Ceraturgus (Ceraturgus) similis Johnson

Barnes, Jeffrey K., 2008, Review of the genus Ceraturgus Wiedemann (Diptera: Asilidae) in North America north of Mexico, Zootaxa 1766, pp. 1-45 : 28-30

Ceraturgus (Ceraturgus) similis Johnson

( FIG. 8 )

Ceraturgus similis Johnson, 1912: 152 .

Type material examined. Holotype, male, UNITED STATES: “ 2 mi. above Bashbish Falls, Mass., VI.27.12”, “C. W. Johnson”, “ HOLOTYPE No. 624 (red label)”, “M. C. Z. Type 27048” (red label), “ Jan.– July 2003 MCZ Image Database”, MCZ. Bashbish Falls is located in Berkshire County, Massachusetts. Allotype, female, UNITED STATES: “Mt. Equinox, Vt, VI.5.10”, “C. W. Johnson”, “ALLOTYPE No. 625” (red label), “M. C. Z AlloType 27048 (red label)”, MCZ. Mt. Equinox is located in Bennington County, Vermont.

Additional material examined. UNITED STATES. MASSACHUSETTS. Middlesex County: Middlesex Falls, on granite ledge, 23 July 1939, Frost, Ψ, USNM.

NEW YORK. Livingston County: Portage, 22 June 1916, W. T. Davis, ɗ, USNM.

WEST VIRGINIA. Pocahontas County: 12.3 km S of Slatyfork on Rt. 150, 38°18’29”N 80°08’09”W, from blooms of Kalmia , 1 July 2001, R. Androw & K. Karns, Ψ, CMNH.

Male. Body length: 13.0– 13.4 mm.

Head. Width 1.6 times eye height. Face golden tomentose. Frons and vertex, including ocellar tubercle, shining black, except for narrow golden pollinose line above antennal bases and along inner compound eye margins. Postcranium and gena silvery to pale golden pollinose. Face with mystax of long golden setae confined to lower third; upper face with shorter golden setae almost reaching to antennal bases. Frons laterally with short, black setae. Ocellar triangle tuberculate, with about 18 long black setae. Postocular setae black, many with proclinate apices. Occiput and postgena with dense vestiture of long, slender, apically crinkled, black hair-like setae. Stipes with dense vestiture of long, slender, apically crinkled, golden hair-like setae. Proboscis black, laterally compressed, about 4.3 times as long as deep, deepest near base in lateral view, tapered to rounded apex. Palpal segments about equal in length, black, both with long, golden hair-like setae. Antenna 3.7 mm long, black, scape shining black, with black lateral setae along entire length; pedicel dull black, with black dorsolateral and ventrolateral setae at apex; flagellomeres dull black; antennomere:scape ratios 1.0:0.9:2.8:0.6:3.7.

Thorax. Cervical sclerites black, sparsely golden pollinose, with dense vestiture of long, slender apically crinkled, golden hair-like setae. Pronotum sparsely silvery pollinose, with sparse pile of long, slender, golden setae covering antepronotum and posterolateral corners of postpronotum; postpronotal lobe golden pollinose, covered with long, slender, erect golden hair-like setae. Propleuron with proepisternum silvery pollinose and proepimeron pale golden pollinose, with dense vestiture of long, declinate, golden hair-like setae on proepisternum and reclinate hair-like setae on anterior portion of proepimeron. Prosternum silvery pollinose, lacking setae. Scutum black or dark brown in ground color, silvery to golden pollinose, with bare central brown vitta extending from pronotum nearly to scutellum and pair of broad posterolateral bare patches, each divided by narrow line of pollen along transverse suture, reaching from behind postpronotal lobes almost to scutellum; lateral scutal pollen golden from postpronotal lobe to supra-alar area, otherwise pale golden or silvery; vestiture of short or long, erect or slightly reclinate setae restricted to pollinose areas surrounding vittae; anterior marginal and posterior marginal (prescutellar) setae pale, others black; postsutural setae longer than presutural setae; lateral margin of scutum, in addition to several weaker black setae, with 3 strong, pale presutural setae and 3 strong, pale postsutural, supra-alar setae. Postalar callus with short, pale hair-like setae laterally and long, strong, pale reclinate setae posteriorly. Scutellum shining black and bare at center of disc, otherwise sparsely silvery pollinose, with about 12 moderately strong, long, erect pale marginal setae, about as long as scutellum, and several marginal hair-like setae. Mediotergite shining brown, anatergite golden pollinose, katatergite silvery pollinose with fan of long, slender, apically crinkled, golden hair-like setae. Most mesopleural sclerites at least partly golden pollinose, but pollen sparse or lacking on lower anepisternum, lower katepisternum, lower and posterior anepimeron, and meron, these areas appearing shining or dull black. Posterior half of anepisternum covered with long, fine, golden, apically crinkled hair-like setae; dorsal setae declinate, ventral setae reclinate. Anterior basalare brown; posterior basalare silvery pollinose. Katepisternum with a few fine, golden hair-like setae posterodorsally. Anepimeron, katepimeron, and meron lacking setae. Basal swelling of pleural wing process golden pollinose. Subalar sclerite brown. Metepisternum and metepimeron golden pollinose; metepimeron with long, fine, apically crinkled, golden hair-like setae.

