Sphaeropthalma difficilis ( Baker )

Pitts, James P., Wilson, Joseph S., Williams, Kevin A. & Boehme, Nicole F., 2009, Velvet ants (Hymenoptera: Mutillidae) of the Algodones sand dunes of California, USA, Zootaxa 2131, pp. 1-53 : 39-40

Sphaeropthalma difficilis ( Baker)

Photopsis difficilis Baker, 1905 . Invertebrata Pacifica 1: 114. Male. Holotype data: Claremont, California (CUIC). Sphaeropthalma (Micromutilla) maricopella purismella Schuster, 1958 . Ent. Amer. 37: 17. Male. Holotype data: Lost. Sphaeropthalma (Micromutilla) maricopella maricopella Schuster, 1958 . Ent. Amer. 37: 17. Male. Holotype data: Lost. Sphaeropthalma (Micromutilla) maricopella castanea Schuster, 1958 . Ent. Amer. 37: 17. Male. Holotype data: Lost. Sphaeropthalma (Micromutilla) californiense californiense Schuster, 1958 . Ent. Amer. 37: 18. Male. Holotype data:

Lost.

Sphaeropthalma (Micromutilla) californiense fuscatella Schuster, 1958 . Ent. Amer. 37: 18. Male. Holotype data: Lost. Sphaeropthalma (Micromutilla) quijotoa quijotoa Schuster, 1958 . Ent. Amer. 37: 18. Male. Holotype data: Lost. Sphaeropthalma (Micromutilla) quijotoa parrasia Schuster, 1958 . Ent. Amer. 37: 18. Male. Holotype data: Lost.

Diagnosis of male. This species is recognized by the deeply excised mandible with the tooth forming an acute angle, the lack of mesosternal processes, the marginal cell shorter than the stigma, the first segment of the metasoma petiolate with the second segment and densely punctate, the second sternite with an anteromedial tumid region, and the genitalia with a long cylindrical cuspis that is setose ventrally with the apex having longer denser setae and parameres with dense setae located medially, but internally directed, along the internal margin ( Fig. 3 ).

Diagnosis of female. The female of this species has the following combination characters: the dorsum of the body is covered with sparse erect brachyplumose setae, but the integument is not obscured, the ventral margin of the mandible has a deep excision subtended by a large rounded tooth ( Fig. 38 ), the head below eyes is parallel ( Fig. 64 ), the head evenly rounded in lateral view ( Fig. 64 ), the first metasomal segment is petiolate with the second segment ( Fig. 65 ) and the pygidium is striate to granulate.

Description of female: Coloration and Setal Pattern. Body brown to stramineous ( Figs. 64–66 ). Legs and flagellum yellow to dark yellow. Short brachyplumose setae throughout. Propodeum with plumose setae on vertical face. Tergite 1–5 with sparse fringe of white plumose setae. Legs with white brachyplumose setae.

Head. Head rounded posteriorly ( Fig. 64 ), not as wide as mesosoma, moderately punctate. Head evenly rounded in lateral view. Eye ovate, distance from posterior mandibular articulation ~ 4X visible length of pedicel. Clypeus protruding anteriorly, posteromedially produced into low triangular tubercle. Malar space parallel in frontal view. Antennal scrobe without dorsal carina. Antennal tubercle glabrous, except with carinate apical margin. Flagellomere I ~ 1X length of pedicel. Flagellomeres II–III ~ 1X length of pedicel or slightly longer. Flagellomeres II–X produced apically on ventral side; appearing crenulate. Mandible bidentate apically ( Fig. 38 ). Ventral mandibular margin with distinct round basal tooth ( Fig. 38 ). Genal carina absent. Hypostomal carinae lamellate medially.

Mesosoma. Mesosoma wider anteriorly than posteriorly, longer than broad ( Fig. 66 ). Mesosoma densely confluently punctate on dorsum. Propleuron anteriorly, mesopleuron medially running vertically, and lateral margin of propodeum with extreme ventral region punctate. Humeral angle dentate. Epaulet not prominent. Three to four transverse carinae present on dorsum of propodeum, appearing denticulate. Distinct scutellar scale absent. Mesosternum with low transverse tubercle present medially just anterior to mesocoxa. Metasternum tridentate. Propodeum with distinct dorsal and vertical faces.

