Achradocera arcuata ( Van Duzee, 1924 )

Quevedo, Lucas, Capellari, Renato S. & Lamas, Carlos José E., 2024, Taxonomic revision of Achradocera Becker (Diptera: Dolichopodidae), with description of two new species, Zootaxa 5519 (3), pp. 301-344 : 311-313

Achradocera arcuata ( Van Duzee, 1924)

( Figs 6 , 7 , 26 )

Chrysotus arcuatus Van Duzee, 1924: 48 , figs 17–18.

Type-locality: Alpine , San Diego Co., California. Holotype male, USNM .

Diagnosis (male). Postpedicel longer than arista-like stylus; lower postoccipital setae dense. Legs mostly yellow, except for FIII, dorsal surface of FI and FII, TIII at basal 1/4 and apical 1/5, and distal tarsi, which are all brown infuscated; It 1 slightly broadened apically, bearing a ventral row of distinct setae; It 2 as long as It 3, bulged and squared; leg II simple; FIII bearing a ventral protuberance at basal 1/4 bearing conspicuous setae. Hypopygium large; surstylus subrectangular, bearing 1 strong apicoventral seta; apex folded up, with a thumb-like bulged seta, surrounded by small setulae basally; postgonite reduced, with anterior side fissured and bearing some small setulae.

Redescription. Similar to A. angustifacies stat. rev., except as noted. Male. Body length: 2.7–2.8 mm. Wing: 2.4–2.5 mm long, 0.75–0.85 mm wide. Antenna. Postpedicel ( Fig. 6D ) longer than arista-like stylus (MSSC); FAr ratio, 1.18. Thorax. About 8 pairs of ac setae. Wing. CuAx: 0.65; RMx: 1.4; lower calypter yellow with fan bearing about 10 brownish setae. Leg I. 33, 27, 13, 4, 5, 3, 3. Tarsomere 1 slightly broadened apically, bearing ventral row of distinct setae (MSSC); It 2 about same length as It 3, bulged and squared (MSSC). Leg II. 28, 38, 13, 7, 4, 3, 3. T with anterior seta at basal 1/4 and 4 setae apically (1 a, 1 ad, 1 av, and 1 p). Leg III. 35, 38, 15, 9, 4, 3, 3. F with metallic green reflections, bearing ventral protuberance at basal 1/4, bearing conspicuous setae; T with 4 pd, 3 ad, and 4 apical setae (1 v, 1 d, 1 ad and 1 av) (MSSC). Abdomen. Longer than thorax length; sternite 5 bearing strong posterior setae. Hypopygium ( Fig. 7A–D ). Long, dark brown with brown cercus; epandrium circular; epandrial lobe appressed and bearing some small hair-like setae; foramen rounded; surstylus suture not evident; phallus dorsally serrate on apical half, slightly bulged at preapical mid-length; surstylus subrectangular, bearing 1 strong apicoventral seta; apex folded up, with thumb-like bulged seta, surrounded by small setulae basally and small apicodorsal seta; cercus longer than wide, with setae as figured; postgonite reduced, with anterior side fissured and bearing some small setulae, carrying two enlarged posterior arms (hypandrium apodeme) and dorsal projection connected with basiphallus; ejaculatory apodeme digitiform, long and straight.

Female. Similar to males, except by MSSC and as noted. Body length: 2.55–2.6 mm. Wing: 2.55–2.63 mm long, 0.93–0.98 mm wide. Terminalia. As in generic description ( Fig. 24 ).

Distribution. Western USA [and Hawaii, probably introduced] and Mexico ( Fig. 26 ).

Type material examined. PARATYPE 1♂, labelled: “ Alpine , Cal. | Apr. 8 ’15 | MCVanDuzee”, “Collection | J M Aldrich ”, “PARATYPE”, “ Chrysotus arcuatus V. D. [handwritten]” [ USNM] .

