Achradocera barbata ( Loew, 1861 )

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 : 316-320

Achradocera barbata ( Loew, 1861)

( Figs 1A–C , 9 , 10 , 26 )

Synarthus barbatus Loew, 1861: 138 .

Type-locality: “Middle States” of USA. Transferred to Chrysotus by Aldrich, 1902: 90. Holotype male, MCZ .

Chrysotus validus Loew, 1861: 68 (described from a female). Type-locality: both described from “Middle States” of USA. Synonymized with Chrysotus barbatus by Aldrich, 1902: 90. Holotype female, MCZ.

Xiphandrium americanum Wheeler, 1896: 154 . Type-locality: USA: Wisconsin, Milwaukee; Illinois, Chicago; Indiana, Whiting. Synonymized with Chrysotus barbatus by Wheeler, 1899: 37. Syntypes male and female, AMNH.

Diagnosis (male). Postpedicel longer than arista-like stylus; lower postcranial 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 broad apically, bearing ventral row of distinct setae; It 2 as long as It 3, bulged and squared; mid and hind legs simple. Hypopygium large; surstylus subrectangular, bearing 1 strong apicoventral bristle; apex folded up, with thumb-like bulged seta, rounded by small setulae basally; postgonite reduced, with anterior side fissured and bearing some small setula.

Redescription. Similar to A. angustifacies stat. rev., except as noted. Male. Body length: 2.5–2.7 mm. Wing: 2.2–2.4 mm long, 0.7–0.8 mm wide. Antenna. Postpedicel ( Fig. 9 , C) longer than arista-like stylus (MSSC); FAr ratio, 2.6. Thorax. 6–8 ac, and 5 dc pairs of setae. Wing. CuAx: 0.6; RMx: 1.65. Leg I. 35, 30, 15, 4, 5, 4, 4. Tarsomere 1 slightly broad apically, bearing ventral row of distinct setae (MSSC); t 2 about same length as t 3, bulged and squared (MSSC). Leg II. 40, 45, 20, 8, 5, 4, 3. F brown infuscated dorsally, but infuscation weaker than FI; T with anterior seta at basal 1/4 and 4 setae at apex (1 ad, 1 pd, 1 av and 1 pv). Leg III. 38, 42, 13, 9, 5, 4, 3. F with metallic green reflections; T bearing 3 pd at basal 2/3, 2 ad on basal half and 4 apical setae (1 v, 1 d, 1 ad and 1 av). Abdomen. Longer than head plus thorax length; sternite 5 with distinct setae posteriorly. Hypopygium ( Fig. 10A–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 mid-length; surstylus subrectangular, bearing 1 strong apicoventral seta; apex folded up, with thumb-like expanded 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 to basiphallus; ejaculatory apodeme digitiform, long and straight.

Female. Similar to males, except by MSSC and as noted. Body length: 2.6–2.67 mm. Wing: 2.7–2.76 mm long, 0.98–1.04 mm wide. Terminalia. As in generic description (similar to Fig. 24 ).

Distribution. Eastern Canada and eastern USA ( Fig. 26 ).