Legs. Coxae black in ground color; pale golden pollinose on anterior and lateral surfaces, black on posterior surface. Prothoracic and mesothoracic coxae densely covered with long, slender, golden, apically crinkled hair-like setae on anterior and lateral surfaces. Metathoracic coxa with similar setae anteroventrally and posterolaterally. All trochanters and femora shining black; femora covered with long golden hair-like setae, lacking long, stout setae. Tibiae shining golden brown, with dark brown apical ring; prothoracic tibia with anterodorsal and posterodorsal row of short golden setae and posteroventral row of long golden setae; mesothoracic tibia with anterodorsal, posterodorsal, anteroventral, and posteroventral rows of long golden setae; metathoracic tibia with dorsal, anterior and ventral rows of long golden setae. Tarsi shining golden brown, each tarsomere darker at apex; length of first tarsomere longer than or equal to length of second and third combined. All claws black with golden brown base. All pulvilli pale yellowish brown.

Wing. 9.9–10.3 mm long; lightly to moderately infuscated; most lightly infuscated in, and posterior to, cells br, d, and m2, more heavily infuscated apically and anteriorly; most heavily infuscated in apical portions of cells c and sc, at base of cells r1 and r2+3, and around crossvein r-m. Halter with stem and knob light brown.

Abdomen. Tergite 1 shining black in ground color; with posterior pale silvery pollinose band, narrow at midline, reaching to anterior margin laterally, with many long pale hair-like setae anterolaterally, many long pale setae posterolaterally. Tergites 2–6 shining black in ground color, with broad, posterior, golden pollinose, transverse band; bands not extending forward at lateral margin of tergite; each pollinose band with narrow anterior V-shaped notch at midline; tergite 2 with many long, slender, golden hair-like setae laterally; tergites 3–6 with shorter golden hair-like setae. Tergite 7 black. Sternites 1–7 black, covered with sparse, pale pollen and many long slender, golden, hair-like setae; setae especially heavy and dense on sternites 5–7. Terminalia black, with many long golden hair-like setae.

Female. Similar to male except as follows:

Body length: 11.3–13.5 mm.

Head. Width 1.5 times eye height. Antenna 3.9 mm long; antennomere:scape ratios (allotype specimen) 1.0:0.9:3.1:0.6:3.6.

Wing. 10.8–11.7 mm long, nearly hyaline to lightly infuscated.

Legs. All pulvilli pale yellow.

Abdomen. Tergites 2–6 with posterior pollinose bands lacking narrow anterior V-shaped notch at midline. Tergites 7–8 black. Sternites 2–6 black, covered with heavy, pale, golden pollen and many long slender, golden hair-like setae; sternite 7 black; setae especially heavy and dense on sternites 6–7.

Distribution ( FIG. 8 ). Vermont, Massachusetts, New York, and West Virginia.

Discussion. C. similis ranks among the rarest of robber flies. Only five specimens are known to exist, and they are all from the Northeast, collected early June to late July.

Figures

FIGURE 8. Distribution of Ceraturgus similis by county.