Horismenus depressus Gahan

Hansson, Christer, Aebi, Alexandre & Benrey, Betty, 2004, Horismenus species (Hymenoptera: Eulophidae) in a bruchid beetle parasitoid guild, including the description of a new species, Zootaxa 548, pp. 1-16 : 11-12

Horismenus depressus Gahan

Figs 8–13 , 22–23

Horismenus depressus Gahan, 1930:8 . Holotype female in USNM, not examined.

Diagnosis. Scutellum flat and with posteromedian part smooth and shiny ( Figs 12–13 ); female gaster short (MM/LG = 1.1) and ovate ( Fig. 8 ); female funicular segments short and stout ( Fig. 22 ), e.g. first funicular segment 2.4X as long as wide; male scape 3.7X as long as wide ( Fig. 23 ).

Description (of Mexican specimens). Length of body female 2.0– 2.1 mm, male 1.9– 2.0 mm.

Scape yellowish­white with apical 1/3 metallic bluish­green; pedicel and flagellum metallic bluish­green. Frons metallic bluish­green in female, metallic purple in male. Vertex metallic bluish­green in female, golden­green in male. Mesosoma metallic bluishgreen with purple tinges, propodeum metallic bluish­green with sunken and reticulate parts dull golden­purple. Coxae metallic bluish­green; femora, tibiae and tarsi yellowishwhite. Wings hyaline. Petiole dull golden­purple. First gastral tergite metallic bluish­green in anterior 1/3, dull golden­purple in posterior 2/3.

Antennae as in Figs 22–23 . Frons with strong small­meshed reticulation, reticulation weaker above frontal suture, interscrobal area smooth and shiny, clypeal region with weak transverse meshes; frontal suture V­shaped, terminating before reaching eyes; antennal scrobes join below frontal suture. Vertex with strong, engraved and small­meshed reticulation; with a median groove in posterior half, groove continues down on occiput. Occipital margin rounded. Ratios of HE/MS/WM female 3.6/1.0/2.2, male 3.2/1.0/2.0; POL/OOL/ POO 5.7/1.3/1.0; WH/WT 1.1.

Mesoscutum with strong large­meshed reticulation; notauli indistinct and wide in posterior 1/3. Scutellum flat, with weak and engraved reticulation, partly to predominantly smooth. Dorsellum smooth, with two large foveas anterolaterally, foveas reticulate. Coxae smooth and shiny. Fore wing speculum open below. Propodeum smooth and shiny with sunken parts reticulate; propodeal callus with 2–3 setae. Petiole 1.1X as long as wide in female, 1.4X as long as wide in male. Ratios of LW/LM/HW 1.7/1.0/1.0; PM/ST 0.8.

First tergite smooth and shiny in anterior 1/3, posterior 2/3 with micropunctures. Ratios of MM/LG female 1.1, male 1.2.

Distribution. Mexico ( De Santis 1989) and the U.S.A. (California ( Gahan 1930), Texas (Burks 1971)).

Hosts. Acanthoscelides sp. on Phaseolus spp. (new record), A. obtectus (Say) ( De Santis 1989) , “ Bruchus sp.” in Acacia seeds ( Burks 1971), Stator pruininus (Horn) from seeds of Acacia and Olneya ( Gahan 1930) . All hosts are Bruchidae (Coleoptera) . Material examined. 22 females, 21 males from Mexico ( Mexico, Michoacan, Morelos) from Acanthoscelides sp. on Phaseolus vulgaris ( CH).

Figures

FIGURES 6 – 9. Horismenus spp., gaster dorsal. 6. H. butcheri, female. 7. H. butcheri, male. 8. H. depressus, female. 9. H. depressus, male.

FIGURES 10 – 15. Horismenus spp. 10. H. depressus, head frontal, female. 11. H. depressus, head frontal, male. 12. H. depressus, thoracic dorsum, female. 13. H. depressus, thoracic dorsum, male. 14. H. missouriensis, head frontal, female. 15. H. missouriensis, head frontal, male.

FIGURES 20 – 29. Horismenus spp. 20 – 26. Antenna lateral. 20. H. butcheri, female. 21. H. butcheri, male. 22. H. depressus, female. 23. H. depressus, male. 24. H. missouriensis, female. 25. H. missouriensis, male. 26. H. productus, female. 27. H. productus, scape lateral, male. 28. H. produc­