Material examined. Canada. Ontario. 1♂, “ Rondeau Pk , ON | 2–13.vii.1985 | L. LeSage & | A. Wooliffe”; “Int. Trap 2 | in maple- | beech for.”; “ Achradocera | barbata (Loew) | Det. S.E. Brooks, 2024”; USA. Alabama . 1♂, 1♀, “W FK Anderson Crk | 1/ 3 mi S Grassy | Lauderdale Co AL Z 7-VIII-92 | R. Hurley”. Delaware . 1♂, “ DELAWARE: New Castle Co. | Brandywine Creek | Rockland 160’ | 9-IX-2007, J.B. Runyon ” ; 1♂, “ Rehoboth DEL | 25 June 1959 | A. L. Melander ”, “ALMelander | Collection | 1961”. Florida . 1♂, 1♀, “FL: Hendry Co. | Lake Harbor, John | Stretch PK 22 XII 2002 | R. L. Hurley & J.B. Runyon colrs.” ; 4♂, “ Holly Hill | 14 Fb 42 Fla | ALMelander”, “ALMelander | Collection | 1961” ; 4♂, “ R. PalmPark | 1 Fb. 38 Fla | ALMelander”, “ALMelander | Collection | 1961” ; 1♂, “ SilverSprng | 12 Mar 42 Fla | ALMelander”, “ALMelander | Collection | 1961” ; 1♂, 2♀, “ FLORIDA, Highlands Co. | Lake Placid | 4 May 1986 | W. E. Steiner ” ; 2♀, “ FLORIDA, Lake Co. | 11 km. E Altoona | Clearwater Lake | 6 May 1986 | W. E. Steiner ”. Georgia . 1♂, 1♀, “ 1 mi S Norristown | Treutlen Co GA | 2-VIII-88 | R. Hurley”. Illinois . 2♀, “ Big Rock Creek | 5 mi WNW Kaneville | Kane Co. IL | 11-VIII-91 | R. Hurley” ; 5♂, “ River Forest | 16/7/35 ILL | A. L. Melander ”, “ALMelander | Collection | 1961”. Indiana . 1♂, 1♀, “ West Beach Z Indiana Dunes Na. Lksh | Porter Co. IN | 11-VIII-91 | R. Hurley”. Iowa . 1♂, 1♀, “ Wapsipinicon R . | 3 mi NNE Dunkerton | Black Hawk Co. IA | 15-VII-91 | R . Hurley . Kentucky. 1♂, “ KENTUCKY: Madison Co. | Berea College Forest | Cowbell Creek Area | 37.5445ºN 84.2289ºW | 22–29.vii.2013, Malaise | Chapman & Stedenfeld” ; 1♂, “ KENTUCKY: Pike Co. Russel Fork River , 850ꞌ | 2 mi. SE of Elkhorn City | N37º17.891′; W82º19.414′ | 3-VII-2006; J. B. Runyon ”. Louisiana . 6♂, “AveryIslLA | 19 Mar ‘42 | ALMelander”, “ALMelander | Collection | 1961” ; 1♂, “LakeProvLa | 14July1953 | W W Wirth” ; 4♂, “ Opelousas | May 1897 [2 labels with April ‘97] | Pilate L A”, “ALMelander | Collection | 1961”. Maryland . 2♂, “ Prince George | Co Md | VII-4-54 | OWSabrosky”. Missouri . 4 ♂, “ Little Otter Crk | 1 mi E Hamilton | Caldwell Co MO | 14-VII-89 | R. Hurley”. New York . 3♂, 2♀, “ 3.5 mi NW Coeymans Hol | Albany Co. NY | 23-VII-91 | R. Hurley”. North Carolina . 1♂, “ NORTH CAROLINA: | Columbus Co. | Lake Waccamaw | 25 May 1984 ”, “ W. Steiner, D. Bogar, A. Gerberich, J. Boyd collectors”. Ohio . 1♀, “ 2 mi N Dumontville | Fairfield Co OH | 2-VIII-92 | R. Hurley”. Oklahoma . 2♀, “. 5 mi W Vinita | CraigCo OK | 19-VII-93 | R. Hurley”. Pennsylvania . 1♂, “ PENNSYLVANIA: Centre Co. | Spring Creek, 4 mi. SW of | Bellefonte ( Benner Springs ) | N40º51.688′; W77º48.598′ | 23-V-2007; J. B. Runyon ” ; 1♂, “ PENNSYLVANIA: Centre Co. | Poe Paddy SP, Penns Crk | 4-VIII-2007, J. B. Runyon ” ; 1♂, “ PENNSYLVANIA: Centre Co. | Sixmile Run 1700’ | 6 mi SE of Phillipsburg | N40º49.612′; W78º06.844′ | 29-VII-2006; J. B. Runyon ” ; 1♂, “ PENNSYLVANIA: Centre Co. | Big Hollow, 1 mi N of | University Park , 1300’ | N40º49.612′; W77º51.719′ | 1-VIII-2006; J. B. Runyon ” ; 1♂, “ PENNSYLVANIA: Centre Co. | Colyer Lake; 8 mi. Se of | State College , 18- V-2005 | J. B. Runyon ” ; 2♂, “ PENNSYLVANIA: Centre Co. | Millbrook Marsh 775’ | 1 mi. E. of State College | 15-V-2005; J. B. Runyon ” ; 1♂, “ PENNSYLVANIA: Fulton Co. | Little Tonoloway Creek | 2 mi. E. Amaranth 700’ | N39º47.936′; W78º14.489′ | 6-VII-2006; J. B. Runyon ” ; 1♂, “ PENNSYLVANIA: Mifflin Co. | Reeds Gap State Park | Honey Creek | 18-VIII-2007, J. B. Runyon ” ; 1♂, “ PENNSYLVANIA: Huntingdon | Co., Perez Lake , 800’ | 14-V-2004, J. B. Runyon ”. South Carolina . 1♂, “ SOUTH CAROLINA: Pickens Co. | Easley, Middle Branch | of Big Brushy Creek , 950’ | N34º47.724′; W82º33.201′ | 30-VI-2006; J. B. Runyon ” ; 1♂, “ SOUTH CAROLINA: Beaufort Co. | Fripp Island ”, “ 26.IX.1973 | G. C. Steyskal ”. Texas . 1♂, 1♀, “ Neches R. @ Rose City | Orange Co. Tx. | 15-VIII-81 | R. Hurley”. Virginia . 1♂, “ Virginia: Augusta Co. | Lewis Creek | 2 mi. E of Staunton | 21-VII-2007; J. B. Runyon ” ; 1♀, “ Virginia: Dickenson Co. | Pound R. Rec. Area | 11-May-2000 | J. B. Runyon colr.” [ MZUSP] ; 2♂, 3♀, “ Virginia: Dickenson Co. | Cranes Nest Rec. Area | 18-May-2000 | J. B. Runyon ” [1♀ housed in MZUSP] ; 1♂, “ Virginia: Dickenson Co. | Cranesnest River , 1250’ | 2.5 mi. E of Clintwood | N37º09.157′; W82º24.628′ | 29-VI-2006; J. B. Runyon ” [ MZUSP] ; 1♂, “ Virginia: Dickenson Co. | Cranesnest R., 1250’ | 2 mi. E. of Clintwood | 24-VI-2005, J. B. Runyon ” [ MZUSP] ; 1♂, “ Virginia: Dickenson Co. | McClure River | 3 mi. S Clinchco 1270ꞌ | 8-V-2004, J. B. Runyon ”, “ Achradocera barbata (Loew) | det. J. B. Runyon 2016” [handwritten] .

