Sphaeropthalma megagnathos Schuster, 1958

Boehme, Nicole F., Tanner, David A., Williams, Kevin A. & Pitts, James P., 2012, Faunal study of velvet ants (Hymenoptera: Mutillidae) and their activity patterns and habitat preference at Ash Meadows National Wildlife Refuge, Nye County, Nevada, USA, Zootaxa 3587, pp. 1-45 : 31-33

Sphaeropthalma megagnathos Schuster, 1958

Sphaeropthalma (Photopsis) megagnathos megagnathos Schuster, 1958: 36 ,

3. Holotype: Arizona, Ehrenberg (UMSP).

Sphaeropthalma (Photopsis) megagnathos aurifera Schuster, 1958: 36 ,

3. Holotype: Arizona, Tinajas Atlas Mountains (UMSP).

Diagnosis. MALE. The male of S. megagnathos can be separated easily from all other nocturnal species by mandibular morphology: the mandibles are very broadly dilated, especially ventral portion apically, distally much wider than width at ventral angulation, the ventral basal tooth of the mandible is small, and the apex is vertical (see Pitts 2006: Fig. 7 ). Also, the head is long and parallel posteriorly, the clypeus is deeply depressed below the dorsal mandibular margin, the mesosternum lacks tubercles, the wings are yellowish-hyaline, and the sternal felt line is absent. The genitalic morphology also is diagnostic (see Pitts 2006: Figs 17–19). In some specimens the coloration of the integument and setae are bright orange, while in others the setal coloration varies from orange to white and the integument is stramineous to castaneous. FEMALE. The female of this species is easily recognized by weak to non-existent ventral angulation located basally on the mandible while the mandible lacks an elongate tooth at the termination of the dorsal carina, distinctly petiolate metasomal segment 1, the granulate pygidium, presence of plumose setae especially on the fringes of the metasomal tergites, the sparse long orange setae that does not obscure the integumental sculpturing and the anterior raised areas just lateral of the midline on the second tergum that has tuberculate sculpturing.

Description of female (hitherto unknown). Coloration and setal pattern. Integument ferruginous, except segments 3-6 infuscated, and antenna and legs orange. Femur of hind leg sometimes infuscated. Pronotum, pleura, propodeum, and metasoma except T2 medially with sparse, erect, white to dirty yellow brachyplumose setae not obscuring integumental sculpture. Dorsum of mesosoma and T2 medially with sparse, erect reddish orange brachyplumose setae not obscuring integumental sculpture. Posterior margin of head, pronotum, pleura, and T1 with short white plumose setae. Fringes of metasomal terga and sterna with dense white plumose setae.

Head. Rounded posteriorly, not as wide as mesosoma; coarsely punctate. Eyes round. Antennal tubercles slightly granulate. Scrobe with lateral carina beginning just below eye, becoming weaker above height of antennal tubercle but continuing to antennal tubercle. Mandible bidentate, with slight ventral angulation basally; dorsal carina continuing to internal tooth. Genal carina absent. Flagellomere 1 ~2.0 × pedicel length; flagellomere 2 ~1.5 × length of pedicel. Clypeus truncate with slight median emargination; tuberculate posteriorly, appearing longitudinally carinate from anterior margin to posterior tubercle.

Mesosoma. As wide as long. Humeral angles dentate. Dorsum with distinct lateral margin. Coarsely punctate. Propleuron coarsely to moderately punctate. Mesopleuron with medial area moderately punctate and produced outward from dorsal to ventral margin; otherwise glabrous and nitid. Metapleuron and lateral faces of propodeum glabrous and nitid. Propodeum with distinct vertical and dorsal faces; reticulate.

Metasoma. Segment 1 distinctly petiolate with segment 2. T1 moderately punctate. T2 coarsely confluently punctate. T2 with anterior raised ovate areas located just lateral of midline with conspicuous raised puncture margins; area with tuberculate sculpture. T3-T5 and S3-S5 micropunctate, appearing granulate. S2 similar in punctation to T2, with anterior medial tumid region. Pygidium laterally defined by carinae, granulate.