Additional material examined. USA. Arizona. 1♂, “ ARIZONA: Pima Co. | Cienega Creek Preserve | N32º01.09′; W110º38.58′ | 3 APRIL 2016; JB Runyon”, “ Achradocera arcuata (Van Duzee) [handwritten] | det. J. B. Runyon”; 1♂, 1♀, “ ARIZONA: Pima Co. | Tanque Verde Creek | N32º15.32′; W110º39.32′ | 03 APRIL 2011; J.Runyon”; 3♂, 4♀, “ ARIZONA: Santa Cruz Co. | Patagonia Lake | 15-IV-2003 3750’ | J. Runyon & R. Hurley”; 1♂, “ ARIZONA: Santa Cruz Co. | Pena Blanca Lake | 8 mi. NW Nogales | 14-IV-2003 3850ꞌ | J. Runyon & R. Hurley”; 1♂, “ ARIZONA: Santa Cruz Co. | Santa Cruz R / Tumacacori | N31º34.17′; W111º02.73′ | 03 APRIL 2016; J. B. Runyon”; 2♂, 1♀, “ ARIZONA: Cochise Co. | Cave Creek 5785’ | 7 mi SW Portal | Chiricahua Mtns. | 24-IV-2002 | R. Hurley & J. Runyon”; 1♂, 1♀, “Santa Maria R | 40 mi S Wikieup Yavapai Co AZ | 25-VI-82 | R. Hurley” [ MZUSP]; 3♂, “Tucson ARIZ | Sabino Gen. | 27 Apr 1948 | ALMelander”, ALMelander | Collection | 1961”; 2♂, “Tucson ARIZ | SaguaraMon | 10 Apr. 35 | ALMelander”, “ALMelander | Collection | 1961”; 2♂, “BeavrDamARIZ | 30 June 1940 | A. L. Melander”, “ALMelander | Collection | 1961”; 1♂, “Kirkland, ARIZ | Yavapai Co. | 7 Sept. 1968 | Judson May” [handwritten], “ Chrysotus arcuatus V.D. [handwritten] | d. GSteyskal’68”; 1♂, “ ARIZONA | Wickenburg | HassayampaR | 29June1953 ”, “WWWirth | Collector”; 1♂, “TempeAriz | Jn 19–21, 17”, “J M Aldrich | Collector”. California. 1♂, “ 18-XI-1985 | Lopez Cyn. | SLO Co, CA | Bourandas”, “ Chrysotus arcuatus Van Duzee [handwritten] | det. R. L. Hurley 2000”; 1♂, 1♀, “Mocho Arroyo | 19 mi SE Livermore | Alameda Co CA | 7-VII-89 | R. Hurley”; 2♂, 3♀, “Russian River @ | L. Mendocino | Mendocino Co CA | 6-VII-89 | R. Hurley”; 3♂, 1♀, “ USA: California: Monterey | Co., Arroyo Seco Cmpgrd. | 26 Apr 1998 Madeline & | Paul H. Arnaud, Jr.”; 4♂, “Redwood City, Cal. | 4-25-06 [handwritten]”, “Collection | J M Aldrich”, “ Chrysotus arcuatus V.D. [handwritten] | Det. F.C. Harmston, 1952 [label present on only one of the four pins]”; 4♂, “Clear Lake | 18/06/35 CAL | ALMelander”, “ALMelander | Collection | 1961”, “ Achradocera | det. R. Hurley ’85 [label present on only one of the four pins]”; 3♂, “OrtegaHiway | SjuanBridge | 16/7/45 CAL | ALMelander”, “ALMelander | Collection | 1961”; 8♂, “Morongo CAL | 26 Sept 44 [just one from 19/4/44] | ALMelander”, “ALMelander | Collection | 1961”; 3♂, “Mojave Desert | Thorn CALIF [one from “LoveJoySpring”] | 30 V 44. [or “10 V 44. CALIF ”] | A. L. Melander”, “ALMelander | Collection | 1961”; 1♂, 2♀, “JacumbaSprCal | June 28, 1917 ”, “J M Aldrich | Collector”; 2♂, “Green Val. | 26/7/44 CAL | ALMelander”, “ALMelander | Collection | 1961”; 2♂, “SanDiego | VIII.4.32 Cal”, “Lakeside [handwritten]”, “J M Aldrich | coll”, “ Chrysotus arcuatus Van D. | Det. F. C. Harmston, 1918”; 2♂, “PalmCanyon | 7Nov34 CAL | ALMelander”, “ALMelander | Collection | 1961”; 2♂, “Jenks Lake | 20/6/45 CAL [or “14/8/46 