Wisconsin. 1♂, “PotatoLake | 9/7/33 WISC | ALMelander”, “ALMelander | Collection | 1961”. [Most specimens housed in USNM, except specimens collected by J. Runyon and/or R. Hurley, housed in MTEC and the Canadian specimen, housed in CNC] .

Remarks. Previously, A. barbata was traditionally considered as a species with a broad range distribution in the New World, reaching Tonga French Polynesia (likely dispersed to Hawaii by accidental human introduction; see Bickel 2000). Despite the historic misleads regarding the taxonomy of A. barbata, Runyon (2020) clarified its identity, and the species was straightforward recognized by the features mentioned in the comparative diagnoses of the species. After an extensive survey, the distribution range of A. barbata is now well-defined and restricted to eastern North America.

Figures

FIGURE 1. SEM of the synapomorphies of Achradocera. Achradocera barbata: A. Postgena of head showing ventral flattened postocular setae. B. lateral view of postpedicel. C. Setae of postpedicel and insertion of subapical arista [broken] indicated by red arrow. Achradocera apicalis: D. Head, frontal view.

FIGURE 9. Achradocera barbata. A. Habitus, left lateral. B. Thorax, dorsal. C. Head, frontal. D. Leg I, showing It1-2. Scale bar: A, 1 mm; B–D, 0.2 mm.

FIGURE 10. Achradocera barbata, 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.