rather than being straight and mostly complete. The male tegmen is also very different, with the parameres thicker and more strongly and more apically triangularly expanded; in males of X. garbigliettii the parameres are more delicate, with the subapical expansion more gradual and less apical. I have seen a few Central American specimens collected from Atta nests that are slightly smaller and less distinctly sculptured than the Mexican specimen figured here; those specimens may represent an undescribed but closely related species.

Figures

Figures 8–9. Xestipyge multistriatum, Veracruz, Mexico. 8) Dorsal habitus. 9) Close-up of elytral sculpture.

Figures 15–19. Xestipyge species tegmena, dorsal view. 15) X. garbigliettii, Durango, Mexico. 16) X. multistriatum, Veracruz, Mexico. 17) X. conjunctum, SC, USA. 18) X. skelleyi, holotype. 19) X. geminatum, NC, USA.