CAL”] | ALMelander”, “ALMelander | Collection | 1961”; 1♂, 1♀, “StanU Cal | 11 [or 12] Apr 1906 ”, “J M Aldrich | Coll”; 1♀, “Smith Riv | Rowdy Cr [handwritten] Cal”, “J M Aldrich | coll VII-11- 30 [handwritten]”; 1♂, “Stanford | Jul’15, Cal | ALMelander”, “ALMelander | Collection | 1961”; 1♀, “Alamos Creek | S. L. Obispo Co. | Calif 22 VI 45 [handwritten]”, “W. W. Wirth | Collector”, “ Chrysotus arcuatus Van D. [handwritten] | Det. F. C. Harmston, 1948”; 1♂, “CAL.: Lake | Tahoe | 10 Aug. 1960 | ALMelander”, “ALMelander | Collection | 1961”; 1♀, “Lakeside | TahoeCal”, “ JM Aldrich | Coll VI:14:27 [handwritten]”; 1♂, “Cuyamaca Prk | 6/5/45 CAL | ALMelander”, “ALMelander | Collection | 1961”; 1♂, “SEorkStAnaR | 29Jul42, CAL | ALMelander”, “ALMelander | Collection | 1961”; 1♂, “Julian CAL | 5 May 1945 |ALMelander”, “ALMelander | Collection | 1961”; 1♂, “S. Berdo MTs | Sugar Loaf 4/7/46 CAL ALMelander”, “ALMelander | Collection | 1961”; 1♂, “Temecula | 7/6/45 CAL | ALMelander”, “ALMelander | Collection | 1961”; 1♂, “Wrightwood | 24/5/45 CAL | ALMelander”, “ALMelander | Collection | 1961”; 1♂, “Pasadena, Cal. | 5/3/95 [handwritten]”, “ R. W. Doane | Collector”, “Collection | J M Aldrich”; 1♀, “ClioPlumasCoCal | July 9 1916 ”, “HG Dyar | Coll”; 1♂, “Lucia CAL | 28/7/40 | Melander”, “ALMelander | Collection | 1961”; 1♂, “UpStaAnaRiv | 30 6 49 CAL | ALMelander”, “ALMelander | Collection | 1961”; 1♂, “Lala Co. Cal. | Aug.9.11” [handwritten], “Highland shrives” [handwritten]”, “J M Aldrich | coll”; 1♂, “Three Rivers | Cal. Clbrtson”, “Collection | J M Aldrich”. Hawaii. 1♀, “ 10 mi NW Kekaha | Kauai HI | 18-VI-86 | R. Hurley”; 1♂, “ 7 mi NW Coco Palms | Keahue Str. | Kauai HI | 19-VI-86 | R. Hurley”; 1♂, “ 5 mi E Kapaa | Kauai HI | 29-VI-85 | R. Hurley”. Idaho. 1♂, 1♀, “ 4 mi. S. W. Juliaetta | Nez Perce Co., ID | 11-VIII-76 R. Hurley”; 1♂, 1♀, “ IDAHO: Blaine Co. 5025’ | Huff Creek (hot spring) | N43º21.85′; W113º47.36′ | 22-VII-2009; J.B. Runyon”; 1♂, “MoscowIda | VIII-23-12”, “J M Aldrich | coll”; 1♂, “Potlatch Ida | VI-20-07”, “J M Aldrich | coll”; 1♀, “Lewiston | Idaho ”, “J M Aldrich | coll”. Nevada. 1♂, “ NEVADA: Nye Co. | Ash Meadows NWR | Indian Garden Springs | outlet at Longstreet Rd | N36º28.05′; W116º19.58′ | 30 MAR 2018, JB Runyon”; 1♂, 2♀, “ NEVADA: Clark Co. | Red Rock Canyon NCA | Fern Canyon 4200 ft | N36º07.46′; W115º29.62′ | 25APR2014, JB Runyon”; 2♂, “ NEVADA: Elko Co. | Salmon Falls Crk | 16 mi S. Jackpot | 12 AUG2005 5400 ft | J. Runyon, R. Hurley”. New Mexico. 1♂, 1♀, “ NEW MEXICO: Catron Co. | San Francisco R. | 2 mi. S Reserve | 26-IV-2002 5800ꞌ | R. Hurley & J. Runyon”; 1♂, 1♀, “ NEW MEXICO: Catron Co. | Cottonwood Creek | 13 mi SW Reserve | 26-IV-2002 5900ꞌ | R. Hurley & J. Runyon”; 2♂, “ NEW MEXICO | Taos Co | Rio Grande | 6 July 1953 ”; 1♂, “ NEW MEXICO | Glenwood, Catron | Co. 1 June 1972 | W. W. Wirth | Malaise trap”; 1♂, “LasCruces NM | June 14, 1917 ”, “J M Aldrich | Collector”. Oregon. 