Material examined. Type material. Holotypes: S. megagnathos megagnathos : Arizona, Ehrenberg, 27 April 1939, F.H. Parker ( UMSP) ; S. megagnathos aurifera : Arizona, Tinajas Atlas Mountains, 1905, W.J. McGee ( UMSP) . Other material. Nevada, Nye Co., AMNWR: Non-dune site 2: 1 ♂, LT, 26–28.V.2009, NFB ; Non-dune site 3: 1 ♂, LT, 12–14.V.2009, 2 ♂, LT, 26–28.V.2009, NFB ; Non-dune site 4: 6 ♂, LT, 26–28.V.2009, NFB, 2 ♂, LT, 8–15.VI.2009, NFB & DAT ; Sand dune site 1: 1 ♂, LT, 26–28.V.2009, NFB ; Sand dune site 2: 2 ♂, LT, 29.V.2008, NFB & DAT ; Sand dune site 4: 2 ♀, PT, 24.VI.2008, NFB, DAT & JPP, 3 ♀, PT, 8. VII.2008, 3 ♀, PT, 22.VII.2008, NFB & DAT, 1 ♀, PT, 5. VIII.2008, 1 ♀, PT, 16.IV.2009, NFB, 1 ♀, PT, 10.VI.2009, NFB & DAT, 1 ♂, LT, 21–23.VII.2009, NFB ; Sand dune site 5: 1 ♂, LT, 24.VI.2008, NFB, DAT & JPP ; Non-dune site 5: 1 ♀, PT, 24.VI.2008, NFB, DAT & JPP, 2 ♀, PT, 8. VII.2008, 1 ♀, PT, 22.VII.2008, NFB & DAT, 2 ♀, PT, 2 ♂, LT 12–14.V.2009, 1 ♂, LT, 23–25.VI.2009, NFB ; Copeland site: 5 ♂, LT, 14. V.2008, 1 ♂, LT, 30.V.2008, NFB & DAT, 2 ♀, PT, 24.VI.2008, NFB, DAT & JPP, 1 ♀, PT, 8.VII.2008, NFB & DAT, 1 ♀, PT, 5.VIII.2008, NFB, 1 ♀, PT, 17–18.X.2008, NFB & SDB ; Spring meadows site: 1 ♀, PT, 24.VI.2008, NFB, DAT & JPP ; Mesquite site 1: 3 ♀, PT, 2.IX.2008, NFB, 2 ♀, PT, 17–18.X.2008, NFB & SDB ; Wash site: 42 ♂, LT, 30.V.2008, NFB & DAT.

Distribution. USA (Arizona, California and Nevada).

Activity. Males were active in late spring (May through June). Females were found from spring through midautumn (late June through October in 2008 and April through June in 2009).

Remarks. Sphaeropthalma megagnathos were distributed uniformly over sand dune and non-dune habitats (U=20.5, p>0.1). Twenty-eight female and sixty-eight male S. megagnathos were collected throughout the course of this study. The females were collected from April through October in pitfall traps, and the males were collected from May through July. Sphaeropthalma megagnathos was not found at the NTS.

Sphaeropthalma megagnathos is a member of the S. imperialis sp.-group, which is made up of four species, S. imperialis , S. edwardsii , S. marpesia , and S. megagnathos ( Pitts 2006) . Besides S. megagnathos , all other species in the S. imperialis sp. -group have associated females. The morphology of this female is similar to the other three species in this group and can, thus, be associated with the only male lacking an associated female, S. megagnathos . A key is provided here for females of the S. imperialis sp.-group.

Figures

FIGURES 2 – 11. Male genitalia. 2. Odontophotopsis acmaea: dorsal view (left) and internal view (right); 3. O. armata: dorsal view and lateral view of cuspis (inset); 4. O. bellona: dorsal view; 5. O. mamata: dorsal view and lateral view of cuspis (inset); 6. O. microdonta: dorsal view (right) and ventral view (left); 7. O. piute: dorsal view; 8. O. serca: dorsal view and lateral view of cuspis (inset); 9. Sphaeropthalma nana: internal view; 10. S. orestes: dorsal view (left) and ventral view (right); and 11. S. parkeri: dorsal view (left) and ventral view (right).