Metasoma. Segment 1 indistinctly petiolate to subsessile with segment 2. T1 with small sparse punctures. T2 with dense moderate punctures anteriorly. T2 with felt line, 0.2X length of tergite. T3–5 shagreened. T6 with distinct pygidial area weakly defined laterally by carinae; surface longitudinally striate-granulate, convex. S2 with slight anteromedian tumid region. S2–5 with punctation similar to tergites.

Length. ~ 2.5–5.5 mm.

Material examined. California, Imperial Co. : Algodones Dunes: S Ruthven, 1 male, 24.Apr.2003, D. Yanega ( KAWC); 7.5 km N Glamis, 1 male, 11–15.Sep.2007, R. Kimsey, L. Kimsey, and T.J. Zavortink ( UCDC). Brawley, 9 males, 22.Jun.2004, K.A. Williams ( KAWC); 1.5 mi. SW Coachella Bridge #1 32°50’3” N 115°7’11” W, 1 female, 12.Apr.1979 ( CDFA); Glamis, 9 females, 26.May.1971, 20 females, 29.May.1971, 2 females, 24.Apr.1972, pit trap, M.S. Wasbauer ( CDFA), 1 female, 2.Jun.1971, A.J. Gilbert ( CDFA); Glamis, 3 mi. NM, 4 males, 15–16.Sep.1972, 12 females, 16.Oct.1972, Dunes at night, M.S. Wasbauer and A. Hardy ( CDFA), 1 male, 11–12.Apr.1973, black light, M.S. Wasbauer ( CDFA), 13 females, 7–12.Apr.1973, pit trap, M.S. and J.S. Wasbauer ( CDFA); Glamis, 5 mi SW, 71 males, 23.Jul.2005, K.A. Williams ( EMUS); Glamis, 6 mi. W, 1 male, 19.Sep.1966, R.A. Flock ( CDFA); Glamis, 8 mi. W, 2 males, 21.Jun.2004, K.A. Williams ( KAWC). Nevada, Pershing Co. Woolsey RR station, 2 females, 9.Sep.1974, blacklight, T.R. Haig ( CDFA). Utah, Kane Co., 3 mi. N Kanab, 1 male, 16.Jul.1975, F.G. andrews and A.R. Hardy ( CDFA).

DNA voucher specimen data. Arizona, Maricopa Co., Scottsdale , 1 male, JP146 ( EMUS); California, Imperial Co., Algodones Dunes , 5 mi SW Glamis, 1 female, 5.Aug.2005, K.A. Williams, KW15 ( EMUS).

Distribution. Found throughout most of the southwestern USA.

Remarks. The males of this species are difficult to separate from those of the following species, S. django , sp. nov. It is currently impossible to separate the females of S. difficilis and S. django , sp. nov., based on morphology alone.

The intersexual distances of this species are greater than those of the other species we are treating in this paper (Table 1). These distances are much less, however, than the interspecific differences between S. difficilis and the other Sphaeropthalma species ( Table 4 and 5). The main reason for higher genetic distances in S. difficilis is the presence of two highly variable insertions that are not present in the other species examined.

Figures

FIGURES 1 – 6. Lateral view of genitalia. 1. Acanthophotopsis falciformis; 2. Sphaeropthalma becki; 3. S. difficilis; 4. S.

FIGURES 31 – 46. Lateral view of mandible, 31 – 40 female and 41 – 46 male. 31. O. arcuata; 32. O. inconspicua; 33. O. melicausa; 34. O. obscura; 35. O. parva; 36. O. villosa; 37. Sphaeropthalma blakeii; 38. S. difficilis; 39. S. militaris; 40. S. triangularis; 41. O. ambigua; 42. O. arcuata; 43. O. aufidia; 44. O. melicausa; 45. O. becki; and 46. O. django.

FIGURES 56 – 70. Odontophotopsis arcuata, female: 56. head, anterior view; 57. lateral view; 58. dorsal view of mesosoma, anterior left; and 59. pygidium. Sphaeropthalma blakeii, female: 60. head, anterior view; 61. lateral view; 62. dorsal view of mesosoma, anterior left; and 63. pygidium. S. difficilis, female: 64. head, anterior view; 64. lateral view; and 66. dorsal view of mesosoma, anterior left. S. ecarinata, female: 67. head, anterior view; 68. head, lateral view; 69. lateral view; and 70. dorsal view of mesosoma, anterior left.