3♀, “John Day R @ | 1/ 2 mi S Service Crk | Wheeler Co OR | 12-VII-92 | R. Hurley”; 1♂, “Stinkingwater Crk | 15.5 mi W Juntura | Harney Co OR (3600’) | 20-VIII-93 | R. Hurley”; 9♂, “Kerby OREG | 18 Sept 34 | ALMelander”, “ALMelander | Collection | 1961”; 1♂, “Hood R. Ore” [handwritten], “J M Aldrich | coll”; 1♂, “Corvallis Ore. | Aug.15.02” [handwritten], “J M Aldrich | coll”; 1♂, “ OREG Klamath Co | 19 mi W K Falls | VI-24-71 | George Steyskal”; 1♂, “ORE Deschutes Co | Paulina Lake | 10 July 1972 | George Steyskal”; 1♂, “ OREGON Benton Co | Finley Refuge | VII-3-72 | George Steyskal”. Texas. 1♂, “ 7 mi N Medina | Bandero Co. TX | 24-VIII-85 | R. Hurley”; 4♂, “ TEXAS, LlanoR. | Kimble Co. | 23 May 1972 | W. W. Wirth | Malaise Trap” [2♂ housed in MZUSP]; 1♂, “ TEXAS Llano Co | Enchanted Rock | 15 June 1953 ”, “W. W. Wirth | Collector”; 1♂, “ TEXAS, Aransas Co | Aransas Nat. Wlf. | Ref. 20 May 1972 | W. W. Wirth”. Utah. 1♂, “ UTAH: Washington Co. | Leeds Creek | 2-4 mi NW Leeds | 13-IV-2003 | J. Runyon & R. Hurley”; 3♂, 5♀, “ UTAH: Grand Co. | Colorado R. @ Moab | 28-IV-2001 4300ꞌ | R. Hurley & J. Runyon”. Washington. 1♂, “Uniontown | VI-26- 33 Wash”, “J M Aldrich | Coll”; 1♂, “Pullman | 9 j / 08 [handwritten] Wash”, “W M Mann | Collector”, “Webster | No 4 S50 [handwritten]”; 1♂, “Friday Harbor, Wash. | 7-17-05 [handwritten]”, “J M Aldrich | Coll”; 1♂, “Prosser | Wash | 4-V-11” [handwritten], “ALMelander | Collection | 1961”. Wyoming. 1♂, “OldFaithful | YelstPark”, “J M Aldrich | Coll VIII-11-27 [handwritten]”. Mexico. 1♂, “ Ciudad de México, Universidad Nacional Autónoma de México, Cantera Oriente, La grieta, 19.31639, -99.17179, 06.iii.2024, L. R. P. Gomes” (M. Soares, pers. comm.). [all in USNM, except specimens collected by J. Runyon and/or R. Hurley in MTEC].

Remarks. In general, A. arcuata is a readily recognizable species, primarily due to the unique modification in FIII. Its geographic distribution ( Fig. 26 ) is extensive, yet apparently well-defined. However, it is interesting to note the record for Mexico, which may suggest that A. arcuata also occurs in the Neotropics. Nonetheless, this locality is at a high altitude (approximately 2,240 m), still exhibiting Nearctic traits.

Figures

FIGURE 6. Achradocera arcuata. A. Habitus, left lateral. B. Thorax, dorsal; C. Legs, showing It 1–2, and FIII. D. Head, right lateral. Scale bar: A, 1 mm; B–D, 0.2 mm.

FIGURE 7. Achradocera arcuata, male genital structures. A. Hypopygium, left lateral. B. Hypopygium, ventral. C. Phallus, ejaculatory apodeme and postgonite, left lateral. D. Postgonite, ventral. Scale bar: 0.1 mm.

FIGURE 24. Female genital structures of Achradocera arcuata [similar to genitalia of the other species]. A. dorsal view. B. left lateral view. Abbreviation list: cerc, cercus; T8, tergite 8; T9+10, fusion between tergite 9+10; S8, sternite 8. Scale bar: 0.1 mm.

FIGURE 26. Distribution map of the genus Achradocera.